Originally Posted by
achoo
At the OPs weight, 25s or even 28s would be a much better tire choice.
I'm 200+ and the only time I use 23s is on my front tire for actual races on smooth pavement - I always have a 25 on my rear wheel.
I'm 225 and I've ridden Michelin 20's until just a few weeks ago when I bought 23's. I think 23's are fine for my weight on our roads, but in comparison I think 25's would be fine too. I just bought new tires so I'm not going to buy new some new 25's just to find out. I have 28's on my hybrid bike and I think they would be too big for a fast road bike. I thought I recalled that 28's were acceptable for my narrow road bike rims but I can't imagine that they wouldn't look a bit funny.