I have read a lot of different sites that claim the comfort of a bike is more determined by tires, wheels and seat more than frame material. One main area of discussion is tire size. For those of you that hve ridden both:
Is a 25c more comfortable than a 23c?
Will a 25c fit on most bikes, (wheel width?)
Any downside to running a 25c?
I do not know much about this stuff. I bought a Cannondale Caad 9.5 and it beat the everloving crap out of me on anything longer than 45 miles. I got rid of it after a week. Could the tire change have made a big difference?
Yes, a 25 would give a slightly better ride quality than a 23 and a 28 would be slightly better again. In my experience, the difference between 23 and 25 (or 25 and 28) is less than that between 20 and 23. You can fit a 25 in most modern frames and brakes but a 28 is too wide or too tall for many. The main downside of a 25 would be that it’s slightly heavier than a 23. In addition, there is less selection in 25 than 23.
The other thing you might consider is the amount of air. Wider tires have lower maximum inflation rates so they help you avoid the overinflation many seem to think will make their bike faster. I weigh 183 and get along fine with 100 psi, sometimes 105 in the back. I find almost any bike seems harsh with 120 or more.
As far as comfort is concerned, I think that with the right pressure, you can have a 23c tire provide enough cush for most people and most conditions. There are some very nice tires now being offered in wider widths. I’ve been a huge fan of the Vittoria Pave tires which are a 24mm width. They also provide some additional puncture resistance in the form of additional strands of kevlar per strands of cotton casing. Vittoria is now offering their superlight Diamante Pro Light tires in 25mm width as well as the legendary Open Corse Evo CX. One nice perk is a 25mm tire should offer less rolling resistance than its equipvalent 23mm version.
The 25c tires should fit most frames, but the need for accurate wheel alignment, dish, and trueness takes on greater importance.
The only downside to the 25mm tire is the slight increase in weight for a given quality of tire, but with the premium tires now being offered in the larger volume widths, there are only a few grams that seperate teh very best tires out there.
I made the switch from 23c to 25c (for training) this year and I’ll never go back. Brett Hahn, from Conti, told me to give 25s a try and I figured I should listen to him because he ought to know a thing or two about tires. The benefits far outweigh the downside. They’re tougher, corner well and are slightly more comfortable. I’ve been riding the same pair of Conti Gatorskin 25s since March and have had zero flats–no joke.