UKH

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?

If they're staying up at all, I assume you're running tubes. Are either the tyres or rims tubeless-ready?

Sometimes if the rubber is cold and stiff you just need to add some air and leave it for a day or three. Or run it at slightly reduced pressure and ride it on a smooth or grassed surface. 

Edit. Is the tube the right size to put enough pressure to push the tyre out into place? 

Yes running tubes. I *think* the rim isn't tubeless-ready but I'll check later. I've no idea about the tyre - I can't find any references to it being tubeless ready - does that mean it isn't?

It's the right size in theory (they're 2.3" tyres and the tube goes up to 2.5") although it does feel though the tube isn't pushing out properly.

If there's no mention it probably isn't. What make are they?

Sometimes, especially with tubeless (hence my asking) certain tyres don't get on with certain rims but if neither are tubeless ready then it may be a quality control issue with the bead on the Conti tyre.

Hot soapy water  will help. 

Was the tyre you took off seating properly?

Any recent snake bite punctures?

If you rotate the tyre 90 degrees on the wheel does the unseated section move with it?

Is it a new tube our the old one used again? If new, try a different one. I once had a tube labelled to be up to 2.5, but it must have been labelled wrong and it just didn't fill the tyre at all. If it's not the tube, it may just be a tight tyre. Try working it round towards the part that doesn't sit right. Just physically pull the tyre around the rim from a point 180 degrees opposite, both sides at once towards the tight spot. Sometimes this is enough to get it to seat properly.

Thanks for all the suggestions. Finally got it to sit in by drenching it in hot soapy water, pumping reasonably hard then pulling the tyre with some force. Hopefully having gone in once it'll stretch a bit in case it needs to come off again.

Have had this problem a few times with certain tyres. Most recently a few weeks back on a Nobby Nick. Tried everything I could think of and in the end gave up thinking the tyre was gubbed. Tried a week later. Deflated tyre, pushed bike around with the deflated tyre then pumped the tyre way higher than I'd ride and it popped right into place. Was laughing out loud at how simple the solution was after soap yada yada...

In the past I've had the wheel off of the bike and as I pump it up I bounce the wheel on the ground (not whilst connected to pump) and I heard it popping into place as I did this. 

I have this problem with my wtb nanos, annoying when you puncture, within mine you just need to force to tyre side to side while under moderate pressure and it eventually moves into place, usually takes a few minutes, pretty annoying if you stuck somewhere in bad weather.