The tube is a regular specialized 20', but I'm tempted to try a danscomp street tube: http://www.danscomp.com/446040.php I use 18-20 psi generally, and I do feel the rim hit every now and then. I'm wondering if the holes in the echo rim might have something to do with it, since my dx 32 was not drilled?? I will try the chalk powder though, I used to do it but stopped cause I'm lazy