Don't put in the oven, just get a match or lighter... hold it on for 5-10 seconds then quickly onto rim. You've got about 5-10 seconds until it goes back to being hard.
It was freezing cold on sunday, felt like 0 degrees and about 20 people turned up for the Skegness ride. So people do come out, just gotta go find a ride.
A cycle shop near mine applied this sticky glue substance on the tyre to make it stick to the edge of the rim. But they then realised that they had bought a front tyre for my wheel instead of a 19''.