Dear bicycle mechanics patron,


I have two questions about tubes, which need a somewhat urgent answer, as you will see soon.


Q1: I had my front tire go flat. I thought it's a snakebite, as I was running it at low pressure to maximize traction on snow/ice. Came home and found that the "puncture" is actually a cleft near the base of the valve (Schrader). The crevice is about 5 mm long, perpendicular to the axis of the valve, and about 2 mm from the base. Given these parameters, do you think it's worthwhile to try and fix this tube, with the usual vulcanizing glue and patch? Note that the rent is rather shallow, and only the central part of it seems to get all the way through the rubber.

Q2: I have a spare 26" tube of the appropriate width. Problem is, I abhor it. It is a Kenda "Schlauch (tube) mit pannenschutz" - that is, a tube filled with some nasty goop, which theoretically would go on filling potential holes, thus rendering the tube "puncture-protected". I hate this good, because the one time I tried one of these tubes, it seemed to want to escape from the tube and fill my pump, and gunk it up. In fact, I did seem to have some issues pumping with that pump, afterwards, for a while. The question is: is there a safe way to pump this sort of tubes, and am I just paranoid, and nothing ill will happen to my pump? Is there some solvent which can wash the hardened goop away, if it does end up in the pump? (Also, is this stuff the spawn of Satan?)


The urgency comes from the fact that tomorrow I need to commute to work, and this is my winter commute bike with the appropriate studded tires. Sans one tube, at the moment.