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Are wider road bike tires faster?

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Are wider road bike tires faster?

Old 11-01-16, 10:53 AM
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Originally Posted by az_cyclist View Post
The Michelins do appear to be wider than the Conti's, but further in the review it states the width at 25mm
I see "Measured Width 28 mm" in that review.
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Old 11-01-16, 11:36 AM
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Originally Posted by Shimagnolo View Post
I see "Measured Width 28 mm" in that review.
I saw that too. I had another rider ask me if I was running 28's. At any rate they did feel like they had a softer ride than Conti 4000's. I may watch for Conti 4000s to go on sale in 700x28mm, and compare to the Michelin Pro4 Endurance 25mm
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Old 11-01-16, 02:06 PM
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Fewer flats. Nobody mentioned fewer flats with lower tire pressure.
So: Much more comfort, similar resistance (w/supple casing at my low speeds), and fewer flats == big win for my riding preferences.
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Old 11-01-16, 04:34 PM
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Originally Posted by John E View Post
The whole narrow tire fad got overdone. Optimal efficiency evidently comes with about a 15% deflection under load, which, for many riders, would make 25 or even 28mm tires a better choice than something skinnier.
I've read this before, but don't really understand what it means - and how would you measure it? Is there some way to measure it when you look at the contact patch on the road or, say, the part of the tire that is clean after wearing off the dirt from a dirty tire?

Originally Posted by DougG View Post
It is amazing what a difference there is between different types of paved road surfaces. I can ride for miles on a chip-seal road not realizing how much extra effort there is until I turn onto a freshly-paved asphalt road and it feels like a turbo just kicked in!
I can see a ~1+ mph increase in speed when going from chip to smooth pavement. I can feel it too.

Originally Posted by Shimagnolo View Post
If you are riding a Michelin Pro4 Endurance in "25mm", then you already are on a 28mm tire.
See: Michelin Pro 4 Endurance v2 Rolling Resistance Review
Not a PR4 Endurance, but my 23 mm Michelin PR4 Service Course measure a little narrower than a comparable Continental Grand Prix 4000s. The PR4's measure about 23-24 on my Velocity A23 rims vs a healthy 25 for the GPs. For some reason i still like the PR4s better in general.
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Old 11-01-16, 04:53 PM
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Now then. What do the racers use? Tour de France er al. Distance stuff, not all silky smooth roads.
Betcha they ride skinny, and the pressures will be bloody high. A tyre that absorbes bumps absorbs energy.
I had a mountain bike for years with road tyres, 1.5 X 26, was it? Was glad to get rid o` the 1.75 knobblies and put on slicks. It was a hard ride, but faster. Pumped up to about 60psi. Many punctures; many walks home.
Along came the road bike wi 700 X 25 fitted, and the requisite pressure (as much as I can comfortably put in with a hand pump) and they were more comfortable. No puncture in 6 years riding over some country roads until I got a Gator fitted (back) and hit a pothole . . . I rode it home.
Wouldn`t fancy underinflated road tyres, No siree . . . . They`d pick up everything!
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Old 11-01-16, 05:15 PM
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Originally Posted by peterws View Post
Now then. What do the racers use? Tour de France er al. Distance stuff, not all silky smooth roads.
Betcha they ride skinny, and the pressures will be bloody high. A tyre that absorbes bumps absorbs energy.
A tire that is shaking the rider, is stealing energy from the crank to do the shaking.

Scroll down past the aero stuff, and begin reading at Part 4A: https://silca.cc/blogs/journal

Last edited by Shimagnolo; 11-01-16 at 05:38 PM.
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Old 11-01-16, 05:26 PM
  #32  
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Originally Posted by Wilfred Laurier View Post
In the (internal) rolling resistance chart for the Contis, it shows that you would have to go to a much lower pressure to have more rolling resistance with the wider tires. The same can be said about the Schwalbe 32mm vs. wider sizes, which are pretty tightly clustered.
Or to be specific, the 28C at 80 psi had the same resistance as the 25C at 100 psi or the 23C at 120 psi. (within 0.2 watts)
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Old 11-01-16, 05:35 PM
  #33  
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Originally Posted by BlazingPedals View Post
I've noticed that too; but I hesitate to do it much because there's also less traction there. It can be like ice if you hit a wet spot.
I remember when Avocet first came out with their narrow slick tires. Pete Penseyres did a test of them by riding his bicycle up a hill in the rain and staying on the painted fog line. Pete stated that he could NOT get the rear tire to break traction. I guess the rubber compound makes a difference as to whether a tire will slip on painted road markings or not.

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Old 11-01-16, 05:41 PM
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Originally Posted by peterws View Post
Now then. What do the racers use? Tour de France er al. Distance stuff, not all silky smooth roads.
Betcha they ride skinny, and the pressures will be bloody high. A tyre that absorbes bumps absorbs energy.
I had a mountain bike for years with road tyres, 1.5 X 26, was it? Was glad to get rid o` the 1.75 knobblies and put on slicks. It was a hard ride, but faster. Pumped up to about 60psi. Many punctures; many walks home.
Along came the road bike wi 700 X 25 fitted, and the requisite pressure (as much as I can comfortably put in with a hand pump) and they were more comfortable. No puncture in 6 years riding over some country roads until I got a Gator fitted (back) and hit a pothole . . . I rode it home.
Wouldn`t fancy underinflated road tyres, No siree . . . . They`d pick up everything!
A quick google search, tour de france tire size pressure indicates that 25c tires are common, and pressures around 7 to 8 bar, 102 to 116, are typical. (For those lightweight riders, that's quite high pressure for a 25c. For local group type rides, a lightweight rider could easily have 85-90 front, and 100 rear.)

Examples:
From 2014
From 2016


It takes energy to flex the tire, but it also takes energy to jiggle and bounce the rider from the vibrations. That's the theory of letting the tire absorb the chip-seal rough roads. And the thin sidewalls on fast tires can flex without using much energy.

Last edited by rm -rf; 11-01-16 at 05:48 PM.
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Old 11-01-16, 08:58 PM
  #35  
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Originally Posted by rm -rf View Post
A quick google search, tour de france tire size pressure indicates that 25c tires are common, and pressures around 7 to 8 bar, 102 to 116, are typical. (For those lightweight riders, that's quite high pressure for a 25c. For local group type rides, a lightweight rider could easily have 85-90 front, and 100 rear.)

Examples:
From 2014
From 2016


It takes energy to flex the tire, but it also takes energy to jiggle and bounce the rider from the vibrations. That's the theory of letting the tire absorb the chip-seal rough roads. And the thin sidewalls on fast tires can flex without using much energy.
Those are very interesting links to pro race equipment. One thing to point out there, from the standpoint of "are wider tires faster" is that wider rims are faster in typical race conditions with quartering winds. Fast carbon rims are now 25mm and wider so they can get a better wing section and reduce aero resistance. So they have to run wider tubulars to go with the wider rims. I doubt it has anything to do with tire width per se. Tires have to be perfectly fit to the rim to get the aero advantage from the rim. There's a good discussion of all this here:
THE RIGHT TYRE WIDTH ON THE RIGHT RIM WIDTH - Engineerstalk : Engineerstalk

The tire pressures in the first link do not refer to specific tire widths. For TTs, where comfort is not an issue, they run as much pressure as they dare in their tubbies - because it's faster. I mean 15 bar on a road stage? for a TDF rider? what could he have weighed, 180?
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Old 11-01-16, 09:08 PM
  #36  
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I hear that the pros have been going to wider tires lately, especially on the cobbles. That is interesting although they don't ride tires anywhere as wide as I do. I'm on my second set of 38 mm Vittoria Voyager Hypers (but they were called Randonneur Hypers when I bought the first set). At the speeds the pros ride they would be death by aerodynamic drag but they are fine under 20 mph and they roll very efficiently. Yes, the wider tire does absorb bumps very well if you drop the pressure a bit to keep your speed up on rough roads and you have a lot of control over that too because if you max out the pressure you can fly on smooth roads. RAGBRAI is the high point of my cycling year and with mile after mile of road cracks and other hazards to deal with there isn't a day that goes by that I am not glad that I was on 38's. There has been an optional gravel loop the last two years, need I say more? If you are racing then a 28 might be as wide as you could consider but for me those are the bare minimum!
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Old 11-02-16, 05:30 AM
  #37  
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Originally Posted by Wilfred Laurier View Post
A good quality, lightweight, and supple wide tire may have lower 'rolling resistance' and less suspension losses, but are generally heavier and can actually result in higher aerodynamic resistance (the reason why triathletes used to use 18mm wide 650c tires).
If you are fit and tough enough to take the pounding, a narrower (~25 mm) tire at high pressure is probably the best choice for maximum performance for most riders. As your desire for all-out speed decreases and/or your need for comfort increases and/or the road gets rougher, wider tires are more appropriate.

I think the ideal tire/tire size is different for every individual and their road conditions. I generally like to use between 32 and 38mm tires.
I currently ride with 28mm but am definitely considering going to a 32mm with some kind of tread next spring. After a couple of wipe outs just within the last couple of weeks on wet surfaces, I definitely need something with a little more traction and comfort as well.




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Old 11-04-16, 04:36 PM
  #38  
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I don't know if they're faster but I haven't found they're any slower. On long rides, I find the comfort of wider tyres saves energy and makes me faster at the end of the ride compared to tooth rattling skinny tyres....
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Old 11-04-16, 05:00 PM
  #39  
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Originally Posted by IndianaRecRider View Post
I currently ride with 28mm but am definitely considering going to a 32mm with some kind of tread next spring. After a couple of wipe outs just within the last couple of weeks on wet surfaces, I definitely need something with a little more traction and comfort as well.

Traction on hard surfaced wet roads is more about rubber composition than anything else.
Tires intended to optimize long wear use a harder rubber, with the downside of poor wet traction.
Tires intended to optimize traction use a softer rubber, with the downside of shorter tire life.

On wet roads I've found Schwalbe One and Schwalbe Marathon Supremes to be excellent;
As opposed to Gatorskins that break loose w/o warning.
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Old 11-04-16, 06:29 PM
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Speed is not the only desireable factor in tire size selection. Handling is an important factor, to me, anyway. Anything over 24mm just feels bulky and unresponsive to me.
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Old 11-04-16, 09:28 PM
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Originally Posted by 1989Pre View Post
..... Anything over 24mm just feels bulky and unresponsive to me.
I can certainly appreciate that at some stage installing wider tires on narrow rims will worsen handling (especially if pressures are reduced).

Is it possible that that handling reflects more than tire width, as it is not clear to me why a wider tire on a wider rim should handle markedly worse than a narrower tire on a narrower rim

I find it a challenge to sort everything out - but my impression is that for any given bike/rider, there is an interplay between several factors, including;
~ rim width
~ tire width (actual on specific rim, not what manufacturer states)
~ tire pressure
~ tire construction

So much to learn - what tire widths should 'N+1' Road bike accommodate in 2017 ? (sounds like a 1st world problem, eh)
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Old 11-05-16, 05:35 AM
  #42  
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Originally Posted by Shimagnolo View Post
Traction on hard surfaced wet roads is more about rubber composition than anything else.
Tires intended to optimize long wear use a harder rubber, with the downside of poor wet traction.
Tires intended to optimize traction use a softer rubber, with the downside of shorter tire life.

On wet roads I've found Schwalbe One and Schwalbe Marathon Supremes to be excellent;
As opposed to Gatorskins that break loose w/o warning.
That's good information to know. Will look for something with softer rubber when the time comes.

Thanks, I appreciate it!!




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Old 11-05-16, 05:53 AM
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Originally Posted by 1989Pre View Post
Handling is an important factor, to me, anyway. Anything over 24mm just feels bulky and unresponsive to me.
We may be the only ones that understand and believe it. I wont have 25's because they are heavier and I can feel it. In a hillclimb or sprint (horizontal hills) you can tell right away.
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Old 11-05-16, 07:22 AM
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The simple laws of physics cannot be set aside. Narrow rock hard tires cause the bike to raise up. That vertical motions sops energy, and makes the bike slower period!!!!

That is why way back when pneumatic tires were invented and replaced the hard rubber strips on bike wheels, bikes suddenly became faster. Hard to argue against this. If narrow rock hard tires were faster, racers would be using hard rubber strips on their wheels instead of inflatable tires.

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Old 11-05-16, 08:20 AM
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Originally Posted by OldsCOOL View Post
We may be the only ones that understand and believe it. I wont have 25's because they are heavier and I can feel it. In a hillclimb or sprint (horizontal hills) you can tell right away.
The basic laws of physics, in this case, adhesion, provide us with the knowledge that when surface contact area is increased, adhesion increases. This means that 25's (and certainly anything above) are harder to propel or turn than 23's, unless the compound is harder. I do not want this on a long ride.
Many times, the nibility of the 23's have allowed me to surgically manouver past, there-by preventing me from hitting, small objects (or recesses or bumps) in the road. 25's (and above) provide added comfort. I can appreciate this.
I am not looking for "comfort" on a training ride, and anyway, my road bike is perfectly comfortable, even without padded bar tape.
There is a reason that we, as kids, eventually left our Sunbeam and Firestone cruisers in the garage and bought Raleigh Sprites or Schwinn Varsities.., and it wasn't just the number of gears.

Last edited by 1989Pre; 11-06-16 at 01:46 AM.
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Old 11-05-16, 12:59 PM
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25c is my preference. I don't really care much about gaining a quarter of a second in speed with narrower tires. All I know is that they are more comfortable to ride than a 23c and my bike won't take a 28c. I do know that I am noticing more and more new bikes being shipped with 25c tires than 23c tires, including tri-bikes.
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Old 11-05-16, 02:46 PM
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My 'Arizona bike' - the one I keep in AZ to ride when I visit - came to me with 22mm front and a (flat) 25mm rear. I had a problem with the little riding that I did out there last visit because the pavement is rough. The asphalt binder just 'goes away' in the desert summer heat, leaving an exposed aggregate pebble surface - at least on US60 from Apache Junction to Florence Juntion (AZ 79). That high pressure 22mm front tire beat the crap out of me. I had changed out the rear 25 for a heavy Vittoria Randonneur II 28mm, but am reconsidering. I'm going back out to AZ this next week, and bring two sets of new tires -- Vittoria Rubino Pro Tech III in both 25 and 28mm widths. We shall see...
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Old 11-05-16, 09:42 PM
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Originally Posted by OldsCOOL View Post
We may be the only ones that understand and believe it. I wont have 25's because they are heavier and I can feel it. In a hillclimb or sprint (horizontal hills) you can tell right away.
I am impressed you are that sensitive. Wonder how much more cycling I need to do to reach such a level?

I am pretty sure I could not tell the difference (I understand about 20 grams each wheel - say 40 grams in total - for Continental 4000Sii).

Although I confess that when I switched from Grand Prix to the 4000Sii I am pretty convinced I liked riding on the latter more than the former - but never did conduct a 'blind test' to try to determine whether this was anything more than the 'placebo' effect!

Like I said - fascinating 1st world challenges.
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Old 11-05-16, 11:47 PM
  #49  
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Originally Posted by 1989Pre View Post
The basic laws of physics, in this case, adhesion, provide us with the knowledge that when surface area is increased, adhesion increases. This means that 25's (and certainly anything above) are harder to propel or turn than 23's, unless the compound is harder. I do not want this on a long ride.
Too bad none of that is true in regards to our application. From the Velonews CRR tests a few years back:

"Tire rolling resistance on the road is caused by (1) internal friction and hysteresis (deformation over time) within the tire’s materials, and (2) on rough roads, small bumps lifting the bike and rider slightly (uphill) on each little impact.

By definition, wider tires will have shorter contact patches and, hence, less tire deflection; if the tire pressure is the same, the area of the contact patch must be the same to support the same load. The shorter the contact patch, the lower the vertical depth of tire deflection; the internal friction and hysteresis within the tire’s materials is lower.

If a wider tire is made of the same materials in the same thickness as a narrower one, it will roll faster, because (1) the internal friction and hysteresis within the tire’s materials will be lower, and (2) because the surface imperfections in the road will be absorbed into the tire more easily (since it has more deflection available), thus lifting the bike and rider slightly less with each little impact."


A wider, heavier (even much heavier) tire would be slower only for the amount of time between standing still and cruising speed. Then, the wider tire would maintain a higher speed for the same wattage output compared to a narrower tire.

My personal favorite from this whole thread is feeling the difference in weight between 23s and 25s. That is simply remarkable BF-ness. Almost unparalleled. The weight difference between a typical 23 and 25 tire... about 20 grams.
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Old 11-06-16, 07:25 AM
  #50  
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Originally Posted by FamilyMan007 View Post
I am impressed you are that sensitive. Wonder how much more cycling I need to do to reach such a level?

I am pretty sure I could not tell the difference (I understand about 20 grams each wheel - say 40 grams in total - for Continental 4000Sii).

Although I confess that when I switched from Grand Prix to the 4000Sii I am pretty convinced I liked riding on the latter more than the former - but never did conduct a 'blind test' to try to determine whether this was anything more than the 'placebo' effect!

Like I said - fascinating 1st world challenges.
Nice sarcasm.
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