Morning,
I went to my sisters on Saturday, 30 Motorway miles with no problems. Came out about 5 hours later and the rear was totally flat, I had a repair kit and a pump with me so pumped it back up and threw on some some soapy water...no bubbles at all on the tyre, the bead or the valve. What's stranger is that the tyre then held 38 psi until the next morning when I left. No problems on the way home either....it's a bit of a mystery and has left me wondering if it's going to happen again.
Now I lost the dust cap a few weeks ago and haven't got round to getting another one, the bike had also been standing for a few weeks out on the street and I used the pump to add about 5psi before I left for my sisters. The problem HAS to be with the valve I guess, do you think it could have stayed slightly open when I first pumped the tyre then closed properly when I checked for a leak? I've never seen or heard of this problem before, anyone had the same?
Cheers...Buzz