Question about tire size...

If you pop on a 25 or 28 road tire for fit you can storm the dirt and not be a victim of the excess drag of cross tires. The bike handling skills can get sharpend by find braking and traction with road tires in the dirt too.

wanderswithin said:

Hi. I need some info. My boyfriend wants to put cyclocross tires on his road bike because of all the nasty dirt roads in our area. The current tires are 700x23c. Is there a way for us to figure out how much bigger we can go without the old trial and error of buying and returning? I want to surprise him, but I don't want him to get all excited and then be heartbroken when they don't fit. Any suggestions would be greatly appreciated. Thanks!! -A.D.

With regards to fit, since that seems like the question you were asking (and a very valid one given that many of today's frames oriented toward racing will barely fit anything wider than 23c)... you can get a good sense of whether say a 28c will fit by looking at the fork and chain/seat stay areas adjacent to the current 23c tire. If you see a 1/4" or more of light, good, you'll probably be OK with up to ~28c. I'm not totally sure if you could go wider, maybe someone has a link to typical tire widths by size? Of course the best thing to do would be take it to a bike shop that stocks wider 700x tires and get their recommendation.