bccycleguy

Is there any advantage to using 25C tires over 23C tires on rough surfaced roads where you can run the 25C's at say 10 - 15 psi lower pressure? Would this give you better grip on corners on chip-sealed roads to say nothing about a bit more comfort?

I know from touring experience that running larger tires at lower pressures is easier on the rear end when the road surface in poor condition, or has lots of cracks, i.e. the Icefields Parkway in the Canadian Rockies. But that was with 32+ tires on a loaded touring rig.

What about riding on cobblestone streets in Europe, what is the best sized tires for dealing with pavé? I've read that most teams in the Paris-Roubaix try to fit the largest tires on their bike that will fit, which on most performance road bikes is not more than 25C's.

Is it worthwhile having a set of 25C tires for those situations?

Fat Boy

I've thought about running a 25c rear across the board. It has a slightly lower rolling resistance and a slightly higher aero drag. Since the air at the rear tires is junk anyway, what can it hurt? The weight difference is nothing, and it's gotta ride better. Since it's more rubber on the road, it probably corners and wears better (rarely do you get that combo).

I don't think it's a coincidence that the top Continental racing tire pair is a 22/24 combo. They seem to have found an advantage in staggered sizes.

As far as cobblestone streets go, in the Paris-Roubaix race, I believe most people run 27c tires or wider to run lower pressures and reduce the chance of pinch flats and to try to keep their teeth in their heads.

jfmckenna

I like 25's and yes you can tell the difference. I usually pump mine to about 95psi.

linux_author

some 23s ride like 25s, but i stick with 25s down here, as a quick detour off the road and there's nothing but thin vegetation and sand - i don't feel like getting thrown off the bike

Grasschopper

I ran 25c P2Rs at the Austin Livestrong ride this past year rather than the 23c in previous years and it made a ton of difference. If you have a lot of chipseal in your riding go for the 25c for sure.

thirdin77

I can't run my 25's at a lower pressure than my previous 23's because a lower pressure made the wheels feel like the rim was contacting the ground through more jarring bumps so I run the 700x25's at 110psi, same as my 700x23's, but same pressure in a wider tire still makes for a more flexible tire, more compliant ride. With my 23's I would often have to get out of saddle to absorb road shock but with the 25's I get out of saddle much less often.

I've never been to Paris or the cobbles but the thought of doing it on 23's makes me not want to .

Surferbruce

25's will definitely handle rougher roads better. you can run a little less pressure, say 90-95 psi or so, and it'll make a nice difference. as for cobbles, many riders in the PR run 27mm's, but know that cobbles in Paris will likely be much better (smoother and more even) than the cobbles you'll find in the Arenberg for instance.
a little wider tire is exactly the tool for the job.