I noticed that Vittoria updated their Open Corsa Evo CX clincher tires for 2009. They claim improved puncture resistance and an even higher tpi rating. Does anybody have any experience with these new tires? I am really interested in knowing if the rolling resistance has been futher reduced, and if longevity has increased. Also, has anybody measured the true width of the 20 mm and 23 mm Open Corsa Evo CX II tires?
I currently use Bontrager Race X Lite Pros which I understand are largely similar to the original Open Corsa Evo CX clinchers, but with added puncture resistance. I have also used Pro Race3 tires, however, I prefer the Race XLPs due to their more comfortable ride.
On a general note, I have always used 23 mm tires front and back, but am wondering whether or not, the supposedly improved aerodynamics of a 20 mm tire makes using a 20 mm tire for the front wheel worthwhile.
I grew up racing on CX tubulars and it has about as smooth a ride as you can get. Largely has to do with the TPI and the casing design. I would not train on them - just racing given the light weight and rubber composition. Most of the top models from the larger manufacturers will have about the same puncture resistance (i.e. Vittoria, Michellin, Continental, Schwable, Maxxis, etc.) - if an item of debris is going to penetrate the casing and give you a flat it’s going to get in there. There is always a trade-off between weight, feel, suppleness, and puncture resistance. My advice is to reduce pressure when you store your wheels and inflate them right befour you leave your bike in T1. After your race, clean your tires and inspect for cuts and debris and make sure to seal any small cuts in the tread with Crazy Glue or similar. As far as aerodynamics go I would not sweat the difference between 20c and 23c - I would be more concerned with comfort and ride handling. I can blast through corners faster and more confidently on 23cs than I can on 20cs. For me, that’s more significant. Personally I like with CXIIs followed by the Michellins. Good luck.