Rubble

I'm two months into this and have numerous 20+ mile rides in. I know that's nothing for many of you but I'm working on it. Did 22 last night that was 1 mph faster than 2 nights before. Baby steps.

Changed out to clipless pedals and I'm glad I did. Because I'm one of those curious types, I'm wondering what, if any, gains I'd get by changing from 32 to 28 tires. I understand they may feel harder underneath but will the speed or rolling resistance be worth it?

Carbonfiberboy 

It's not so much the width of the tire as the weight and composition of the carcass. Depending on what tires you have on there now, you'd probably notice a difference going to say, Michelin PRO4 Service Course or Conti 4000 S II, both in 25mm.

TGT1

It's all about tire construction and tread contact patch not necessarily the width.

I switch back and forth between 42mm Conti Crossrides and a 22-24mm Force/attack race set and there's no detectable difference in rolling resistance. Inertia and crosswind sensitivity, definite difference.

The 32mm Conti Crossrace were a drag on pavement even though they are a very light high thread count supple tire.

FrenchFit 

One of my fast bikes is running 20s, plenty comfortable for this big guy. For a road bike, 25s seem to be a sweet spot, anything bigger feels sluggish. On a 26" rim I like fat tire but I'm going for plush ride with a load, not for speed or distance.

Quality tires are worth the money.

ModeratedUser150120149

When I changed tires I discovered labeled tire size is more like an inventory number than an accurate size. Same brand and model tire. Labels say one is 28 and the other 32. In fact, both are same size.

Frankly, I think for Most of us there are enough factors at work on our rides that any difference caused by a few millimeters difference in tire size gets lost in the mix.

badger1

As others have said, width in and of itself is not the main factor. What matters is tire construction/quality, and correct inflation. As between 25, 28, and 32 on a 700c wheel, here are my observations derived from the past six years (including this year), riding a 2010 Sirrus Comp.

Stock tire: Specialized All Conditions 28. Reasonably light, but not at all supple; ok for rolling resistance. Harsh at correct pressure. Replaced with

Continental GP4000s 25s. Much lighter; very supple; very low rolling resistance -- noticeably so. Not too harsh at all at correct (slightly higher than above) pressure. Replaced with

Current tires, Specialized Roubaix Pro 30/32s. Slightly heavier than the Contis, but I don't notice. Very supple; very low rolling resistance. Every bit as 'fast' as the Contis at their correct lower pressure, and very, very comfortable. The latter is the result of their construction and lower required air pressure for a given load.

As far as I'm concerned, I've experienced only gains by going from very good 25s to very good 32s. Both are vastly superior to the 28s that came with the bike. If I were racing/cared about such things, I might be concerned with increased aerodynamic resistance with 32s, but I don't race so I'm not concerned about such things.

JohnJ80

Presuming tire inflation is correct and similar tire quality/construction, I'd think that the OP would see a performance gain going from 32 to 28 and not much different in comfort. One of my bikes has 28c on it and the other has 25c and still don't see too much comfort difference between those either, but it is noticeable. 25 to 23c there is a big difference. 23 to 22 or 21c is a huge difference. It's not a linear relationship; comfort vs tire volume.

J.

osco53

On my LWB recumbent I started with a 28, moved to a 32.

I got a far more comfortable ride with no noticeable loss in speed or any other performance variable.
The 28 tire had a max psi of 125, I ran it at 100
The 32 tire has a max psi of 80, I run this tire at 75 psi.....

More width and lower psi did not hinder me in the least..

MinnMan

Also depends on tire tread - slicks vs. knobby or intermediate amounts of tread.

Heavily treaded tires will slow you down, and if you are riding on paved trails and roads, you need a minimum amount of tread.

Nothing is a panacea, but sure, try 28s next time you need to swap tires and see how they feel.

McBTC

As I understand it, narrower and lighter tires will always be faster because gains from lower drag coefficients and tire weights will outweigh any greater efficiency due to the decreased rolling resistance of fatter and heavier tires. So, going to --e.g., 25s would be faster than 32s or 28s.

badger1

On a velodrome surface, sure; otherwise, incorrect as stated.

If that were true as an absolute statement, without qualifying variables, elite/pros would not be now as often as not be using 25s rather than 23s or 20s as formerly, and would not be using 27/28s, and even 30s, in races such as Paris Roubaix rather than 25s. And elite/pros do ride at actual racing speeds, where aero drag coefficients and weight (climbing) matter, unlike virtually everyone here and almost certainly unlike the OP.

wphamilton

I saw a marked difference between 32 to 28 tires. Thick sided heavy 32's (low end Kenda's), more supple 28's. Had I laid out 3 or 4 times as much for a higher quality 700c x 32 tire it might have been a different story.

My perspective, and it's basically personal preference, is that unless there's a specific reason to have 700x32 tires such as the types of surfaces I'd be riding on, I will generally prefer the 28.

MinnMan

Yeah - there are tons of threads about this on BF - the consensus is moving in the direction of 25s being nearly ideal for many road conditions - although the wider rim widths coming in to vogue can make 23s about the same as 25s.

But back to the OP's original point - he's riding a nice hybrid for which 23s or 25s are probably too thin. As far as I can see, the OEM tire is something called a Specialized Nimbus, which looks to be a low-tread hybrid tire. He's been riding for a couple of months and enjoying it and thinking of small gains in performance. In his place, I would maybe wear out the OEM tires and then replace them with 28s - something like Conti Gatorskins or Schwalbe Marathon Supremes. Or I might switch now and keep the OEM tires as backups. To be sure, swapping tires is the least expensive change that will give him a little performance boost. It's much more sensible than pretending that componentry makes a big difference.

John E

As was noted earlier, make sure you are comparing tires of like actual width, not merely callout width. Since Continentals run small, I use 700Cx28s on my Bianchi, which cannot accommodate true 700Cx28s, such as Specialized Armadillos.

Also, beware of rim width vs. tire width compatibility limitations, as outlined in Sheldon Brown's admittedly conservative table. Use actual size instead of callout size when using the table.

RR3

The only high quality 32mm road tire is the Compass Extra Legere and on rough chip seal, I seriously doubt any 25mm tire rides as fast or as comfortably. I also ride Vittoria CX iii EVO in 25 mm, Conti GP4000si in 25 and 28, and VeloFlex 25mm Masters and on the rare smooth road, they are fast.

All of these tires are faster than virtually all less expensive tires and can be a revelation.

NVanHiker

After decades of experimenting, I've settled on 28's for commuting and touring. Anything smaller and you worry about pavement seams, while the 28's give you peace of mind. You can pump 'em up hard and go fast, and they're good on any surface, even trails. A few months ago I switched from Conti Gatorskins to the latest incarnation of Specialized All Condition Armadillos and I'm thrilled. They're the 60tpi version, rugged, roll nice, and I wouldn't be surprised if they never flat.

Mandeville

Same brand of tire and tread at optimal psi offers less rolling resistance at the larger size. Also more comfortable riding and stops better. Counter to that is less aero.

Personally I've found that for climbing on paved roads that whether I'm riding a MTB with road tires 2 inch are faster than 1.5 inch and on road bikes 28 are faster than 25.

As far as handling the larger the tire generally speaking the less nimble the bike is and it doesn't accelerate as well--as in you see traffic light controlled intersection is going to change and you will have to stop unless you immediately go 100 percent to speed up to safely get through the light before it changes. YMMV.

StanSeven

Lots of good information posted. I really can't add anything except rolling resistence is likely not perceptable from riding. A few watts difference is a scientific measurement. What likely is felt between tires is suppleness.

AverageJoe2.0

If you are sticking with a different width of the same tire, I'd say the minimal gain wouldn't be worth it, or possibly even noticeable. If you are displeased with your current tires and looking to upgrade to something higher quality, the better construction and suppleness of the new 28mm tires may well offset any loss in ride quality from your old 32s while giving you a boost in performance. Don't expect miracles though, you will probably get a bit faster spin up and notice that your bike is a little quicker on climbs. On the flats at a steady speed, you aren't going to notice much.

irwin7638

Look through the Bicycle Quarterly blog Off the Beaten Path. A lot of testing has been done concerning that question and they seem to believe that the larger tire (within a specific range) will be more efficient. I have noticed that going from 23 -25 on my road bike made it much easier and possibly faster over the irregular pavements that have been chipsealed. These days I use 32mm on my Hillborne for charity rides and find myself scrubbing off speed to avoid people when riding in groups. The softer, wider tires will absorb and rollover the irregularities more effectively than the narrower harder tires. But judge for yourself.

Marc

GravelMN

I've got 32mm Bontrager AW3s on my touring mutt. A couple years ago it had 28mm Specialized All Condition Armadillo Elites. The AW3s, though larger, are just as fast (maybe faster) and a lot more comfortable.