# So what makes road bikes so fast?



## kthung

A brief introduction before I get to my question: 
So I am relatively new to cycling (bought a new Trek 7.2 FX hybrid bike last september to ride around my college campus) I rode to my classes basically every day that there wasn't snow on the ground and a few weeks ago I did a 50 mile charity ride and I think I might be hooked. I've begun lusting over road bikes for the past few weeks but I probably won't be able to get one until next summer at the earliest. I just bought a bike less than a year ago and I'm college student (enough said I think). Also I want to start racking up the miles before I take to plunge to make sure this is really something I want to do.

Anyways, on to my question. I know its a combination of several things, but what is the most significant factor makes road bikes faster than hybrid bikes like my Trek FX? I usually do about 25 miles at a time. Now I consider myself relatively fit but according to my bike computer, I only average about 15 mph. Having read the forums I see that people are averaging up to 25-30mph. Going downhill as fast as I can my max speed has only hit 29 mph. So what makes the biggest difference between a road vs hybrid bike? Is it the more aggressive/aerodynamic geometry of a road bike? Is it the weight (my bike is around 28lbs vs. the average entry level road bike is ~20lbs)? Is it the wheels (I know most road bikes have 700x23mm tires where I have much wider 700x35mm tires)? Or is it me? Do I just need to run my ego over with my bike and tell myself I'm not as fast as I think I am?


----------



## Nimitz

biggest thing is the more aero position it puts your body in, usually the better gearing as well, i would say the bike being STIFFER is a HUGE factor...when I stomp the pedals on my road bike it just GOES. (caad9)

weight would be one of the smallest factors...the 23-25mm wheels with higher pressure and less rolling resistance are big too.

Chad


----------



## rangerdavid

i agree with the tire evaluation. the less rubber on the road, the less resistance. same with tread. less tread, less resistance.


----------



## pdh777

Your conclusions are pretty good on the reasons a road bike is faster.
1) Aerodynamics
2) Narrower tires = less pavement friction
3) Gearing is more for speed on most road bikes, more so than a hybrid.

If you do decide on a road bike keep the hybrid for utilitarian duties.

Also - there are very few people with road bikes who go out and average 25 mph or over on a training ride. - the few that do are in the pro peleton. That being said you can expect an increase in your general speed with a road bike.


----------



## kthung

Thanks for the responses guys. The reasons I asked were because I was wondering if I could upgrade just a few components in the mean time to bump up my speed just a little without having to drop a grand on an entirely new bike. I guess wheels would be the way to go since I could always move them to the new bike if I eventually decide to get one. 

Either way I will definitely be keeping my hybrid for getting around to places. No way I would leave my out, locked up somewhere on a college campus. If I'm leaving my house with a road bike, I'm not getting off till its back home safe.


----------



## kthung

Wow! Great writeup Kristy, thank you very much! I have read about pedaling with a higher cadence and you're right, I need more practice spinning smoothly at higher rpms especially when climbing. Right now it's difficult which may partly be due to the fact that I ride a hybrid and dont have cycling shoes and clipless pedals so my feet might slip off the pedals at really high rpms, but I will still practice.


----------



## Hooben

Well first of all, that wasn't Christy's writing. That was Al Lyman from...

http://www.trifuel.com/training/bike/why-fast-pedaling-makes-sense

Good thing we aren't in class or you would be in trouble for plagerism!

Good article, but that doesn't address your hybrid bike. The truth is that you are going to have to invest in a new bike to really see some speed increases. When I jumped from mountain bike to hybrid, I noticed a difference. Then I went from hybrid to aluminum road bike, once again a difference. Finally, I invested in a full carbon racing bike and now can sprint well over any speed that I could ever attain on the flats on any other bike. Go out and test ride, lay away, whatever it takes. Once you go full road bike, you will never regret it. Oh, and keep your hybrid...they are great bikes that are really fun to ride.

The most significant factors are...
Frame Geometry and Chainstay stiffness (provides full transfer of power)


----------



## tihsepa

25-30 MPH?

Right............ Get out and ride. You will find you can keep up. Maybe not for long at first but you can do it. 
5 Years ago I spent two seasons pushing it before getting involved in any groups. I would average about 17 MPH for 2-3 hours straight. Still thought I couldnt keep. Well I was wrong. Get out and ride. You will soon notice that on a 60 mile ride by yourself you wont get passed much, by anyone. 
Riding bikes is fun, dont forget that.


----------



## Dresden

All those things you mentioned make a road bike faster, but if you're averaging 15mph on your hybrid, don't expect to average 25mph just by switching to a road bike. You'd probably gain about 2-3 mph.


----------



## jsedlak

25-30 mph would be nice...

On a good day our group will average 18-19mph at the front, and around 16 at the back. Also don't forget that riding in a group is a lot easier (on your muscles) than riding alone. We could probably go 21-23 all day but then it would feel like work.


----------



## Dr. Nob

kristy19 said:


> hi.
> 
> Thank you for sharing.
> 
> ance has revolutionized cycling in several ways. He�s shown you CAN come back from a serious illness like cancer and return to top {SNIP} and so on



Well where the f did that come from?

The most revolutionary thing that Lance has done was in media manipulation (although he did copy/perfect Riis' technique)

kristy - you could have condensed that down into two paragraphs. It would have been easier to read and would not have breached copy write.


----------



## tom_h

kthung said:


> Thanks for the responses guys. The reasons I asked were because I was wondering if I could upgrade just a few components in the mean time to bump up my speed just a little without having to drop a grand on an entirely new bike. I guess wheels would be the way to go since I could always move them to the new bike if I eventually decide to get one. ...


I don't think that's cost effective, at all. And, I doubt you'll find any dealer willing to sell a new bike minus the wheels. 

I would just ride the hybrid 'as is', rack up more mileage, and start doing some harder 'training rides' to build strength and stamina

If / when it's time to replace the tires, you could select a tire with little or no tread (a "slick"). The energy lost on chunky treads squirming around, is a significant portion of the rolling resistance. Unless you're riding in soft dirt or sand a lot, a slick is quieter/smoother/faster, and a bike tire _won't_ hydroplane in wet weather, no worries there.

You might also be able to install 700-28 in place of 700-35 for slightly less rolling resistance, but for an "around town" bike, the 700-35 is a good choice.

Also consider installing 'old style' toe clips & strips .... cheap, can be ridden with street shoes, holds feet in more optimal position without worries of slipping off under hard pedalling, and will improve your efficiency & power transmission a few percent.


----------



## PBike

*What makes a road bike so fast?*



kthung said:


> A brief introduction before I get to my question:
> So I am relatively new to cycling (bought a new Trek 7.2 FX hybrid bike last september to ride around my college campus) I rode to my classes basically every day that there wasn't snow on the ground and a few weeks ago I did a 50 mile charity ride and I think I might be hooked. I've begun lusting over road bikes for the past few weeks but I probably won't be able to get one until next summer at the earliest. I just bought a bike less than a year ago and I'm college student (enough said I think). Also I want to start racking up the miles before I take to plunge to make sure this is really something I want to do.
> 
> Anyways, on to my question. I know its a combination of several things, but what is the most significant factor makes road bikes faster than hybrid bikes like my Trek FX? I usually do about 25 miles at a time. Now I consider myself relatively fit but according to my bike computer, I only average about 15 mph. Having read the forums I see that people are averaging up to 25-30mph. Going downhill as fast as I can my max speed has only hit 29 mph. So what makes the biggest difference between a road vs hybrid bike? Is it the more aggressive/aerodynamic geometry of a road bike? Is it the weight (my bike is around 28lbs vs. the average entry level road bike is ~20lbs)? Is it the wheels (I know most road bikes have 700x23mm tires where I have much wider 700x35mm tires)? Or is it me? Do I just need to run my ego over with my bike and tell myself I'm not as fast as I think I am?


The rider makes a road bike fast. Oh, that and a healthy amount of exaggeration in posts on the forum. 

Yes a road bike is usually quicker than a hybrid, but it won't make you fast. Actually, riding a heavy ponderous bike would serve to make you faster. You will get a better workout. 

Get a road bike if you want one, you'll enjoy the feel of it and you will, most likely, be faster on it, by a small amount. Don't expect miraculous gains though, but be sure to post claims of averaging 24 MPH over 40 miles. 

If you simply enjoy riding, it doesn't matter what you ride, simply enjoy it. Be careful buying a new bike though, you may not be able to stop at just one. 

Cheers


----------



## jsedlak

tom_h said:


> I don't think that's cost effective, at all. And, I doubt you'll find any dealer willing to sell a new bike minus the wheels.
> 
> I would just ride the hybrid 'as is', rack up more mileage, and start doing some harder 'training rides' to build strength and stamina


+1.

Wheels are so expensive when bought off the bike. They are a major deal when bought on the bike.


----------



## carveitup

I wouldn't upgrade much. My wife has a 7.5 FX for commuting in addition to her road bike. She has considered changing to a closer ratio cog set. The 53/39 crank combined with a 12-25 cog set on her C'dale R1000 works for her so the gearing on the FX is a little too easy. She never uses the granny gear. She also has the stem really low because she likes the more agressive position. Move the spacers from under the stem to the top and/or flip the stem. The only other thing I would suggest is clipless pedals. You could get some with flats on one side for commuting and clipless on the other side.


----------



## crazyc

IMO the cheapest and most significant thing you can change
would be your tires. Go back to the Trek dealer and ask for
a pair of slicks, Bontrager makes a good set for wide rims. I put them on 
an old MTB I used to pull my son around, made a huge difference.


----------



## Mootsie

rangerdavid said:


> i agree with the tire evaluation. the less rubber on the road, the less resistance. same with tread. less tread, less resistance.


This isn't true. Velonews did a tire evaluation about a year ago and the results were that wide tires like 25's and 28's had lower rolling resistance than 23's and 21's. Sounds strange, but they had the data to back it up.


----------



## PJ352

Mootsie said:


> This isn't true. Velonews did a tire evaluation about a year ago and the results were that wide tires like 25's and 28's had lower rolling resistance than 23's and 21's. Sounds strange, but *they had the data to back it up*.


GIGO.


----------



## wim

Mootsie said:


> This isn't true. Velonews did a tire evaluation about a year ago and the results were that wide tires like 25's and 28's had lower rolling resistance than 23's and 21's. Sounds strange, but they had the data to back it up.


Only at identical tire pressures. Since very few people run fat tires at the same pressures than skinny tires, the whole fatter = faster notion is fatally flawed.


----------



## Kerry Irons

*Yabbut*



wim said:


> Only at identical tire pressures. Since very few people run fat tires at the same pressures than skinny tires, the whole fatter = faster notion is fatally flawed.


However, in this case we are talking about coming down from big, fat, thick rubber hybrid tires to regular road tires. While the width alone wouldn't have a large effect, as explained by wim, the change to a real road tire would.


----------



## wim

*I think we agree.*



Kerry Irons said:


> However, in this case we are talking about coming down from big, fat, thick rubber hybrid tires to regular road tires. While the width alone wouldn't have a large effect, as explained by wim, the change to a real road tire would.


Perhaps I'm not understanding what you're saying, but my point was that the claim of wider tires having less rolling resistance than narrower ones is bad science. Narrower tires will always have less rolling resistance than wider tires if these tires are inflated to their proper and thus, different pressures.


----------



## vertex112

This thread in general is getting me very excited. Tomorrow is the day I head out to get my new road bike. And looking at the general consensus, there would be a relatively large increase in speed going from my mountain bike with semi-knobby 2.0inch tires at 40 PSI, to a road bike with 25mm tires and overall huge aerodynamic gains.


----------



## Andrew242

resistance of tire, and weight. Aero will become a factor when you have a faster average speed.

and ive also read that 25 have less resistance in some circumstances. but i will ride 23 anyway.


----------



## Kerry Irons

*Yes, we do*



wim said:


> Perhaps I'm not understanding what you're saying, but my point was that the claim of wider tires having less rolling resistance than narrower ones is bad science. Narrower tires will always have less rolling resistance than wider tires if these tires are inflated to their proper and thus, different pressures.


Well maybe not less resistance, but probably not more. Narrower tire typically means higher pressure, but then you get suspension losses because they transmit more road buzz to the rider as they "bounce" off road surface roughness. As with many things in life, tire width is a tradeoff.

My point was that the OP is not looking at a comparison between "equal" tires of 23, 25, and 28 mm width, but rather that the bike has big tires with thick tread (and probably hard rubber) plus thick and stiff sidewalls. Those tire "features" will contribute a lot of rolling resistance that is not really related to tire width.


----------



## tystevens

As said above, the rider is what makes the bike fast, not the other way around! Don't forget that part of the equation. 

And ditto as to the dubious average speed claims of a lot of people on here -- either a lot of ultrafit hardcore professionals on here, or maybe people just ride a lot faster in other parts of the country than they do here. At least around here in Utah, I average 15 - 17 on most of my solo rides, maybe 17 - 20 on a small group ride, and not that I'm regularly leaving people in the dust, but I'm not getting passed by a lot of people, either. I don't mean to burst your bubble about the speed and efficiency of road bikes, but they won't increase your speed that dramatically. For instance, my road bike was in the shop and I felt like commuting to work. I got out my full supsension mtb w/ 6" travel, 2.4 inch wide knobbies, ect, -- not a real efficient pedaling bike -- and commuted on that for two days. I was right around 14.5 on the mtb, compared to about a 17 mph avg on my road bike for the same commute, roughly same perceived effort.


----------



## Andrew242

the city were i came from i could average 30-32km/h. nowdays in another city were it always are strong winds, i manage on average 27-28km/h. 

when it was almost no wind the other day, i managed 34,5km/h, but it was one day in a million.


----------



## California L33

jsedlak said:


> 25-30 mph would be nice...
> 
> On a good day our group will average 18-19mph at the front, and around 16 at the back. Also don't forget that riding in a group is a lot easier (on your muscles) than riding alone. We could probably go 21-23 all day but then it would feel like work.


Yeah, 30 MPH is a pro on a time trial bike on a flat course on a windless day. 18MPH is a more realistic average for real world pretty fit riders. I think the OP may have been seeing show-offs passing him in a sprint.


----------



## Fredrico

*And just in from the planet Mars:*

Whoa. :7: What was that? A dynamite treatise lifted from a triathlon publication about power delivery at high rpms! As Eddy himself used to say, "If you want to go fast, pedal fast!" I, at retirement age in one month, will attest to this wisdom. Yes, learn how to spin. With clipless shoes of course.

Before long, you're able to power gears like Lance does, 39-23, up the climbs at 95 rpm, panting and puffing, seeing spots, heart pounding like a race horse, but you won't blow up (right away)! You'll just keep going, like the Everready bunny. And when you get old, like me, you'll still be able to spar with the kids once in awhile, because your knees still work, and those slow twitch muscles, the ones that burn oxygen, will be superbly toned from years of spinning. Nobody mentioned that.

What does this have to do with roadbiking and going faster? Well, on a roadbike, you can hunker down on the handlebars and spin your ass off. Not as easy on a hybrid. You're sitting too upright. You pedal like a man walking. Down on the hoods of a drop bar roadbike, you're a svelte cougar, turning that crank around with everything you've got, quads, hamstrings, buttocks, hip flexors, back, shoulders, arms. If you're smooth and can follow that crank around like a well tuned piston engine, you've got power to spare.

Once you get used to the superb efficiency of that positioning, upright hybrid positioning will seem really wimpy. Hey, if you can average 15 mph like that, you'll easily be able to do 18 or better on a roadbike, any roadbike. It's all about positioning (and cadence!).

None of this is to dismiss lighter weight wheels and tires, of course,nor stiffer and therefore more responsive frames, what racing bikes are all about. I bet you could put a pair of 28C's on that hybrid for starters. But sitting up in the wind with your arms spread out will definitely hold back potential speeds possible on a roadbike.


----------

