DougG

I've been trying to convince certain of my friends of this for years, so nice to see this presentation on the issue. I know for sure that they sure are more comfortable to ride on!

John E

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.

BobbyG

I went from 23s to 32s on my old roadbike mainly for comfort. While I feel like I may have lost .5mph average speed, comfort, stability and cornering are all better (cornering is MUCH better).

DrIsotope

Distance: 101.2 miles
Time elapsed: 5 hours 16 minutes
Avg. Speed: 19.2mph

Tires: Maxxis Re-Fuse 700x32 (mount to 34.5 wide on my wheels)

Would I have been faster on a narrower tire? Not on these roads.

Barrettscv 

I'm running the Vittoria Corsa in the 700x28 size, and it's the fastest rolling tire in my stable. It's an improvement over the 700x25 Vittoria Corsa CX or the 700x23 Vittoria Rubino III or any other 700x23 tire on typical pavement in my area. Roads here are not perfectly maintained. I usually can reduce the air pressure in the 700x28 tire by 15-20 psi, compared to a 700x25. Yet the 700x28 tire rolls with less resistance on the rural pavement in my area.

Taking the point one step further, The 700x32 tires in my stable are as smooth rolling and require the same or less effort at a 17 mph pace as the racing tires I use in the 700x25 size. Pace matters, since the aerodynamic drag of the larger tire becomes a factor as the speed increases. At approximately 25mph, aerodynamics become equally significant to rolling fiction.

Much of the rolling resistance is contributed to suspension losses. These suspension losses increase with higher pressures. The larger tire, at a reduced pressure, requires less energy since the rider is not absorbing smaller impacts from road imperfections. The tire must be very supple and feature an advanced rubber compound that keeps rolling resistance low. A stiff tire with a hard rubber compound is going to have a high rolling resistance regardless of size.

Even more interesting is this test that compares the 23, 25 and 28 size Continental GP 4000S II, see;

https://www.bicyclerollingresistance....0s-ii-23-25-28
.

Terex

I agree with the road type. If I was on fresh, smooth asphalt, 23's with latex tubes would be my choice, but that is hardly ever the case. I've bumped up the tires on all of my road bikes to biggest width they will handle, and my new mtn bike has 27.5 dia, 3" width tires - which is awesome, but a different deal altogether.

donheff

I have been riding 700x32s for years and remember reading an engineering analysis about them posted here. It touted the good rolling resistance based on rolling profile and recommended much lower inflation pressure than typically recommended.

OldsCOOL

I ride smooth roads so the wider/softer tire trend isnt for me. I can feel the difference on hills, which are many here.

hatrack71

I generally ride the narrowest tire I can on my road bikes. Usually 23 but maybe 25s sometimes. It depends on whether it will fit. I have some very tight race frames. It does demand you know how to pick a better line as they certainly flat easier. And that you know how to use your upper body as suspension by relaxing it and not locking yourself up. Technique is everything!!!! I am faster, climb better and expend less energy on narrower tires, no doubt about it...... known this for decades from riding a ton and racing USCF. Nobody in the Cat.2/3 ran wider tires....at least to my recollection. In fact most ran the most narrow tubulars you could get. Vittorias in my case. But there are downsides..you can't go everywhere. I certainly would rather have 28 or 32 on rougher roads or single track or for commuting/touring. But that's why I have mountain bikes with skinny tires and drops too. The more precise tracking is what I like about road bikes and adding wider tires deadens the lively feel of a road bike that I like.. YMMV.


...That all being said, I should try wider 700c tires again. I do notice the local roads getting rougher every year as well as my bones getting older. :^) I do have a Trek 520 with 32s. That's a special case though as it is set up for touring. I can't see running 23/25 with a full load.

NYMXer

Let's see if I can explain my findings in a way that make sense..... I am not sure about any mathematical advantage skinny or wider tires may have over each other but from a rider comfort point of view, I have found 28's work great for me (over 23's) with no loss in my Strava times but a huge gain in my riding comfort. I believe that the gains in riding comfort decrease rider fatigue and hence, increases rider performance while the tire performance gains (or losses) might be almost nonexistent.
So, if rolling speed is almost equal but the rider is more comfortable (and confident), faster times are certainly possible.

DougG

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!

NYMXer

Most of our roads here in the Catskills are chipped and any paved roads have too much traffic for my liking so, I can't miss what I never get.
I have found that riding the fog line helps decrease resistance. Paved roads must be almost as nice as a tailwind,

Wilfred Laurier

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.

Wilfred Laurier

When I switched from 28mm tires to 38 mm tires I was amazed at how I could suddenly float over chipseal and cracked asphalt. The rough road to my camp in North Western Ontario was fun when I was a teenager on a racing bike, then less fun as an overweight young adult trying to recapture teenage speed, then fun again as I matured and started using high-quality wider tires. If Strava had existed thirty years ago, I would love to compare my middle-aged performance to my teenage performance.

tarwheel 

It depends. On rougher pavement, wider tires are possibly faster. On smooth roads with a lot of hills, it's doubtful. Wider tires are almost always heavier than narrower ones, and the weight will make a difference if you're doing a lot of climbing.

BlazingPedals

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.

Carbonfiberboy 

Wider tires at the same pressure have lower resistance. Wider tires at the same drop have more resistance, both internal and aerodynamic. More importantly, there are frequently differences in casing between various tires, even from the same manufacturer, which can make a considerable difference in resistance. For good discussions of this, see:
Continental Grand Prix 4000S II 23 25 28 mm Comparison
Schwalbe Marathon 32, 37, 40, 47 Comparison

az_cyclist

I switched from 23mm to 25mm a year ago. I am not fast enough (last Saturdays club ride was 66.6 miles and I ave 17.9 mph rolling) to be concerned about speed, but I do like the ride, especially for long distance rides. I feel that Michelin Pro4 Endurance have a softer ride than Continental 4000, slightly. I may try 28mm at some point. that is as wide a tire as my road bikes will take.

Wilfred Laurier

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.

1Mule

Depends on the road surface, but anymore I ride as wide as the bike will allow for comfort, I feel better in the later hours of long rides with them.

rando_couche

Where do you find roads like that?

fietsbob

Expensive made casing wider tires * may be offering lower rolling resistance , faster is still about Your Work Effort Output.

*If you believe the Roll down tests in VBQ, which results in the Compass tires they sell being the best.

fietsbob

I came across an exceptionally smooth road while on tour in Northern Ireland ..

when I commented on how nice it was The local said they did that for its use as Part of a Motorcycle Race Circuit.

Shimagnolo

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

az_cyclist

The Michelins do appear to be wider than the Conti's, but further in the review it states the width at 25mm