I've just put a new rear tyre (Continental Gravity FWIW) in my mountain bike but can't get the bead to seat into the rim properly - at one point the tyre wall is about 5mm further into the rim than it should be, which is pretty noticeable when riding. I have tried:
- Manipulating the tyre at low pressure - at about 15psi I can push the tyre wall off the rim but it shows no inclination to move out from the rim.
- Pumping it up as hard as I dare (80psi - they are rated to 65 so figured it was unlikely to explode at 80 not being ridden)
- Repeating both the above with washing up liquid speared on the bead
- Riding at various pressures.
..none of which seem to have any effect. Does anyone have any other ideas/suggestions?