GQ Brake Pistons

[Silver]

Thats probably right to mate as the rim caliper and even the tyre were incredibly hot. Any ideas what caused them to get hot.

The caliper and thus the pads don't have a lot that pulls them back out of contact with the rotor after you take your foot off the pedal - just the tension in the piston rubber, and the lateral movement in the rotor bumps the caliper back too.

the caliper slides on two bolts - the same two bolts that locate the caliper to the rest of the brake. Crud builds up between the two bolts and the holes in the caliper, to the point where the brake pads stay in contact with the rotor.

Now, the only time I have had a disc brake get anywhere near as hot as you describe, a stick had trapped a rubber brake line, and pinched it closed. Fluid went to the piston, but could not escape and the brake was locked firmly on.

It could be that there is something in your brake hydraulics that is not letting the fluid back to the master cylinder and the pads/caliper to retract from the rotor. It could just be that the slides mentioned above need some Lurve :-).

If it was as hot as all that, might be worth considering regreasing the wheel bearing?