# Tarmac 700 x 25



## Caneray (Nov 21, 2012)

Anyone tried running 700 x 25 tires on a Specialized Tarmac?
Thinking about trying it and just wondered...


----------



## aroadbike4u (Jan 27, 2013)

It'll work. Will you notice a huge difference in ride quality? Probably not. 

Not sure what model Tarmac you're riding, but they don't impress me as having a particularly refined ride. If the rims on your wheels happen to be either wider or tubeless compatible then you have a little more room to improve ride quality.

Just a change in the brand of tire might make a noticeable difference. Continentals - nice but kind of hard riding. Michelins Pro 4 or Vittoria Open Corsa - slightly more supple road feel.


----------



## scottma (May 18, 2012)

A friend of mine just put Conti 4000s 25c on his Tarmac SL4 to try out and see if he likes the change. They fit but he said they are "big ugly and heavy" LOL. He is used to lighter 23c. They are on 19mm wide rims. We are riding a century this weekend so it will be a good test.


----------



## Caneray (Nov 21, 2012)

Riding SL4 Expert. Coming off riding Roubaix and was just interested to get a take on whether anyone had done it.Not looking for a "refined ride" (had the Roubaix for that) just perhaps a wee bit more compliant.


----------



## Used2Run (Sep 5, 2012)

I have a 25mm Gatorskins on my Tarmac. It rides well and I'm happy with it. I also don't think it looks bad.


----------



## PJ352 (Dec 5, 2007)

I'm running 25c Conti 4000s's on my '08 Tarmac Comp and think they made a noticeable difference in ride quality. Gotta remember the second half of this equation.. tailor tire pressures to match tire size, rider weight and road conditions.


----------



## jeffmuldoon (Aug 12, 2011)

25C works perfectly fine on my Tarmac SL4.


----------



## Typetwelve (Jul 1, 2012)

I'm actually heading in the other direction on my '12 Tarmac...going from a 23mm tire on a 20mm wheel (stocker Specialized turbo tires on a Fulcrum Racing 6 wheel) to a 23mm tire on a 23mm wheel (Conti 4000s on a Rol Race SL wheel)...I'm curious to see what the ride is like.

It wasn't on the Tarmac but I have a Roubaix that I run 25mm tires on and it rides great (RS10 wheel). Getting the wheel off is kind of a pain though figuring the tire is so much wider than the wheel and it sticks at the brake pads even when they're disengaged...


----------



## SystemShock (Jun 14, 2008)

scottma said:


> A friend of mine just put Conti 4000s 25c on his Tarmac SL4 to try out and see if he likes the change. They fit but he said they are "big ugly and heavy" LOL. He is used to lighter 23c. They are on 19mm wide rims. We are riding a century this weekend so it will be a good test.


Heavy? Wha? Conti lists the GP4000 in 25c at 240 grams. Not really a heavy tire.

But if you need lighter 25Cs, they exist:

Michelin Pro4 Service Course in 25c, 215 grams.
Vittoria Diamante Pro Light 25C, 185 grams(!).
Vittoria Open Corsa CX 25C, 220 grams.
Vittoria Chrono, 24C, 175 grams (!).
Grand Bois 'Blue label', 26C, 222 grams.
Schwalbe Ultremo ZX 25c, 215 grams.


Even a lot of the pros are switching to 25mm (tubulars):

*Giro Tech: Rise of the 25mm tire*


----------



## Caneray (Nov 21, 2012)

PJ352 said:


> I'm running 25c Conti 4000s's on my '08 Tarmac Comp and think they made a noticeable difference in ride quality. Gotta remember the second half of this equation.. tailor tire pressures to match tire size, rider weight and road conditions.


I'm 175Lbs and ran at 100-105psi on the Roubaix. Didn't like running softer. It always felt a bit sluggish.


----------



## PJ352 (Dec 5, 2007)

Caneray said:


> I'm 175Lbs and ran at 100-105psi on the Roubaix. Didn't like running softer. It always felt a bit sluggish.


More importantly, running pressures too low runs the risk of pinch flats/ too high actually increases resistance, thus my comment to _tailor_ PSI's based on pertinent factors. Takes some experimenting to find the best compromise.

FWIW, assuming you're running 25c's on your Roubaix, this Michelin chart says you're pretty much spot on with your current pressures. I'd do similar on your Tarmac. 

Michelin Bicycle USA - A better way forward®

I think their explanation of the importance of air pressure sums it up.


----------



## Caneray (Nov 21, 2012)

PJ352 said:


> More importantly, running pressures too low runs the risk of pinch flats/ too high actually increases resistance, thus my comment to _tailor_ PSI's based on pertinent factors. Takes some experimenting to find the best compromise.
> 
> FWIW, assuming you're running 25c's on your Roubaix, this Michelin chart says you're pretty much spot on with your current pressures. I'd do similar on your Tarmac.
> 
> ...


Had not seen that chart. thanks for the link


----------



## looigi (Nov 24, 2010)

That Michelin chart is old-school and CYA. Most recommend lower pressure nowadays.

I'll just mention that rims with wider bead spacing makes the tires physically wider and exhibit some characteristics of wider tires. On my 23mm wide HED rims, 23mm tires measure 25mm, and 25mm tires closer to 27.5-28mm wide. You can adjust pressures based on their installed width, lowering it if the tire is wider.


----------



## Caneray (Nov 21, 2012)

I am old school
Anyone with sense understands that these things are just guidelines and generalizations. There are always going to be variables.


----------



## PJ352 (Dec 5, 2007)

Caneray said:


> Anyone with sense understands that these things are just guidelines and generalizations. There are always going to be variables.


Exactly... and the variables are where the tailoring/ experimenting come into play.


----------



## StillKeen (Oct 4, 2005)

2012 SL2 Comp frame - I've been running Conti Force/Attack 24/22, Conti Race 25, Specialized Armadillo 25, and soon will be onto Michelin Pro Race 25's and Gatorskin 23's. The 25's all fit fine and ride a little softer over rougher road surfaces. I'm a fan of 25's for heavier riders like me on real world roads. I feel it takes me a little closer towards the ride of a Roubaix, the frame I wanted but couldn't afford (as Specialized NZ sold the Tarmac Comp frame on it's own, but for Roubaix the only option was the S-works ... but I'm way off topic here)


----------



## terbennett (Apr 1, 2006)

aroadbike4u said:


> It'll work. Will you notice a huge difference in ride quality? Probably not.
> 
> Not sure what model Tarmac you're riding, but they don't impress me as having a particularly refined ride. If the rims on your wheels happen to be either wider or tubeless compatible then you have a little more room to improve ride quality.
> 
> Just a change in the brand of tire might make a noticeable difference. Continentals - nice but kind of hard riding. Michelins Pro 4 or Vittoria Open Corsa - slightly more supple road feel.


T
Hmmmmm... this baffles me. A Tarmac not having a particularly refined ride? It's not supposed to. A Tarmac is a race bike. That's what it is designed for. If you want refinement, Specialized makes the Roubaix for that. Would you put a softer tuning suspension on a Corvette or a Porsche. High performance does come with some compromises.


----------



## SystemShock (Jun 14, 2008)

terbennett said:


> Hmmmmm... this baffles me. A Tarmac not having a particularly refined ride? It's not supposed to. A Tarmac is a race bike. That's what it is designed for.


Even there, it sort of depends on what kind of race. On a long road race on not-so-great roads, a harsh-riding bike can beat you up. European stage-race racing bikes 'back in the day' often rode pretty nicely, and didn't seem to hold anyone back from being fast. 

I mean, I dunno... I guess we could put a saddle and wheels on an I-beam and crow about how 'efficient' it allegedly is, but I'm not sure a lot of ppl would really want to ride it. 

I know folks who've bought uber-stiff bikes and have found that slowly, they use them less and less, in favor of something that rides better. Don't get me wrong, they still like their 'race' bike, but it somehow winds up not being their 'go-to' everyday ride.

Perhaps you've seen this too, though I don't know what the roads are like where you are.


----------



## dcgriz (Feb 13, 2011)

terbennett said:


> T
> Hmmmmm... this baffles me. A Tarmac not having a particularly refined ride? It's not supposed to. A Tarmac is a race bike. That's what it is designed for. If you want refinement, Specialized makes the Roubaix for that. Would you put a softer tuning suspension on a Corvette or a Porsche. High performance does come with some compromises.


Refinement as in upright geometry and 220mm head tube?


----------



## wabasso (May 18, 2012)

terbennett said:


> T
> Hmmmmm... this baffles me. A Tarmac not having a particularly refined ride? It's not supposed to. A Tarmac is a race bike. That's what it is designed for. If you want refinement, Specialized makes the Roubaix for that. Would you put a softer tuning suspension on a Corvette or a Porsche. High performance does come with some compromises.


Bravo the triumph of marketing. Build a bike that rides like 2x4's bolted together and convince people that a "race bike" is supposed to ride like a chuckwagon. 

Heck of a business model.


----------



## PJ352 (Dec 5, 2007)

wabasso said:


> Bravo the triumph of marketing. Build a bike that rides like 2x4's bolted together and convince people that a "race bike" is supposed to ride like a chuckwagon.
> 
> Heck of a business model.


I'm not questioning the influence marketing has on the bike (and most any) industry, but race geo _does_ influence ride quality. 

If you doubt this, equalize tires/ pressures and go ride a race and touring bike back to back on the same roads. A longer wheelbase will serve to soften a ride, while a shorter one stiffens it. Just a variation of the effect trail has on steering/ handling.

That said, I own two Tarmacs and don't find the ride quality particularly harsh*, but I've been riding long enough to remember Italian race bikes with leather saddles and plastic tape. 

* However, as I mentioned previously, I do tailor PSI's to rider weight, tire size and road conditions. Helps a lot, IMO/ E.


----------



## tom_h (May 6, 2008)

scottma said:


> A friend of mine just put Conti 4000s 25c on his Tarmac SL4 to try out and see if he likes the change. They fit but he said they are "big ugly and heavy" LOL. He is used to lighter 23c. They are on 19mm wide rims. We are riding a century this weekend so it will be a good test.


I've weighed the 23mm = 207 grams and the 25mm = 220 grams.
13g heavier, BFD.


----------



## tom_h (May 6, 2008)

I have an older Sworks SL2, model year 2009.
Installed a 25mm Conti GP4000s on rear, to try it. Alloy rim width = 20.5mm (outside-outside @ brake track).

Side-to-side clearance to chain stays is fine. Clearance to the bottom bracket is tight. 

It is hard to get the wheel forward enough to remove & install it. In fact, I had to substitute a slightly smaller diameter skewer nut on the driveside, because my wheel's original skewer nut was interfering with the Chorus 11 rear derailler's main pivot joint. 

So while I think I'd prefer the 25mm on rear, might revert to 23mm because of this mildly annoying front-rear clearance issue.

Newer Tarmacs might be slightly different (more clearance). Rim width, rear derailleur design, etc, might also be factors.


----------



## SystemShock (Jun 14, 2008)

tom_h said:


> I have an older Sworks SL2, model year 2009.
> Installed a 25mm Conti GP4000s on rear, to try it. Alloy rim width = 20.5mm (outside-outside @ brake track).
> 
> Side-to-side clearance to chain stays is fine. Clearance to the bottom bracket is tight.
> ...



It's sad when a bike can't even really take a 25mm tire. 

2mm more clearance is a big problem for the design team? Yeesh.


----------



## Typetwelve (Jul 1, 2012)

I can't talk of the total ride quality yet as I'm still digesting the differences but having played with a 19'ish mm wheel with a 25mm tire vs a 23mm wheel and a 23mm tire, I can say that so far, the fit on my Tarmac is better with the wider wheel vs the wider tire. I can't help but think the performance will be better too.

I guess I look to,my days as a hard car car guy and my track driving knowledge. If you look at modern "performance" wheel/tire setups vs what were offered 20, 30+ years ago, wheel width has grown and now you see thread sections that are in line with wheel width. This removes sidewall flex issues and drastically improves cornering.

Now, I know that we're talking about bike tires, not cars but I wonder if there's any validity to this in the cycling world. A 25mm tire on a 19mm wheel sticks out quite a bit past the wheel width, I can't help that this would make for less performance overall. (But a more forgiving ride)

Either way...I'm rambling...forgive me.


----------



## willstylez (Sep 15, 2011)

I run Conti 25's on Open Pros for my 2011 S-Works Tarmac SL3 and thoroughly enjoy it. Much better feel than 23's, especially on 75+ mile rides.


----------



## SystemShock (Jun 14, 2008)

Typetwelve said:


> I can't talk of the total ride quality yet as I'm still digesting the differences but having played with a 19'ish mm wheel with a 25mm tire vs a 23mm wheel and a 23mm tire, I can say that so far, the fit on my Tarmac is better with the wider wheel vs the wider tire. I can't help but think the performance will be better too.
> 
> I guess I look to,my days as a hard car car guy and my track driving knowledge. If you look at modern "performance" wheel/tire setups vs what were offered 20, 30+ years ago, wheel width has grown and now you see thread sections that are in line with wheel width. This removes sidewall flex issues and drastically improves cornering.
> 
> ...


The pros are switching more and more to wider tires, like 25mm... so I doubt there's much of a 'performance hit' and/or worse cornering. In fact, the pro teams switching cite improved grip.

Of course, this is on the new, wider rims... the aerodynamics, for example, are definitely better than they would be with an old-school 19mm rim and a 25mm tire.

*Giro Tech: Rise of the 25mm tire*


Excerpt from the article:

_Here at the Giro, the 23mm is in decline, replaced by its slightly fatter cousin, the 25mm. Many of the teams already recognized for more progressive technological mindsets have begun using fatter 25mm tires for regular road stages – no cobbles or gravel in sight, just smooth(ish) Italian tarmac.__These teams are also among those using the latest generation of wide rims available from companies like Zipp, Hed, Shimano and Bontrager.

The swap is usually spurred by mechanics and sponsor liaisons; it falls on their shoulders to convince their riders that a wider tire is beneficial. Among those with a penchant for tradition, it’s still a hard sell, and even within teams that have largely made the change there are still a few riders on skinnier tires.

“We use the wide tires on the wide wheels, it’s a better fit and more comfortable, “ explained Rabobank mechanic Joost Hoetelmans before Friday’s stage.
At the end of the day, each rider has the final say in what can be a very personal decision. Tires represent, after all, the thin line between themselves and the tarmac.

To convince their riders, mechanics are touting the lower rolling resistance often associated with sizing up, as written about extensively by VeloNews.com’s own Lennard Zinn, as well as touting comfort over hours in the saddle. Cornering grip comes up as well – an important factor here at the Giro, which never seems to go in a straight line for long.

“You get more grip, more comfort; the guys like it,” Hoetelmans continued. “We never put more than 8 bar (116psi) in them, except for some of the Spanish guys, they really love high pressure. I don’t know why, but they do. So to make them happy I have to put more in. We run about 1 bar (15 psi) lower in the wider tires than in 23c tires.”

Rim manufacturers have begun to recommend the wider tires as well, as their own rims have widened 2-5mm in the last two years. Before, a 25mm tire dwarfed narrow 19 or 21mm rim beds, have in negative affect on aerodynamics and providing a less reassuring gluing surface – now, with many of the latest rims measuring 24mm or wider, a 25 fits the rim profile nicely. Though a 23 will usually test faster in the wind tunnel, the difference between 23 and 25 on a wide rim is usually quite small –apparently small enough to be outweighed by the other benefits._


----------

