I have recently had a serious problem with tire/fender clearance during a ride that included unavoidable mud. I ride a Trek 520 and put Continental Top Contact 37 mm tires on it. There is minimal clearance with the fenders which cannot be raised. On dry and rainy rides I've had no problems but when forced to drive through mud, it caked up and jammed the tires and brakes making the bike almost impossible to ride.

Does anyone publish a chart stating the height or outside diameter of tires mounted on 700c rims? Yes, I know that 35's should be smaller, etc. I just want to know how much smaller so I can get the widest quality tire that will afford me proper clearance.

Thank you.