Just had a look at the valve stem on the rear wheel and it was pulled to a steep angle.
Oddly, when the valve was at the top of the wheel (12 oclock) it was angled towards the rear of the bike. I would have thought that, if the wheel was rotating forward under load in relation to the tyre the valve would finish up leaning towards the front of the bike.
Is it slipping under breaking? or is something else going on? can do without the valve stem being pulled out-
I think the angle of the valve IS correct if the problem is tyre slip on rim during acceleration.
If I stand at the rear brake side of bike, looking at the rear wheel this is being pushed counterclockwise by the chainwheel. If the tyre is diggin-in then it will be forcing itself in the opposite direction. The tube clings to the tyre and thus is forced in this clockwise direction too. If the valves at 12 O'clock and the tube is being forced clockwise, then the valve will start to lean (against the pivot point as it comes out of the rim) pointing towards the rear of the bike.
Correct me further if I am wrong here...............
-- Edited by Wheely on Thursday 5th of August 2010 10:22:09 PM
I would have said that the valve stem would be pointing towards the front if slipping under drive and to the rear under braking.
Anyway get one of these Talon rim locks from 'Tyre Marks' he holds them in stock. I had countless problems with my tyre spinning. One of these puppies installed and an evening round Whiteway and the stem is still pointing drecky south.
