Originally Posted by
goomba271
"The presta valves tend to retain air in the tires much longer than the standard Schraeders." Hi - Just curious... are all other factors identical? I.E. type of rubber (Butyl vs Latex), age of rubber, thickness of tube, absolutely puncture free, etc??? I've had tubes with tiny pinhole leaks that I could not identify without really pumping them up and squeezing them under water. I've also had Presta valves that were not properly seated in the stem that leaked slowly. There is a little O-ring where they screw in to the stem. That has to be compressed a bit for them to seal. Same with Schraeder valves... they have to be screwed in tight to remain leak-free. Seriously - if all is as it should be, the type of valve should not be an issue. By the way, I'm not advocating one over the other, just questioning the reality of one holding air better than the other.