Tyre/Tubular compatability

EJMtreefrog

I have a Cervelo P3C TT bike. I currently run on 23c tubulars.
I know that some older TT bikes do not have the tolerances to take 25c tyres.
Is this the case for the P3C
Is there any advantage to using 25c's?
Thank you

iron-clover

I don't think you would notice much difference going up to 25C tubs from 23c tbh. I'm currently riding on 21C Vittoria corsas, which are admittedly completely naff at cornering unless you put them down to very low pressures which isn't really what tubs are famed for.

However, I've also ridden the 22c conti sprinters which if anything come up a little wider, and were brilliant to ride even over gravel at 130-140psi, and were like riding on rails. I will be getting some for next season for sure, probably the best vfm tub out there.

I can't see how you would get any better performance from a 25c tub compared to a good 23c version, and especially being on a TT rig you probably won't be cornering as much as on a road bike so not much of an issue. Also unless you have wide wheels, the 25c tyres will increase your frontal cross section a little (although in the real world the difference is negligible).

rafletcher

If exactly sized, 25's have 20% more volume than 23's, so give a somewhat less harsh ride. Also at the same pressure and for the same design of tyre, 25's have a lower rolling resistance than 23's. Of course on the same basis 25's are heavier than 23's. But tyre weight is small anyway, and the weight difference overall would pale into insignificance against rider and bike weight.

iron-clover

Just bear in mind that tubs are very different to clinchers with the advice that will be given.

If we were talking clinchers, I would say go for it if you have the clearance, but I find 22c conti sprinter tubs ride better than my 25c (actually come closer to 28mm) michelin pro4 endurance clinchers..

EJMtreefrog

Thanks for this advice, it looks like I will get a set od 22's for next season