# Why not 28mm tires?



## Rogus

I realize not everybody agrees that 25mm tires are faster/better than 23mm, but IF YOU DO, then why aren't 28mm tires considered even better? Certainly there's a point where weight and aerodynamic drag becomes an issues but where is that point?


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## danl1

Rogus said:


> I realize not everybody agrees that 25mm tires are faster/better than 23mm, but IF YOU DO, then why aren't 28mm tires considered even better? Certainly there's a point where weight and aerodynamic drag becomes an issues but where is that point?


An awful lot of bikes won't take 28's, so there's that.

And honestly, saying one or the other is 'better' is right up against silly. It depends on surface conditions, rider weight, which particular tires...

but in the most general sense, I'll say 28's are near the 'too big' side of things. Unless you are rather heavy, and riding on crappy dirt and gravel roads, when they're not nearly big enough.


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## Chris-X

Rogus said:


> I realize not everybody agrees that 25mm tires are faster/better than 23mm, but IF YOU DO, then why aren't 28mm tires considered even better? Certainly there's a point where weight and aerodynamic drag becomes an issues but where is that point?


They are "better" period.

I ride a Roubaix and a kg 381 and 28's fit nicely. Only on the rear of a 381 though. The point where aerodynamics matter is when you're a pro racing for a WC. Otherwise it doesn't matter. Anyone who says it matters; their legs aren't strong enough.

The ride is so much better than 23's it's not even funny.


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## Kerry Irons

*Availability*



Rogus said:


> I realize not everybody agrees that 25mm tires are faster/better than 23mm, but IF YOU DO, then why aren't 28mm tires considered even better? Certainly there's a point where weight and aerodynamic drag becomes an issues but where is that point?


While you can argue that 28mm tires should be more common, the reality is that most high-end tires are only made up to 25mm. When the current concept of 700c clinchers replacing tubulars hit the market in the early 1980s, the tires were super narrow. They have widened considerably since so the trend may continue. That would require a lot of bike manufacturers to offer frames and forks with more clearance.


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## Chris-X

Ask Nick: Prescription lenses in the rain, Roubaix tire options, and more


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## ziscwg

You also get that light bulb effect with a lot of the 19 mm rims out there. That severe "rounding" puts extra stress on the sidewall and increases the chance of pinch flats. 

If you have some of the newer 23 mm rims, then there is less effect. However, you still have to clear your fork and rear triangle

I run 25 mm tires on 19 mm rims. That's about as much as I feel comfortable with on the light bulb effect


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## Chris-X

ziscwg said:


> You also get that light bulb effect with a lot of the 19 mm rims out there. That severe "rounding" puts extra stress on the sidewall and increases the chance of pinch flats.
> 
> If you have some of the newer 23 mm rims, then there is less effect. However, you still have to clear your fork and rear triangle
> 
> *I run 25 mm tires on 19 mm rims. That's about as much as I feel comfortable with on the light bulb effect*


Open Pro - rims - road & triathlon - Mavic

FEATURES
Maxtal
SUP
Traditional drilling
UB Control
CD
Double Eyelet
Low profile
Clincher


DIMENSIONS
ETRTO compatible size: 622 x 15
ETRTO compatible size: 571 x 15
*Recommended tyre widths: 19 to 28 mm*
Valve hole diameter: 6.5 mm
Recommended nipple length: 12 mm
Recommended rim tape: 622 x 16 x 0.6
Recommended rim tape: 571 x 18 x 0.6

As a note, people are running tyres wider than 28's on open pro's.


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## Dave Hickey

I run Panaracer Ruffy Tuffy 28c tires... 120psi max....I run them at 110psi. My favorite tire....I'm using Open Pro/Dura Ace wheels

If you don't want the extra weight for the flat protection, the Rolly Pollys are also a good tire


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## CleavesF

^^^ running 35's on mine. Not a problem


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## NJBiker72

CleavesF said:


> ^^^ running 35's on mine. Not a problem


I use old SUV tires. Passed this guy Lance on his skinny 23's. Wuss.


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## Chris-X

NJBiker72 said:


> I use old SUV tires. Passed this guy Lance on his skinny 23's. Wuss.




Lance knows there are much more important factors in one's "preparation" than tires.


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## bigbill

I like bigger tires but my custom won't take bigger than a fat 23 on the front and the Reynolds fork on my Peg won't take all 25's. My Gunnar Crosshairs with fenders that I use for commuting will fit 28's but it's tight on the front, especially if the tire picks up some mud. My MX Leader will run 28's. As far as rolling resistance and comfort, I did a ten hour double century on 25mm four seasons.


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## Chris-X

bigbill said:


> I like bigger tires but my custom won't take bigger than a fat 23 on the front and the Reynolds fork on my Peg won't take all 25's. My Gunnar Crosshairs with fenders that I use for commuting will fit 28's but it's tight on the front, especially if the tire picks up some mud. My MX Leader will run 28's. As far as rolling resistance and comfort,* I did a ten hour double century *on 25mm four seasons.


Congratulations! Very impressive!


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## 251

bigbill said:


> I like bigger tires but my custom won't take bigger than a fat 23 on the front and the Reynolds fork on my Peg won't take all 25's. My Gunnar Crosshairs with fenders that I use for commuting will fit 28's but it's tight on the front, especially if the tire picks up some mud. My MX Leader will run 28's. As far as rolling resistance and comfort, I did a ten hour double century on 25mm four seasons.


Do you have the stock Gunnar fork on that Crosshairs? I've had up to a 38mm knobby on the front of my Crosshairs and have plenty of room left for fenders:


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## bigbill

251 said:


> Do you have the stock Gunnar fork on that Crosshairs? I've had up to a 38mm knobby on the front of my Crosshairs and have plenty of room left for fenders:


I have the stock steel fork. My Gunnar is set up for road commuting so I use SKS narrow fenders which limit my clearance. At one point, I had wider fenders with more clearance, but I found that I got more splatter and crosswind issues while using 28 mm tires. The closer I keep the fender to the tire, the better.


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## Creakyknees

My racing bike won't fit 28's. My non-racing bike, I use 32's. They are just right - roll fine on pavement, can handle abuse on gravel / dirt / lite singletrack.

Before I bought the current racing bike, I was using 28's on the other bike, and racing on them. Didn't seem to slow me down too much, I won one race and had plenty of placings.


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## Pablo

dave hickey said:


> i run panaracer ruffy tuffy 28c tires... 120psi max....i run them at 110psi. My favorite tire....i'm using open pro/dura ace wheels


convert!


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## robdamanii

Chris-X said:


> Lance knows there are much more important factors in one's "preparation" than tires.


Leave it to you to throw doping into the whole mess....




The big problem I see with 28mm tires is pinch flat resistance and clearing the frame. If you can manage those well enough, knock yourself out.


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## cda 455

Rogus said:


> I realize not everybody agrees that 25mm tires are faster/better than 23mm, but IF YOU DO, then why aren't 28mm tires considered even better? Certainly there's a point where weight and aerodynamic drag becomes an issues but where is that point?


For me, the smallest tire I should run is 700x28 for speed. For comfort _and _speed for me is 700x32. For comfort in commuting, etc. 700x38+.

There's no way I would ride on 700x23 or 700x21. 700x25; Maybe.

I'm in the 200lb+ crowd (Clydesdale).


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## tarwheel2

As others mentioned, 28 mm tires won't fit on most road frames and some won't handle 25s. There isn't much selection when it comes to light weight, foldable 28s but there are some good options such as the Ruffy Tuffys, Panaracer Pasela TGs, Continental GP 4 Seasons and Clements. I tried the Paselas and didn't like them because they seemed to have a lot of rolling resistance, but I love my Conti GP 4 Seasons. Fortunately I got my 4 Seasons before the recent Conti price hikes because they are very expensive right now. The other issue to consider is weight. Most 28s seem to have wire beads and much heavier than the foldable versions.


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## Rogus

Lots of helpful information in the replies. Thanks to all.

Of course, those of you who've been around or searched already know, but I didn't realize that there were few 28mm choices in the supposedly better quality tires. I had heard that some frames wouldn't fit the larger tire, but now that I've decided I want to be able to use at least 25mm and preferably 28mm tires I will make sure to pay attention to that in my bike decision. 

@ziscwg--I had never heard of the "light bulb effect".

@robdamanii--Are you saying 28mm tires would be more susceptible to pinch flats?

@Chris-X--Thanks for the links.

@tarwheel2--Thanks for pointing out that fold-able are lighter tires than wire beaded tires. Though I'm not sure if this means there are choices of the same brand and size tire between fold-able and wired. I will have to check.


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## ziscwg

Chris-X said:


> Open Pro - rims - road & triathlon - Mavic
> 
> FEATURES
> Maxtal
> SUP
> Traditional drilling
> UB Control
> CD
> Double Eyelet
> Low profile
> Clincher
> 
> 
> DIMENSIONS
> ETRTO compatible size: 622 x 15
> ETRTO compatible size: 571 x 15
> *Recommended tyre widths: 19 to 28 mm*
> Valve hole diameter: 6.5 mm
> Recommended nipple length: 12 mm
> Recommended rim tape: 622 x 16 x 0.6
> Recommended rim tape: 571 x 18 x 0.6
> 
> As a note, people are running tyres wider than 28's on open pro's.


Sure, but 25 is MY limit I will go with. I'd love a 25 mm Road Tubeless rim right now. I would consider strapping a 23 mm RT rim on if I could find one that was 25-30 mm


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## mattotoole

Kerry Irons said:


> While you can argue that 28mm tires should be more common, the reality is that most high-end tires are only made up to 25mm. When the current concept of 700c clinchers replacing tubulars hit the market in the early 1980s, the tires were super narrow. They have widened considerably since so the trend may continue. That would require a lot of bike manufacturers to offer frames and forks with more clearance.


+1

All else being equal, a fatter tire has less rolling resistance. But all else is not equal -- 25mm is the break point for most tire manufacturers, where they don't go any larger with their best/fastest casings.

Various Continental models as well as Serfas Seca are available in 28mm, maybe bigger.

Sizes are nominal anyway. Some 25mm Michelins are more like 27mm, while some 28mm Contis are more like 25mm. 

Go as big as you can. My Klein frame will take at least a 28mm. Some frames won't take bigger than 23mm. Why people buy them is beyond me.

Note that I ride 23mm Michelin Carbons, as i've been getting them at a good price. The 25mm were a lot more the last time i bought.


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## robdamanii

Rogus said:


> Lots of helpful information in the replies. Thanks to all.
> 
> Of course, those of you who've been around or searched already know, but I didn't realize that there were few 28mm choices in the supposedly better quality tires. I had heard that some frames wouldn't fit the larger tire, but now that I've decided I want to be able to use at least 25mm and preferably 28mm tires I will make sure to pay attention to that in my bike decision.
> 
> @ziscwg--I had never heard of the "light bulb effect".
> 
> @robdamanii--Are you saying 28mm tires would be more susceptible to pinch flats?
> 
> @Chris-X--Thanks for the links.
> 
> @tarwheel2--Thanks for pointing out that fold-able are lighter tires than wire beaded tires. Though I'm not sure if this means there are choices of the same brand and size tire between fold-able and wired. I will have to check.


If the rim isn't wide enough to prevent the tire from "ballooning" it can pinch.


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## Rogus

robdamanii said:


> If the rim isn't wide enough to prevent the tire from "ballooning" it can pinch.


I think someone else called this light bulbing. :idea:

OK, so it's not solely because of it being a 28mm or larger tire, but becasue the tire width was too large for the rim. Makes sense. Is the opposite a problem? Where's the point where a tire is too narrow for a rim?


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## Chris-X

*Good Lord!*



NJBiker72 said:


> I use old SUV tires. Passed this guy* Lance* on his skinny 23's. Wuss.





Chris-X said:


> Lance knows there are much more important factors in one's "preparation" than tires.





robdamanii said:


> Leave it to you to throw *doping* into the whole mess....
> 
> 
> 
> 
> The big problem I see with 28mm tires is pinch flat resistance and clearing the frame. If you can manage those well enough, knock yourself out.


What mess are you talking about? The popular resistance to wider tyres seems to be the perceived speed losses. People seem to think they are losing 10% of their speed from tenths of a percent differences in rolling resistance. As you can see, it doesn't add up.:idea:

I didn't bring Lance up as you can see. He does know that a few tenths of a percent are nothing compared with the gains that can be made elsewhere. Do you disagree?

That's even conceding that you're losing speed by using wider tyres. I say, unless you're on the level of a pro, you're basically losing nothing. Even in crits you'll be able to corner better with wider softer tyres and aero doesn't have much of an effect unless you break away.

There is no BIG problem with pinch flats using 28c tyres on open pro's. As a matter of fact, you get fewer pinch flats. Frame clearance IS a legitimate issue. 

Smart riders will start demanding road frames that can accomodate wider tyres and smart manufacturers will provide them. 

What frame are you riding that won't allow more than 25's?


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## Chris-X

ziscwg said:


> You also get that light bulb effect with a lot of the 19 mm rims out there. That severe "rounding" puts extra stress on the sidewall and increases the chance of pinch flats.
> 
> If you have some of the newer 23 mm rims, then there is less effect. However, you still have to clear your fork and rear triangle
> 
> I run 25 mm tires on 19 mm rims. That's about as much as* I feel comfortable with on the light bulb effect*





ziscwg said:


> Sure, but 25 is *MY limit I will go with*. I'd love a 25 mm Road Tubeless rim right now. I would consider strapping a 23 mm RT rim on if I could find one that was 25-30 mm


My question; what is the source of your discomfort? Perhaps it's a misconception?


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## Chris-X

tarwheel2 said:


> As others mentioned, 28 mm tires won't fit on most road frames and some won't handle 25s. There isn't much selection when it comes to light weight, foldable 28s but there are some good options such as the Ruffy Tuffys, Panaracer Pasela TGs, Continental GP 4 Seasons and Clements. I tried the Paselas and didn't like them because they seemed to have a lot of rolling resistance, but I love my Conti GP 4 Seasons. Fortunately I got my 4 Seasons before the recent Conti price hikes because they are very expensive right now. The *other issue to consider is weight. Most 28s seem to have wire beads and much heavier than the foldable versions*.


Seriously, the weight of a wire bead compared to the weight of a kevlar bead is just a complete non issue. Stand next to your bike. Balance it and put two fingers on the bars and two fingers on the saddle and move it back and forth. It takes absolutely NO effort to do so. Do you really think you can detect the weight difference between tires.

I wouldn't argue on the ride of some tires. Currently I'm using an Armadillo 25 rear with a tire liner and I'll never use an Armadillo again. When it's new there is terrible traction while cornering, but that hasn't effected my speed in any discernable way. That's on a heavy Synergy O/C rim btw.

Really, the whole weight issue has devolved into complete silliness. When one gets into the top couple of hundred competitive cyclists in the world they can concern themselves with these trifles.

I agree that the 4 Seasons are very good..


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## robdamanii

Chris-X said:


> What mess are you talking about? The popular resistance to wider tyres seems to be the perceived speed losses. People seem to think they are losing 10% of their speed from tenths of a percent differences in rolling resistance. As you can see, it doesn't add up.:idea:
> 
> I didn't bring Lance up as you can see. He does know that a few tenths of a percent are nothing compared with the gains that can be made elsewhere. *Do you disagree?*
> 
> That's even conceding that you're losing speed by using wider tyres. I say, unless you're on the level of a pro, you're basically losing nothing. Even in crits you'll be able to corner better with wider softer tyres and aero doesn't have much of an effect unless you break away.
> 
> There is no BIG problem with pinch flats using 28c tyres on open pro's. As a matter of fact, you get fewer pinch flats. Frame clearance IS a legitimate issue.
> 
> Smart riders will start demanding road frames that can accomodate wider tyres and smart manufacturers will provide them.
> 
> What frame are you riding that won't allow more than 25's?


I disagree that you should shut your pie hole about Armstrong and his issues unless you're posting in the doping forum. We all know you're obsession knows no bounds, and most of us are sick of hearing you flap your gums about it.

Smart riders will ride what they find works for them, be it 21mm tubulars or 35mm clinchers. Your assertion that "smart" riders will demand monster tire sizes is as stupid as your harping on LA's doping.


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## Chris-X

robdamanii said:


> I disagree that you should shut your pie hole about Armstrong and his issues unless you're posting in the doping forum. We all know you're obsession knows no bounds, and most of us are sick of hearing you flap your gums about it.
> 
> Smart riders will ride what they find works for them, be it 21mm tubulars or 35mm clinchers. Your assertion that "smart" riders will demand monster tire sizes is as stupid as your harping on LA's doping.


You're the only one breaking forum rules on this thread.:thumbsup:

Grumpy asshat, no kidding!:yikes:


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## Salsa_Lover

Are we talking about touring bikes here ?


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## kbwh

Chris-X said:


> What frame are you riding that won't allow more than 25's?


Seems like my Bianchi Infinito maxes out at 25 mm. I haven't tried 28 but rear brake bridge clearance looks like not much more than 3 mm with Conti GP4season 25s.
Not that it's a problem for me. I'm 74 kg and like to run my tires at 0.5 Bar less than the Michelin recommendation for my weight.


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## Rogus

Salsa_Lover said:


> Are we talking about touring bikes here ?


I was talking about road bikes. In shopping for a new bike, I've found almost all of them in the price range I've been looking have 23mm tires except the Specialized Roubaix. Having done some research that revealed that 25mm are faster and a more comfortable ride, I wondered why we don't see more bikes coming with 25mm or even "better(?)" 28mm tires. Hence the question of why not.

It amazes me how often and how much we make assumptions about bikes and components that aren't true.


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## Salsa_Lover

Because all that "25 tires are faster" thing is BS ?

A 25 tyre would be faster than a smaller tire if it is run at the same pressure, there lies the fallacy.

First, people who run the 25s do it to have a cushier ride, so less pressure, more comfort but less performance.

Second if you run them at the same pressure as smaller tires ( let's say a 21 ) the 25 could burst before reaching the pressures a 21 can reach,

Third a road bike doesn't need more than 23. That's why they are made that way, 21 for better performance and tubulars for the best comfort/cornering/weight/speed.

If you need more, then you need a touring bike.


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## bent steel

Salsa_Lover said:


> Because all that "25 tires are faster" thing is BS ?
> 
> A 25 tyre would be faster than a smaller tire if it is run at the same pressure, there lies the fallacy.
> 
> First, people who run the 25s do it to have a cushier ride, so less pressure, more comfort but less performance.
> 
> Second if you run them at the same pressure as smaller tires ( let's say a 21 ) the 25 could burst before reaching the pressures a 21 can reach,
> 
> Third a road bike doesn't need more than 23. That's why they are made that way, 21 for better performance and tubulars for the best comfort/cornering/weight/speed.
> 
> If you need more, then you need a touring bike.


Sigh.


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## Pablo

Salsa_Lover said:


> Third a road bike doesn't need more than 23. That's why they are made that way, 21 for better performance and tubulars for the best comfort/cornering/weight/speed.
> 
> If you need more, then you need a touring bike.


Doesn't is depend on the road, I mean, don't they ride 25s and bigger on Paris-Roubaix and Flanders (I think LArs Boom even rode 30s last year)? You're definition of "road bike" seems to require only riding on smooth, paved roads.


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## robdamanii

Pablo said:


> Doesn't is depend on the road, I mean, don't they ride 25s and bigger on Paris-Roubaix and Flanders (I think LArs Boom even rode 30s last year)? You're definition of "road bike" seems to require only riding on smooth, paved roads.


For 230k? Sure. The idea that you NEED a 28mm tire to ride on anything other than smooth pavement is bull. I take 23mm tires on unpaved roads all the time to no ill effect.


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## Salsa_Lover

Pablo said:


> Doesn't is depend on the road, I mean, don't they ride 25s and bigger on Paris-Roubaix and Flanders (I think LArs Boom even rode 30s last year)? You're definition of "road bike" seems to require only riding on smooth, paved roads.


You realise you're talking about extremes don't you?

The same as guys who mention the Zoncolan every time they talk about gearing....

To ride a road bike on normal roads you don't "need" extreme things, it would be more comfortable sure but we are talking about road cycling as a sport here and not commuting or touring.


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## Pablo

Salsa_Lover said:


> You realise you're talking about extremes don't you?
> 
> The same as guys who mention the Zoncolan every time they talk about gearing....
> 
> To ride a road bike on normal roads you don't "need" extreme things, it would be more comfortable sure but we are talking about road cycling as a sport here and not commuting or touring.


I was using an example you could relate to, but it's not an "extreme" where I live, in which the majority of the county roads outside of the city limits are maintained dirt roads and, in my experience, a racing road bike, ridden for speed and not to commute or tour, is faster and performs much better with a tire larger than a 23. I could just as easily charachterise only riding on one near ideal surface as an extreme.


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## Pablo

robdamanii said:


> For 230k? Sure. The idea that you NEED a 28mm tire to ride on anything other than smooth pavement is bull. I take 23mm tires on unpaved roads all the time to no ill effect.


"Need" is an interesting concept because no one knew they "needed" 23s or pnuematic tires at all initially as they took those bikes on unpaved roads all the time to no ill effect. I've ridden 23s on godforsaken roads too, I didn't "need" bigger tires, but the bike would have performed better and gone faster with them.


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## tarwheel2

Chris-X said:


> Seriously, the weight of a wire bead compared to the weight of a kevlar bead is just a complete non issue. ..


I am no weight-weenie by any means. However, you will notice extra weight in wheels/tires much more so than the frame. If you can't tell the difference, you have either never used lighter tires or ride in an area with no hills. I had some bombproof wheels built for my commuter with 36H hubs and heavier rims than on my other bikes, but I ended up taking them off my bike because it rode so much slower. Trust me, it was the weight difference and I noticed it right away. I ride 7,000+ miles a year and notice things like this.


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## robdamanii

Pablo said:


> "Need" is an interesting concept because no one knew they "needed" 23s or pnuematic tires at all initially as they took those bikes on unpaved roads all the time to no ill effect. I've ridden 23s on godforsaken roads too, I didn't "need" bigger tires, but the bike would have performed better and gone faster with them.


I don't doubt that the bike would have felt better on larger tires, but "performed better" is really a stretch. I don't think any of us are riding on the limit of what our bikes are capable of, so I highly doubt a difference of 2mm in tire width will improve our performance noticeably.


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## Pablo

robdamanii said:


> I don't doubt that the bike would have felt better on larger tires, but "performed better" is really a stretch. I don't think any of us are riding on the limit of what our bikes are capable of, so I highly doubt a difference of 2mm in tire width will improve our performance noticeably.


Interesting, I guess from my perspective if the bike feels better to the rider, the rider can push herself and the bike more, at least to do so within her comfort zone, resulting in better overall performance. However, I see the distinction you're drawing, though I'm not sure of it's overall affect. Plus, a larger volume and lower pressue could perform better from a bike perspective on rougher surfaces, though that's a big debate as well. Your point about 2mm not being significant cuts both ways, I suppose.


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## robdamanii

Pablo said:


> Interesting, I guess from my perspective if the bike feels better to the rider, the rider can push herself and the bike more, at least to do so within her comfort zone, resulting in better overall performance. However, I see the distinction you're drawing, though I'm not sure of it's overall affect. Plus, a larger volume and lower pressue could perform better from a bike perspective on rougher surfaces, though that's a big debate as well. Your point about 2mm not being significant cuts both ways, I suppose.


The real problem is that there are so many variables involved with testing such a hypothesis (weather, rider's conditioning, wind, traffic, etc) that it would be nearly impossible to do a real world test between a 23/25/28/30mm tire and glean any meaningful data out of it.

The again, your point rings true with a lot of things: if it helps you psychologically, then it will generally help you perform better.


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## Pablo

robdamanii said:


> The real problem is that there are so many variables involved with testing such a hypothesis (weather, rider's conditioning, wind, traffic, etc) that it would be nearly impossible to do a real world test between a 23/25/28/30mm tire and glean any meaningful data out of it.


That's the brilliance of it! We don't have any pesky facts or data to get in the way of rampant speculation and hypothesization.


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## m_s

Salsa_Lover said:


> Because all that "25 tires are faster" thing is BS ?
> 
> A 25 tyre would be faster than a smaller tire if it is run at the same pressure, there lies the fallacy.
> 
> First, people who run the 25s do it to have a cushier ride, so less pressure, more comfort but less performance.
> 
> Second if you run them at the same pressure as smaller tires ( let's say a 21 ) the 25 could burst before reaching the pressures a 21 can reach,
> 
> Third a road bike doesn't need more than 23. That's why they are made that way, 21 for better performance and tubulars for the best comfort/cornering/weight/speed.
> 
> If you need more, then you need a touring bike.


My roads. Guaranteed my 35mm tires are better performers on em than your 23s. So blanket statements are kinda silly, eh?


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## Argentius

Why does everyone equate squishiness to a "better" ride?

Touring bikes should be plush.

I do not think racing bikes should be.

Note that pro racers have the options they use on Roubaix -- wider rims, 25mm tires -- available to them every day, and, bike manufacturers would be happy to give them a little more clearance if that would help.

I notice they do not make this choice. Granted, some pro racers also take the middle out of their bread and refuse to use the air conditioner.


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## Salsa_Lover

m_s said:


> My roads. Guaranteed my 35mm tires are better performers on em than your 23s. So blanket statements are kinda silly, eh?



nice touring bike.... SPD pedals and all...

why you people keep insisting citing the wrong conditions/roads/cobblestones etc. if you are riding off road, or gravel paths, or north french cobbles or wathever, that's great, I go on that on my commuter with Vittoria randoneurs 32s or on my cross bike with Grifos....

in this thread we are talking "road bikes" here, you know, roads right ?, asphalt, tarmac etc.


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## heathb

I use 25 on my racing bikes and 28 on my commuter. 

28mm tires won't fit through most forks and chainstays on road bikes, but I use a cyclocross for commuting with Mavic A319 rims, which are wider, probably 25mm wide. 

A 28 is slower if you set your bike up for them with larger stronger rims and heavier larger tubes that are necessary for 28's, but the trade off is that you'll be much more comfy with less knocks and bumps felt. 

I wouldn't want to do fast group rides with 28's, you'll notice the difference with that much mass on the outside of your wheels.


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## Will Be Was

I use Serfas Seca 28mm on my road commute bike it accommodates it. I use to by them for $16.00 now they went up $25.00. I get about 1200 miles and one flat only before I put on new pair. On my cross bike Serfas Drifter 32mm about 1100 miles on it with no flat at all.


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## Chris-X

Argentius said:


> Why does everyone equate squishiness to a "better" ride?
> 
> Touring bikes should be plush.
> 
> I do not think racing bikes should be.
> 
> Note that pro racers have the options they use on Roubaix -- wider rims, 25mm tires -- available to them every day, and, bike manufacturers would be happy to give them a little more clearance if that would help.
> 
> I notice they do not make this choice. Granted, some pro racers also take the middle out of their bread and refuse to use the air conditioner.


I could also ask, why does everyone equate stiffness with better performance?

Motorcycle manufacturers made their alloy frames less stiff for better performance.

It is well known in the transportation industry that vibrations cause fatigue. 

Tires more than any other component on a bicycle can damp vibrations.

As you've pointed out above, the superstitions and traditions of pro's may outstrip their logical thinking on the matter.

The OP is "why not 28mm tires?" IMHO, there are very few good reasons, "why not?"

Two of them were given by Kerry Irons. The rest of the reasons are, not so good.


----------



## acid_rider

I read some folks stating their 27-28mm tyres would not clear the (open) brake pads unless mostly deflated but 25-26mm width would just make it - on 100psi - with no room to spare.... 

I ride on 25mm tyres (actual width ~26-27mm in any case). My front tyre pressure is 10psi less than my rear tyre pressure. That seems to work well.


----------



## kbwh

I wonder if those folks know how to operate their brake QR.


----------



## robdamanii

kbwh said:


> I wonder if those folks know how to operate their brake QR.


Some brakes just don't open much. Ciamillos are one of the offenders in the "don't open much" category...


----------



## acid_rider

*Ultegra ?*



kbwh said:


> I wonder if those folks know how to operate their brake QR.


when I open my Ultegra (2010 model) QR brakes there is not a lot of room for a fully inflated to 7 bar (~105psi) 25mm wide tyre to get through (the actual width ~26-27mm). Of course you can always deflate tyre first but it's extra pain to do so.....


----------



## Chris-X

tarwheel2 said:


> I am no weight-weenie by any means. However, you will notice extra weight in wheels/tires much more so than the frame. If you can't tell the difference, you have either never used lighter tires or ride in an area with no hills. I had some bombproof wheels built for my commuter with 36H hubs and heavier rims than on my other bikes, but I ended up taking them off my bike because it rode so much slower. Trust me, it was the weight difference and I noticed it right away. I ride 7,000+ miles a year and notice things like this.


I don't doubt that you're noticing increased road feel but that has nothing at all to do with how fast you're riding. I was riding Veloflex Paves and could feel a grain of sand on the road. Even though Armadillo's suck, (cornering at least) I much prefer the solid feel they provide over rough roads, than feeling every single imperfection on fairly smooth roads.

Turn the cranks by hand with each one of the different weight tires you mount. That's the difference in the weight and force required and it's negligible. And believe me, I ride 10,000+ miles a year and know these small differences in weight affect comfort a great deal and speed, not so much if at all.


----------



## Jesse D Smith

Rogus said:


> I think someone else called this light bulbing. :idea:
> 
> OK, so it's not solely because of it being a 28mm or larger tire, but becasue the tire width was too large for the rim. Makes sense. Is the opposite a problem? Where's the point where a tire is too narrow for a rim?


Yes. If the tire is too narrow, it will have a shallower profile, meaning you have to run much higher pressure to avoid pinch flats. The tire will lose the roundness of its designed profile, flattening out. Cornering will be inconsistent.


----------



## ergott

My main wheels are 22-23mm tubulars on carbon hoops. My clinchers are 25mm Pro Race 3s on Hed C2 rims. The Pro Race tires measure just over 27mm on those hoops and fit in my Spooky Skeletor with Enve 2.0 fork (not much room for error).

I run 95/100psi for the tubulars and 80/85psi for the clinchers.

As far as clinchers go, they are the nicest riding wheels/tires I've used (I still prefer my tubulars). I definitely don't feel slower on them and the guys I ride with will agree when they are on my wheel. Unfortunately, this time of year is known for tearing up expensive, nice tires and I don't want to change a tubular in this cold weather. I so actually want to try next year's D2R2 ride with that setup. Should be a nice challenge.

I definitely appreciate the fact that my bike can handle that tire size. It's nice to have options.

Choose your tires for the road conditions you ride on. It's abundantly clear that different things work for different people. 

-Eric


----------



## Guest

I'm running 25s on my road bike now. I'm a lightweight rider (125lb), riding on roads littered with bumps and potholes, and consequently prefer to run low pressures (I typically run 92 PSI rear, 85 front). These are both below the _minimum_ recommended pressure on the 23s I was running before, but well within the nominal range on the 25s.

On a hill in my area I actually do notice slightly slower top speeds in roll-down coast test due to the higher rolling resistance -- though I haven't done a large enough number of trials and averages to put a definite number on the % change (wind and temperature change a lot) 

However, I am finishing rides in _faster_ overall average times than before, and ending with more relaxed arms/upper body due to the smoother ride. In my parciular case I think the 25s work better for me. Are they "faster" in the sense that they have less air drag and rolling resistance? absoltely not. 

I think this may be what the OP was saying when talking about 25s being faster. If for a paricular rider they result in a more comfortable ride, that *may* be true. In my case I doubt going to 28s or larger would be any better. I'm already able to run the pressures I want at 25s and feel no desire to drop them further. On 28s I'd be running into _maximum_ pressure limits if I kept the tire PSI the same, and would have to run heavier rims and deal with slightly higher air drag and (possibly) higher rolling resistance (it's true rolling restiance mostly comes down to pressure).



> I am no weight-weenie by any means. However, you will notice extra weight in wheels/tires much more so than the frame. If you can't tell the difference, you have either never used lighter tires or ride in an area with no hills. I had some bombproof wheels built for my commuter with 36H hubs and heavier rims than on my other bikes, but I ended up taking them off my bike because it rode so much slower. Trust me, it was the weight difference and I noticed it right away. I ride 7,000+ miles a year and notice things like this.


Rotational inertia only makes a difference during accelerations. Accelerating one gram of mass on the very surface of a tire is equivalent to accelerating two grams of ordinary mass on the bike-- because you're accelerating the wheel both linearly, and angularly, and the circumference of the wheel = the distance traveled on the road. The effect is less significant if the weight is closer to the axis of rotation (eg weight of the cassette). For steady-speed climbing only the actual weight matters. 

I agree moving from heavy to light wheels is noticeable -- rotating mass aside, a large percentage of the the weight on modern bikes is in the wheels -- but extra rotating mass shouldn't matter for climbing in particular. 

Admittedly there may be other effects from running heavier or different rims. The damping/shock absorbing characteristics like the resontant frequency of the tire+spoke+bike spring-mass systems, might change the "road feel" noticeably.


----------



## Salsa_Lover

that is actually wrong. 

your postulate says that if you are going on steady speed uphill, theoretically there is no acceleration right ?

no, that is wrong. There is an actual constant de-acceleration due to the gravitational force, that you have to overcome on every pedal stroke. 

if you stop pedaling you will deaccelerate until you start rolling downhill backwards... try it.

hence the rotational mass acceleration indeed is present and permanently. basic dynamic phyiscs here.


----------



## kbwh

I don't buy your argument, Salsa unless the rider has a very choppy pedaling style.
A normal smooth, graceful turn of the pedals will not produce changes in the angular velocity of the wheels. No resultant acceleration or deceleration, alas.


----------



## Salsa_Lover

read again kbwh

if you don't pedal you will deaccelerate fast and start going backwards ( well you will fall over first  ) 

why so ? gravitational force pushing you down and making you move backwards with increasing speed.

how you overcome this constant deacceleration ? well by constantly accelerating on the other direction.

First law of Newton.

and before you counterargument. it is not the same as on flat land, there the gravitational force doesn't push you back, it pushes you down, you have to overcome the rotational inertia at the beginning and then keep pedaling to mantain the same speed overcoming friction and wind resistance... 

Although similar it is not the same thing. if you don't pedal on flat land, you will slowly deaccelerate due to friction ( true a lot slower than on the first case ) untill you simply don't move anymore. ( and fall over  ) but you won't be pushed backwards.


----------



## kbwh

Force is not accelleration.


----------



## Salsa_Lover

no but the force is what make you accelerate.

may the force with you be

you know that in physics gravity *g* is acceleration right ?

F = mg.


----------



## kbwh

It does and it is. 
Point is that you will not have _resultant_ acceleration if the force is opposed by an equally large force.


----------



## Salsa_Lover

Sure then


the Force applied is F = m ( your weight ) . g ( gravity )

So, to overcome this force and not move down you have to generate an equal force F = m (your weight ) . *a* ( your acceleration ) ( think a trackstand uphill )

and to move upwards F = m.a1 your acceleration a1 has to be bigger than g

it is clear now ?

now think it again, the gravity acceleration g is constant. so how has to be yours ?


----------



## kbwh

I do not have to accellerate to keep my vertical speed constant (given no change in incline). Thus the angular velocity of my wheels do not change and it does not matter where the weight of my bike sits.

What happens in that nasty hairpin that suddenly gives me 20% to battle instead of 6% is another story.


----------



## Salsa_Lover

yes you have to do it, and that constantly.and you have to constantly accelerate your wheels and your bike, 

Off course this acceleration is "cancelled" by the gravity acceleration on the opposite direction so at the end you perceive no change, now you can wrongly perceive that there is no acceleration because you have constant speed. but this doesn't mean it is not there.

But well this is basic dynamic physics, one day you will understand


----------



## kbwh

I know my dynamics.


----------



## motobecane69

Salsa is correct on all accounts on this but i think a lot of you guys are getting off base. First of tall, the guy who posted the pic of the dirt road, WTF dude, your on a CX bike. As salsa mentioned, we are discussing roadbikes that are primarily being ridden on decently paved roads. I'm a 240lb clyde and I agree, there really isn't much reason to put tires bigger than a 25 on a road bike UNLESS your heavy like I am. Alas, the frame design generally doesn't allow for anythign bigger than a 25 on an aggressively setup road bike. some of the comfort geometry road bikes like Giant Defy will let you fit 28's on them, maybe even 32's. I've actually ridden on a 21mm tubulars and it's not fun and i got a blowout really easy because at my weight i've got to run the pressure so damn high that a pothole easily wrecks it. The problem is i recently switched to tubulars and I love them but they don't make many in 25mm size so options are a bit limited.


----------



## Chris-X

motobecane69 said:


> Salsa is correct on all accounts on this but i think a lot of you guys are getting off base. First of tall, the guy who posted the pic of the dirt road, WTF dude, your on a CX bike. As salsa mentioned, we are discussing roadbikes that are primarily being ridden on decently paved roads. I'm a 240lb clyde and I agree, there really isn't much reason to put tires bigger than a 25 on a road bike UNLESS your heavy like I am. Alas, the frame design generally doesn't allow for anythign bigger than a 25 on an aggressively setup road bike. some of the comfort geometry road bikes like Giant Defy will let you fit 28's on them, maybe even 32's. I've actually ridden on a 21mm tubulars and it's not fun and i got a blowout really easy because at my weight i've got to run the pressure so damn high that a pothole easily wrecks it. The problem is i recently switched to tubulars and I love them but they don't make many in 25mm size so options are a bit limited.


Why don't you run 27mm Vittoria Pave tubulars? I would and I weigh 165.


----------



## motobecane69

Chris-X said:


> Why don't you run 27mm Vittoria Pave tubulars? I would and I weigh 165.


1. They won't fit
2. I'd like to find a tire that doesn't cost $120! 

Don't get me wrong, if the ride quality is there, I'll ride them. honestly, I think i've hesitated on buying them because I hate that stupid green stripe down the middle of them that would absolutely clash with my bikes color scheme!

What sucks is my lbs gave me a pair of conti competitions FOR FREE! but they are 21mm, I blew one out the first ride on them and tire alert is fixing it now. I'm hoping I can find someone that would trade me so I can get the 25mm version of those


----------



## Chris-X

*what about*



motobecane69 said:


> 1. They won't fit
> 2. I'd like to find a tire that doesn't cost $120!
> 
> Don't get me wrong, if the ride quality is there, I'll ride them. honestly, I think i've hesitated on buying them because I hate that stupid green stripe down the middle of them that would absolutely clash with my bikes color scheme!
> 
> What sucks is my lbs gave me a pair of conti competitions FOR FREE! but they are 21mm, I blew one out the first ride on them and tire alert is fixing it now. I'm hoping I can find someone that would trade me so I can get the 25mm version of those


these

FMB PARIS ROUBAIX TUBULAR

TUBULAR TIRES


----------



## cda 455

Chris-X said:


> these
> 
> FMB PARIS ROUBAIX TUBULAR
> 
> TUBULAR TIRES


Off-topic question regarding these tires:

Do these tires become stronger/better by aging them?


I read Lance Armstrong raced on tires that were _at minimum_ 5 Y.O.


----------



## Chris-X

cda 455 said:


> Off-topic question regarding these tires:
> 
> Do these tires become stronger/better by aging them?
> 
> 
> I read Lance Armstrong raced on tires that were _at minimum_ 5 Y.O.


Yes

Tubular Tires - Branford Bike - Seattle/Bellevue - Campagnolo Pro Shop

How a handmade tubular is made - YouTube

No

Tubular Fables by Jobst Brandt


----------



## carlosflanders

fwiw, Most of what salsa has written concerning physics is wrong.

No way you can feel a speed difference in heavier or larger tires if the weight difference is 100g or width difference is 2 mm.

I have done a lot of racing in the past few years with both 23mm and 25mm tires. Michelin Pro Race 3s (which measure 24mm and 27mm). There is a difference. The larger tire gives a slightly smoother ride. Not a night and day difference, but perceptible. At the end of long road races I was a lot less fatigued and had quite a bit left for the manic pace and sprint of the last couple of miles. I also did a few crits where the last corner was pretty rough, or there were some manholes. I could roll through without worrying, whereas others were choosing a less optimal line to avoid possibility of pinch flatting. The wider tires definitely were an advantage. Only if the surface was excellent would I go for 23 mms.

I had several podiums this year on 26 mm tubulars on box-section rims - including a couple of TTs.

Less fatigue plus more confidence in cornering aggressively equals better results.


----------



## Salsa_Lover

Carlos I do believe it is true most that you say

- that you can't perceive a difference
- that you can have better results on bigger and heavier tyres ( due to less fatigue )

but what I say about physics is absolutely true. The gravitational force pushes you down and back and this gravitational force is a composite of your mass the gravitational acceleration you have to overcome and the angle of the slope. Well the only part wrong is that for simplicity I omited the angle component sin(ɵ) this is what makes it harder when it is steeper. but the concept is the same.

the fact that your own acceleration is cancelled by the gravitational acceleration doens't mean there is not acceleretation, in fact it is there permanently in a differential way. 

That is in fact the main reason what makes climbing harder than riding in flat terrain.


----------



## motobecane69

Salsa_Lover said:


> Carlos I do believe it is true most that you say
> 
> - that you can't perceive a difference
> - that you can have better results on bigger and heavier tyres ( due to less fatigue )
> 
> but what I say about physics is absolutely true. The gravitational force pushes you down and back and this gravitational force is a composite of your mass the gravitational acceleration you have to overcome and the angle of the slope. Well the only part wrong is that for simplicity I omited the angle component sin(ɵ) this is what makes it harder when it is steeper. but the concept is the same.
> 
> the fact that your own acceleration is cancelled by the gravitational acceleration doens't mean there is not acceleretation, in fact it is there permanently in a differential way.
> 
> That is in fact the main reason what makes climbing harder than riding in flat terrain.


exactly, it also explains why as a 240lbs clyde on a flat surface I can go as fast as my 180lb friends but they blow me away as soon as we hit a hill!!!


----------



## BeerDrinkingDad

Salsa_Lover said:


> Carlos I do believe it is true most that you say
> 
> - that you can't perceive a difference
> - that you can have better results on bigger and heavier tyres ( due to less fatigue )
> 
> but what I say about physics is absolutely true. The gravitational force pushes you down and back and this gravitational force is a composite of your mass the gravitational acceleration you have to overcome and the angle of the slope. Well the only part wrong is that for simplicity I omited the angle component sin(ɵ) this is what makes it harder when it is steeper. but the concept is the same.
> 
> the fact that your own acceleration is cancelled by the gravitational acceleration doens't mean there is not acceleretation, in fact it is there permanently in a differential way.
> 
> That is in fact the main reason what makes climbing harder than riding in flat terrain.


What I believe the original argument was about is whether or not these "accelerations" genuinely play a material role in anything. I'm pretty sure all parties here will admit that at some level, nearly everything is accelerating in some fashion. What you (Salsa) are losing sight of is the (in)significance of these accelerations.

There is a commonly held myth that "rotating mass" is the equivalent of 3x static mass. The reality is that with the small differences in rim/tire mass you're talking about here, not only are the sensations likely imperceptible, they're wholly immaterial. 

Granted, I wouldn't race on my studded wire beaded winter commuter treads but in this case we're talking about tires weighing 4-6 times that of a traditional racing tire.

If you can poke holes in the math at AnalyticCycling you're wasting your time arguing on this message board.

Have a great day!


----------



## carlosflanders

Salsa_Lover said:


> the fact that your own acceleration is cancelled by the gravitational acceleration doens't mean there is not acceleretation, in fact it is there permanently in a differential way.


Not meant as as anything personal, but this is totally wrong.


----------



## Guest

salsa lover said:


> that is actually wrong.
> 
> your postulate says that if you are going on steady speed uphill, theoretically there is no acceleration right ?


My point is that there is no _angular_ acceleration of the wheels if riding at a steady speed, regardless of incline. Riding uphill you are correct there is linear acceleration due to gravity that must be continuously overcome by the rider. 

Acceleration due to gravity only depends on the actual _mass_ of an object, whether that mass is "rotating mass" or not is irrelevant. 1 gram in the wheels is no different than 1 gram anywhere else.

If I were to hypothetically drop two identical wheels in vacuum chamber (ie, neglecting differences due to aerodynamic drag) -- one of them rotating like crazy, the other perfectly still -- and a brick weighing the same as each of those wheels, all three would fall at exactly the same rate. Rotation has no effect on the force due to gravity (mg) 





kbwh said:


> I do not have to accellerate to keep my vertical speed constant (given no change in incline). Thus the angular velocity of my wheels do not change and it does not matter where the weight of my bike sits.
> 
> What happens in that nasty hairpin that suddenly gives me 20% to battle instead of 6% is another story.


KBWH is absolutely correct here. 

Rotational intertia (resitance to change in the rotation rate (RPMs) of the wheels) actually does matter more on climbs more than any other situation in cycling because your speed is more likely to vary with changes in the terrain, hairpins, etc compared to riding on the flats. But only when your speed is actually changing will the weight in the wheels "count [up to] double" compared to weight anywhere else



> There is a commonly held myth that "rotating mass" is the equivalent of 3x static mass. The reality is that with the small differences in rim/tire mass you're talking about here, not only are the sensations likely imperceptible, they're wholly immaterial.


Equvialency of 3x or greater is a myth (I've heard factors as high as 8x before) -- but rotating mass does require more work to [net] accelerate than static mass, as much as 2x more.

Whether 2x ~100g is particularly significant is another matter entirely...


----------



## KensBikes

Rogus said:


> I think someone else called this light bulbing. :idea:
> 
> OK, so it's not solely because of it being a 28mm or larger tire, but becasue the tire width was too large for the rim. Makes sense. Is the opposite a problem? Where's the point where a tire is too narrow for a rim?


Another issue with having a rim too narrow is that caliper brakes might not open enough to remove the wheel without deflating the tire. You can put a 32 mm Pasela on a standard-sized race rim like an Open Pro, but you may well have to change brake adjustment or deflate the tire every time you want to pull the wheel, since most brake QR features don't give you more than about 8 mm of opening.


----------



## NJBiker72

Interesting i deflated 25s to get them off my Secteur .


----------



## kbwh

And your brake quick releases were set up properly so that you could use them as per intent?

Sorry to ask, but I see a lot of SRAmano-equipped bikes ridden with open QRs.


----------



## PlatyPius

Salsa_Lover said:


> nice touring bike.... SPD pedals and all...
> 
> why you people keep insisting citing the wrong conditions/roads/cobblestones etc. if you are riding off road, or gravel paths, or north french cobbles or wathever, that's great, I go on that on my commuter with Vittoria randoneurs 32s or on my cross bike with Grifos....
> 
> in this thread we are talking "road bikes" here, you know, roads right ?, asphalt, tarmac etc.


Yes, we are talking about road bikes. Note that it's ROAD bike review, not RACING bike review.

If gravel roads aren't roads, then what are they? If I pull up a county map of Putnam County Indiana, there are lots of gravel roads with names like "County ROAD 350 N."

Regardless, many of the roads in many of the states of the US are in terrible shape this year. A 700x23 beats you death on the roads around here. 700x25 is better. Less bouncing, less jarring, less fatigue to the rider (ya know that's why bike shorts are lycra, right? Keeps the muscles from bouncing around as much, thereby reducing fatigue).

Me, I have Clement Strada 700x28 on my Cyfac. When my ride doesn't shake me to death or just hurt a lot, I'll ride longer and occasionally faster.

Until the 80s and beyond, almost all road bikes in the US had 27x1-1/4" tires. Then everyone decided they were a racer and needed racing tires.


----------



## PlatyPius

kbwh said:


> And your brake quick releases were set up properly so that you could use them as per intent?
> 
> Sorry to ask, but *I see a lot of SRAmano-equipped bikes ridden with open QRs.*



Ditto. WTF is up with that? Are people just stupid, or what? I always close them. Some complain that the brakes are too tight then. So I adjust them properly, leaving the release closed. There's a shop around here somewhere that sets the brakes up with 5mm of lever travel, apparently.


----------



## NJBiker72

kbwh said:


> And your brake quick releases were set up properly so that you could use them as per intent?
> 
> Sorry to ask, but I see a lot of SRAmano-equipped bikes ridden with open QRs.


I believe so. Was not a big deal, just deflate slighlty and remove.


----------



## Salsa_Lover

PlatyPius said:


> Yes, we are talking about road bikes. Note that it's ROAD bike review, not RACING bike review.
> 
> If gravel roads aren't roads, then what are they? If I pull up a county map of Putnam County Indiana, there are lots of gravel roads with names like "County ROAD 350 N."
> 
> Regardless, many of the roads in many of the states of the US are in terrible shape this year. A 700x23 beats you death on the roads around here. 700x25 is better. Less bouncing, less jarring, less fatigue to the rider (ya know that's why bike shorts are lycra, right? Keeps the muscles from bouncing around as much, thereby reducing fatigue).
> 
> Me, I have Clement Strada 700x28 on my Cyfac. When my ride doesn't shake me to death or just hurt a lot, I'll ride longer and occasionally faster.
> 
> Until the 80s and beyond, almost all road bikes in the US had 27x1-1/4" tires. Then everyone decided they were a racer and needed racing tires.


You have a good point here.

I am spoiled by our pristine roads... That's why there is always road work somewhere around....


----------



## rsilvers

Updating 2011 thread with 2015 info:

http://www.conti-tyres.co.uk/conticycle/road_tyres/GP4000sII/WideRaceTyreTest_TOUR_Magazine_2014.pdf

Ask Nick: Prescription lenses in the rain, Roubaix tire options, and more - VeloNews.com

https://janheine.wordpress.com/2014/01/01/tires-how-wide-is-too-wide/

https://janheine.wordpress.com/2012/01/30/the-downsides-of-wide-tires/

https://janheine.wordpress.com/2011/08/30/the-dangers-of-narrow-tires/

Tyre trends: what the teams are using for Paris-Roubaix | CyclingTips


----------



## ziscwg

rsilvers said:


> Updating 2011 thread with 2015 info:
> 
> http://www.conti-tyres.co.uk/conticycle/road_tyres/GP4000sII/WideRaceTyreTest_TOUR_Magazine_2014.pdf
> 
> Ask Nick: Prescription lenses in the rain, Roubaix tire options, and more - VeloNews.com
> 
> https://janheine.wordpress.com/2014/01/01/tires-how-wide-is-too-wide/
> 
> https://janheine.wordpress.com/2012/01/30/the-downsides-of-wide-tires/
> 
> https://janheine.wordpress.com/2011/08/30/the-dangers-of-narrow-tires/
> 
> Tyre trends: what the teams are using for Paris-Roubaix | CyclingTips


You almost got fired because it's not thread dredge tuesday. If the post was from 2010, you'd be on the message board unemployment line


----------



## rsilvers

I have heard that posting in old threads is controversial, but I don't really understand the logic.

I found the thread by searching for the 28mm tire topic. I then did the research and found some updated information. It would seem helpful to other people who find the thread to have the updated info. Not to mention that the thread already contains notifications to people who are interested in the subject.

Is it really preferred to start a new thread? If posting in threads of a certain age is bad, then why not set the forum option to auto-lock any thread after 5 years?


----------



## wgscott

Rogus said:


> I realize not everybody agrees that 25mm tires are faster/better than 23mm, but IF YOU DO, then why aren't 28mm tires considered even better? Certainly there's a point where weight and aerodynamic drag becomes an issues but where is that point?


Basically, they are just a wee bit too narrow for what I want to do, so I took mine off, put them on another bike, and bought 35 mm Clement XPLOR USH. Now I don't have to ride on roads all the time.

Always make the most of a necropost


----------



## rsilvers

The crossover point will have to do with how fast you ride and how wide your wheels are.

I have Dura Ace C24 TL wheels, and they are 20.8mm wide on the outside. Shimano recommends 23, 25, or 28mm tires.

Going from the width of the wheels, I probably should have stuck with 25mm tires - at least from an aero point of view. I got 28 anyway, figuring that I average less than 20 mph on my rides.

I am not sure if I made the right decision or not but I am looking forward to having less effect from rough roads. I do slow down a lot on certain roads, and I think 28mm will help me there more than the loss due to drag of 28 vs 25.


----------



## robt57

rsilvers said:


> I have heard that posting in old threads is controversial, but I don't really understand the logic.



You coulda just started a new tread and got chastised for starting a thread which the subjex has been discussed ad nauseam. God forbiid you posted said new tread outside the tires/wheels sub-forum in that regards. Although that I can get behind more . . .

Then, there is the fun you could have mis speelin and trunucating a few words intentioally and watch the sphincter locked critiques witch will follow...


----------



## rsilvers

I try to be considerate. On the UK forums I spell tire as tyre so they know what I mean.


----------



## ergott

Hey I've been running primarily 28mm tires the last 2 years and even started using 42mm (650b) this season. Same riders I ride with tell me to ease up on flat/rolling terrain so I don't think I'm significantly slower at all. Best of all I enjoy looking around at the scenery instead of where the next pothole will be.

I haven't thrown out all my "skinny" tires. I have one road bike that won't accept anything over a 25mm (actual width). I currently use Schwalbe One TL 23mm tires on it and the ride is fine so long as I don't try to compare it to my other setups.

If you haven't ridden a 650bX42mm setup on the road I highly recommend it. It's pretty darn fast and the ride quality is a dream.


----------



## wgscott

robt57 said:


> and watch the sphincter locked critiques witch will follow...


which witch is that?


----------



## Jay Strongbow

Regardless of what the science says about the weight and aero that wouldn't be the whole story.
Fatigue caused by smaller tires and it's impact on ability to generate power would have to be considered (obviously road condition and length of ride are important variables there).

Another over looked advantage of bigger tires is cornering. I'm not sure if I lack skill or bravery or both but I kind of suck at cornering compared to many more experienced riders I ride with and losing speed and needing to accelerate coming out of a corner to catch back on is a really big deal and bigger tires with less PSI definitely reduce if not eliminate the problems there.


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## jnbrown

20mm tires @ 140 PSI works best for me.


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## dcgriz

ergott said:


> ...snipped...
> 
> If you haven't ridden a 650bX42mm setup on the road I highly recommend it. It's pretty darn fast and the ride quality is a dream.


Curious for your input on how significant of an improvement you see on comfort between 700cx32 and 650bx42 on relatively smooth tarmac roads.
How would you rate the difference in agility between the two?
Im contemplating the choice between 700cx35-38 vs. 650bx42 for road use. The closest I have to compare is my 29er which rolls over everything but is over-stable for road use.


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## ziscwg

rsilvers said:


> *Is it really preferred to start a new thread?* If posting in threads of a certain age is bad, then why not set the forum option to auto-lock any thread after 5 years?



If you start new thread, CX will rip on you for not using the search button and link to 4 similar threads. 

So, you just can't win. I would suggest riding more and posting less. No one can give you crap as you drop them climbing that mtn.


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## ergott

@dcgriz 

Problem for me is 700X32+ starts getting into more and more toe overlap, especially since I use fenders. I ride a 53cm-54cm bike. I rode the same bike with only 700X28 and fenders (beauty of disc brakes). I plan on riding said bike with bigger 700c tires next season after I take the fenders off.

One experience I'm trying to figure out is off-axis contact patch. When you use a wider tire, the contact patch is more off-axis in corners. I've been chatting David Kirk about it. My bike with the above mentioned tires has a trail of 62mm so some of the difference can possibly be contributed to that. I always ride bikes with higher trail numbers and I definitely feel a different experience with this bike and the wide tires.

The idea is that a bike with significantly wide tires in a corner wants to continue turning or even get tighter as a result. It's a more significant thing with fat bikes. It's only a mild difference that takes a ride to get re-acclimated to from my other bikes. I corner with just a bit more pressure/lean on my inside hand to modulate the corner if that makes sense. Once acclimated, I can corner pretty well on the bike.

Otherwise, I've ridden my cross bike with 32s and the problem comparing is that I was using a file tread with some lugs on the edges (Michelin Jet). This was at a few D2R2s that have a fair amount of pavement. The lugs led to some squirreling that would effect my judgement of the tire size in general

I can say that I use another bike with 23mm and 28mm tires. I feel real planted on that bike regardless, but I know that's a smaller difference than we are taking about with the other tires.

Bottom line, I think the geo of the bike (trail, tire flop, et al) will probably just as much of an impact than the difference between the tires in your question. That's my opinion and I'm still in the early stages of studying this.


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## robt57

wgscott said:


> which witch is that?


Witch/witch ever one educes the sphincter lock best, I thought that was obvious...


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## dcgriz

@ergott

I'm on 700c road tires. Nothing less than 25mm anymore, mostly 27s-28s and 32 on the upper end. Different bikes with HT angles ranging between 72 to 73 deg, chainstays between 41 and 42 cm, some toe overlap on the sportier ones, no toe overlap on the fendered one. All have road forks with medium trail ranging from 56 to 59. Bike size is 58x61 for all. Tires are GP 4ksii, Challenge PR and Challenge SB, all with latex tubes. I've described what I use to make most of what I'm about to say and confirm that definitely, all else being equal or close to equal, wider tires are more stable and tend to be more on rails on the turns, at least to my perception. Holding the line is both good and not good depending what you do at the time. Descending at speed they will hold very stable but will do the same on a turn; I find the wider the tire the greater the effort to change its direction mid-turn.
I never had a low trail bike to see how it compares but what I'm currently contemplating is a low (or lower) trail with 650bx42. I'm not sure on the trade-offs but this setup is supposed to generate more agility in handling than a fat 700c. 
What is really stopping me from the 650b route is the very poor choice on rims and very limited choice on high performance tires. KP is supposed to come out with a new rim maybe around February but not certain yet. Tires is really a one man show. Not fond of lack of choices.


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## ergott

I have Nox Skyline which are perfect for this. Pressure is under 40 anyway. 

My tires are Soma Grand Rando (the lighter, green label). They have been performing wonderfully for me. People rave about the Compass offerings. 

Schwalbe will have tubeless real soon so it's only getting better.


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## ziscwg

rsilvers said:


> I try to be considerate. On the UK forums I spell tire as tyre so they know what I mean.


I tyre of you talking about tires over there.


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## BikeLayne

A very slow tire is one that gets a flat. You cannot make up that time over a normal ride. Another reason to lose time is rough roads and excessive maneuvering of the bike or your body over chug holes and rough patches. Anyway around here the 28mm tire is very common. However all sizes are seen on the road. I can run 28mm tires without fenders or 25mm tires with fenders. I am thinking of running 28mm and since I have to remove the wheels to put the fenders on anyway I would just put on my back up wheels with 25mm tires for riding in the rain. 


As far as aerodynamics are concerned I do not care. I ride in a side wind anyway.


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## dcgriz

ergott said:


> I have Nox Skyline which are perfect for this. Pressure is under 40 anyway.


Interesting rims, specially their new road/CX. On their website they mention the bead hook vs. no hook rims and seem to suggest tires wider than 45 mm for the hookless. Thoughts?



ergott said:


> My tires are Soma Grand Rando (the lighter, green label). They have been performing wonderfully for me.


Had not looked at Soma for tires before. Good to know.



ergott said:


> People rave about the Compass offerings


In my experience, the tires are good but when an issue occured their customer service was non-existent; they didn't even bother respond at all to any of the repeated questions I raised and that really bothers me. This alone makes me look elsewhere for tires and never to recommend them again.


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## Lombard

rsilvers said:


> The crossover point will have to do with how fast you ride and how wide your wheels are.
> 
> I have Dura Ace C24 TL wheels, and they are 20.8mm wide on the outside. Shimano recommends 23, 25, or 28mm tires.
> 
> Going from the width of the wheels, I probably should have stuck with 25mm tires - at least from an aero point of view. I got 28 anyway, figuring that I average less than 20 mph on my rides.
> 
> I am not sure if I made the right decision or not but I am looking forward to having less effect from rough roads. I do slow down a lot on certain roads, and I think 28mm will help me there more than the loss due to drag of 28 vs 25.


I went to 28mm tires on both my road bikes and never looked back. Ride quality is so much nicer and I don't notice any difference in speed between the two. The aero and weight advantage with 25s vs. 28s is negligible.


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## ergott

dcgriz said:


> Interesting rims, specially their new road/CX. On their website they mention the bead hook vs. no hook rims and seem to suggest tires wider than 45 mm for the hookless. Thoughts?
> 
> 
> Had not looked at Soma for tires before. Good to know.
> 
> .



Somas are made by Panaracer so that's a good thing.

My tires measure a bit over 43mm on those rims. I think that close enough. I've sent pics to Nox showing the project and they loved it. I just won't do getto tubeless even with the low pressure. With tubes I feel confident and the ride is awesome. Love chasing down group rides when they are all on their go fast bikes and I roll up with this.


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## dcgriz

Bike setup looks great. Exactly what I'm thinking about. The only thing I would do different on mine would be an Edelux instead of the Lumotec, and I don't have a good reason for it other than habit.


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## ergott

Mine's Luxos-U with the USB charger.


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## dcgriz

Heard good things about these lights and I understand they got away from the leaky switch with the USB connector. How's the underside sealed?
Paired it with the Son28? Can't tell from the pick.


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## Easyup

It is easy for me. When riding my usual daily route with my occasional neck pain flaring up my Tange Prestige framed Pinarello with the 28s is always what I pull out for the day. I have clinchers, tubulars, 23s, and 25s. If the neck is really bad I sometimes go to a MTB w/ Bontrager Hanks or worse case the trainer.


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## ergott

Yes, Son 28.

So far I have a few really wet, rainy rides (today) with it and haven't had any water get in the light. I do use fenders so they aren't being sprayed from underneath. The charger I have is the 2nd gen, not the 3rd which is current. Again, no water so far.

I can't even begin to tell people how much more confidence inspiring wider tires like these are. When riding in the dark, it's raining, there are cars passing, and there are leaves on the ground there's a lot to pay attention to. The hidden potholes aren't as big a deal and the tires give much more grip.


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## dcgriz

Totally agree on the utility of the wider tires. I've been using them for a while now on my commuting bike. Im not certain yet but it seems to me, so far at least, that over 700cx35 the feel starts becoming rather sluggish, more like a 29er, in addition to needing more to start moving them. Thus the look into the 650b.

The bike looks sweet, BTW. I am wondering if you would recommend the 32x32 Skylines for a combined weight of around 250 lbs.


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## ergott

Hmmm. I have been north of 180 and easily put about 20 on the bike. I would check with them.

In other news, I ordered this light and can't wait to try it out. 

Busch & Müller: LUMOTEC IQ-X


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## Lombard

dcgriz said:


> Totally agree on the utility of the wider tires. I've been using them for a while now on my commuting bike. Im not certain yet but it seems to me, so far at least, that over 700cx35 the feel starts becoming rather sluggish, more like a 29er, in addition to needing more to start moving them. Thus the look into the 650b.


No and maybe.

The width of the tire itself will not significantly slow you down. In fact, wider tires actually have less rolling resistance than narrow tires. Of course this is offset by wider tires weighing more and having more aero drag.

Speaking of weight, that will make starts more sluggish, but once up to speed, it will be irrelevant.

That being said, one thing that WILL slow you down more than the width of a tire is whether the tire has a tread. I have 700x38c Kenda Kwests on my hybrid and I can tell you that once up to speed, it rolls quite well!

http://www.amazon.com/Kenda-Kwest-H...id=1446130661&sr=1-3&keywords=kenda+700+x+38c 

They also make a 700x40c. I would try these before spending the $$ for a set of 650 wheels.


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## dcgriz

ergott said:


> In other news, I ordered this light and can't wait to try it out.
> 
> Busch & Müller: LUMOTEC IQ-X


Even brighter than the Luxos and quite wide beam. Pretty slick.


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## crit_boy

Lombard said:


> No and maybe.
> 
> The width of the tire itself will not significantly slow you down. In fact, wider tires actually have less rolling resistance than narrow tires. Of course this is offset by wider tires weighing more and having more aero drag.


You know the "wider tires actually have less rolling resistance" mantra applies when combined with the "when both are at the same pressure" (see Velonews). The "at the same pressure" is often ignored in these forums. - Else my 29er with 60 mm tires at 25 psi would be faster than my road bike with 25s at 100 psi.


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## Lombard

crit_boy said:


> You know the "wider tires actually have less rolling resistance" mantra applies when combined with the "when both are at the same pressure" (see Velonews). The "at the same pressure" is often ignored in these forums. - Else my 29er with 60 mm tires at 25 psi would be faster than my road bike with 25s at 100 psi.


Maybe yes, maybe no. Did you read the next paragraph of this article where Lennard Zinn states:

_"And those same readers also often don’t believe that *dropping that bomber pressure* they run in their tires will * reduce their rolling friction*. While I’m sure I can’t convince some people, I can explain in simple terms the reduction in rolling friction with increased tire width."_

A bit contradictory to what you said?

Not to mention I would guess your 29er probably has knobbies or some other aggressive tread pattern. Sort of an apples-to-oranges comparison.


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## ziscwg

ergott said:


> Hmmm. I have been north of 180 and easily put about 20 on the bike. I would check with them.
> 
> In other news, I ordered this light and can't wait to try it out.
> 
> Busch & Müller: LUMOTEC IQ-X





dcgriz said:


> Even brighter than the Luxos and quite wide beam. Pretty slick.


that light is bolt on to the brake mount????

I love the power of that one on 180 lux. I'm sure that translates in 40000000000 Lumens.


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## ergott

Yeah, to the brake bridge hole by default. You can always mount it elsewhere with some craft.


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## Enoch562

If I was looking for a tire that was a little bigger than Pro4 Michlin 25 but still had that "performance tire feel", what would be the recommendations? FWIW, I can fit 40 CX tires all day. I'm using a Pacenti SL 25 disc rim.


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## robt57

Enoch562 said:


> If I was looking for a tire that was a little bigger than Pro4 Michlin 25 but still had that "performance tire feel", what would be the recommendations? FWIW, I can fit 40 CX tires all day. I'm using a Pacenti SL 25 disc rim.



Grand Prix 4KS 28mm?? I think I read on a wide rim they are like 31mm??

My 25 casing Michelins are 28-9mm on a wide rim. 2mm ain't mush more maybe...


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## Mandeville

My 2015 stock Trek Domane came with 25mm. After several thousand miles on the them when I replaced them with the exact same model tire but size 28mm. It turned out the 28mm were definitely significantly quicker on climbs and appear to be faster on the mostly flats in terms of overall average speed for the distance ridden. 

They ride more comfortable too but are slower if attempting to accelerate heavily or quickly. 

YMMV.


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## crit_boy

Lombard said:


> Maybe yes, maybe no. Did you read the next paragraph of this article where Lennard Zinn states:
> 
> _"And those same readers also often don’t believe that *dropping that bomber pressure* they run in their tires will * reduce their rolling friction*. While I’m sure I can’t convince some people, I can explain in simple terms the reduction in rolling friction with increased tire width."_
> 
> A bit contradictory to what you said?
> 
> Not to mention I would guess your 29er probably has knobbies or some other aggressive tread pattern. Sort of an apples-to-oranges comparison.


“’Wider is faster’ holds for clincher and tubular tires under the condition *of the same air pressure *(emphasis added, from velonews article above). 

Small diameter tires have a higher rolling resistance *at the same tire pressure* (emphasis added) - Schwalbe

At the end of the day, the facts are the facts; a 25mm tire experiences less rolling resistance than a 23mm tire *at the same air pressure*
(emphasis added) - Competitive Cyclist 

yes, a wider tire of similar construction will have lower rolling resistance than a narrower one *at the same pressure* (emphasis added)- Sheldon Brown 

wider tires will have shorter contact patches and, hence, less tire deflection; *if the tire pressure is the same* (emphasis added) - Another velonews article


But, you're right. Wider tires are faster - no qualifiers needed.


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## pacificaslim

If a 25 has lower rolling resistance at the same pressure as a 23, then the 25 surely still has lower rolling resistance at some amount of lower pressure than the 23 as well. It's not like it magically becomes better only once that last 1psi is put into the 25. It surely surpassed the 23s rolling resistance before that point. 

I mean, let's say one runs the 23s at 100psi. If one was to inflate the 25s to 100psi, then all sources agree he'll have lower rolling resistance. If he only inflate the 25s to 75psi, he probably has more rolling resistance. But what is the pressure on the 25 that will equal the rolling resistance of the 23? Is it 85? 90? If we knew that point we could then decide what our goal is: to have the same rolling resistance we had on 23s but with a more comfortable ride thanks to the lower pressure, or put equal pressure into the 25 and likely not be any more comfortable, but be faster than we would be on the 23s thanks to lower resistance.


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## Lombard

pacificaslim said:


> If a 25 has lower rolling resistance at the same pressure as a 23, then the 25 surely still has lower rolling resistance at some amount of lower pressure than the 23 as well. It's not like it magically becomes better only once that last 1psi is put into the 25. It surely surpassed the 23s rolling resistance before that point.
> 
> I mean, let's say one runs the 23s at 100psi. If one was to inflate the 25s to 100psi, then all sources agree he'll have lower rolling resistance. If he only inflate the 25s to 75psi, he probably has more rolling resistance. But what is the pressure on the 25 that will equal the rolling resistance of the 23? Is it 85? 90? If we knew that point we could then decide what our goal is: to have the same rolling resistance we had on 23s but with a more comfortable ride thanks to the lower pressure, or put equal pressure into the 25 and likely not be any more comfortable, but be faster than we would be on the 23s thanks to lower resistance.



This is assuming that higher tire pressure is always faster. Not quite. In an ideal world where all road surfaces are closed course and track smooth, yes, more pressure is faster. However, in the real world of real road conditions - rough pavement, chip seal, etc which are found in numerous urban and rural areas alike, lower pressure will roll faster due to less energy being lost to vertical motion. I believe most of us encounter these conditions way more than the ideal conditions I mentioned.

Lower pressure also has the added benefit of a more pleasant ride regardless.


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## jnbrown

Why not?
Because they are huge, feel slow, unnecessary.
Even on my tandem I use 23 on the front and 25 on the back, we weigh 250 and I use 100 PSI. Had a Michelin Pro4 endurance 25 on the back and it measured 29mm, switched it out to Conti GP4000S.


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## rruff

Lombard said:


> However, in the real world of real road conditions - rough pavement, chip seal, etc which are found in numerous urban and rural areas alike, lower pressure will roll faster due to less energy being lost to vertical motion.


Up to what point is the question. 

I recall seeing a study by Schwalbe on MTB tires and they said 20psi (the lowest they tried) was fastest rolling even on gravel. But gravel wasn't well defined. 

Velonews published some tests done at Wheel Energy on a textured drum. Minimum resistance was in the 100-110psi range, but did not change much outside that range. Tires with a poor Crr to begin with fared worse at lower pressure. 

I recall another test where vibration response was measured, and tire size had little effect, rather pressure was dominant. So you'll get about the same ride with 23s at 80psi vs 28s at 80psi. 

The 28s will tend to have less rolling resistance at the same pressure and also better pinch flat resistance, but aero resistance will be higher and sensitivity to crosswinds will be higher. The aero resistance increase will be more than the Crr decrease, unless you are going slow.


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## Lombard

rruff said:


> Up to what point is the question.
> 
> I recall seeing a study by Schwalbe on MTB tires and they said 20psi (the lowest they tried) was fastest rolling even on gravel. But gravel wasn't well defined.
> 
> Velonews published some tests done at Wheel Energy on a textured drum. Minimum resistance was in the 100-110psi range, but did not change much outside that range. Tires with a poor Crr to begin with fared worse at lower pressure.
> 
> I recall another test where vibration response was measured, and tire size had little effect, rather pressure was dominant. So you'll get about the same ride with 23s at 80psi vs 28s at 80psi.
> 
> The 28s will tend to have less rolling resistance at the same pressure and also better pinch flat resistance, but aero resistance will be higher and sensitivity to crosswinds will be higher. The aero resistance increase will be more than the Crr decrease, unless you are going slow.



What do you define as slow?

Also, how much more aero drag could a 28c vs. a 23c tire have in relation to the much larger aero drag of the rider?

And how "textured" was this drum that the experiments were done on? I would be curious how well variable real road conditions were simulated here. I can assure you that while riding on patched potholes, minimal resistance will be obtained at less than 100-110psi.


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## rruff

Lombard said:


> Also, how much more aero drag could a 28c vs. a 23c tire have in relation to the much larger aero drag of the rider?


It depends on many factors. In TTs I use a 20mm tire on rims with a 26mm wide brake track. That isn't by accident. It's been measured. 

Rims like the Kinlin XC279 and Pacenti SL23 have good aero properties with a 23mm tire, but not if you go wider. When there are 50mph gusts I can feel the difference in crosswinds. 

The textured drum looked similar to the photo below. Several mm tall bumps. Another factor with roads though is the softness of the tar. Chipseal is usually pretty soft. 

When you say resistance is minimized with lower pressure, how did you measure it?


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## rsilvers

rruff said:


> The aero resistance increase will be more than the Crr decrease, unless you are going slow.


While I don't know the crossover speed, I heard someone guess 26 mph, and that seems believable. If so, I would say that the Crr decrease wins unless you are going very fast. The average speed for a male on Strava is something like 16.4 mph, and Strava people are almost certainly faster than the biking population as a whole. Average female speed is around 13.5.


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## rruff

rsilvers said:


> While I don't know the crossover speed, I heard someone guess 26 mph, and that seems believable.


It depends on the wheels, the tires, and the rider. If you are going 26 mph you are definitely in the zone where aero trumps everything. I would say anything over 15 mph.

And why bring up Strava? Are they racing? If you aren't racing (officially or not) what does it matter? Ride your MTB with fat slicks at 20 psi.


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## rsilvers

I bring up Strava because it collects speed statistics on thousands of riders, so it is a good place to find data on how fast people ride.

If I rode a MTB bike, I would not be able to complete club rides with the other people. But yes, I can ride my MTB when I am alone.

I care about my average speed for riding just like I care about my average pace while running - to track my improvement over time, keep me motivated, and predict what I could do if I were racing.


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## Lombard

rruff said:


> It depends on the wheels, the tires, and the rider. If you are going 26 mph you are definitely in the zone where aero trumps everything. I would say anything over 15 mph.


Well, OK, if you are a racer, this makes sense.



rruff said:


> If you aren't racing (officially or not) what does it matter? Ride your MTB with fat slicks at 20 psi.


Bad analogy. The world isn't black or white, but somewhere in between. I and most the people I ride with are endurance road riders who average around 14-15mph on a 50 mile moderately hilly ride. We are not racers, but we are not riding in the woods either.

I think I can be pretty safe in saying that while I'm climbing a 14% grade at 6mph, aero doesn't come into play much. However, if I am climbing a grade like this that is full of random pavement anomalies, a wider tire that I can use less pressure in will only help me. For most of my riding needs, I have found that 28c tires with 70psi front and 100psi rear works best for me for both efficiency and comfort.


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## harryman

> If I was looking for a tire that was a little bigger than Pro4 Michlin 25 but still had that "performance tire feel", what would be the recommendations? FWIW, I can fit 40 CX tires all day. I'm using a Pacenti SL 25 disc rim.


I put a set of Schwable ones on in August, they're very nice tires, and measure just a hair under 28mm on Sram Rise 60s, 21mm internal width. I came off Conti 4 seasons 28's, wich measure pretty small.

I don't race, can keep up with the faster guys rolling in the flats on Wednesday Morning Worlds and am not particular aero in shape. The roads around here suck, so 28's @ 75-85 psi are way more comfy IMO. I used to run 23's and 25's, but never again. I'm a mtber, so they don't look all that fat to me. lol

I also run wider gravel tires in the winter, they start slowing down as knobs are added for sure.

I'd also look into mountain bike rims for 650b, there's plenty of offerings.


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