Right, so I've given in and ordered a Stans kit from JRA.
I'm fitting new Conti Mountain Kings to 717s.
I've done exactly what the instructions say but with the yellow rim tape (2 layers) and my normal nylon rim tape, and the rubber strip, the tyre is still nowhere near sealing. The air's just coming out all the way round. I'm using a track pump, lots of soapy water.
Tried a CO2 cartridge but that didn't work. I tried pumping with the valve core removed, that didn't help.
What am I doing wrong? What can I do to get the thing to seal?
Thanks
GF.

