Has anyone seen and overcome this issue before?
I’ve got Latex tubes, and I think the little double thickness collar around the valve area on the tube seems to not slide into the tyre, and pushed the tyre up as I inflate it… I’ve tried quite a few times deflating/inflating but it’s not having it.
Maybe a daft question but did you push the stem into the tyre before inflating?
Yeah, i’m 99% sure It’s hard into the wheel.
I had a similar, but not quite as severe issue with some wheels recently. The bead wasn’t quite catching but wasn’t popping off so I ended up with a thump in the tire when riding. Liberal use of dish soap to get the tire to slide into the bead correctly was the solution.
Opposite direction - push the valve away from the wheel and into the tyre, then push the the bead down to seat it and then pull the valve back out. At the moment the reinforced area around the valve is pushed up hard against the rim and blocking the tyre from seating.
Thanks, that’s it fixed 
