so my axis has 35c irc mythos tires. the guy at the lbs gave me 28/32c tube as a spare. well, got my first flat today on this bike and the punctured tube i removed was a skinny 18/25c tube. not sure if the skinny tube is from the factory or put on by the lbs during assembly, but what's the deal? what size tubes should i be running in a 35c cross tire? on a recent off road ride i went down to about 40psi front and back but flatted today on the road at 75psi.
I run 18/25c tubes in my 32 tires mainly because they're the only ones I can find with long enough stems to fit through the 27mm deep rims. I'm about 130# so even running at 75psi doesn't give me problems. If you're a big guy, you might want to switch the tubes to the thicker 28/32 tubes if you're going to run at high pressures.