at the 350-400 curing temp of standard powders, you will not have any problems with cured paint if it's still on there. it might yellow a little bit, but I would think you'd be OK for the short time the wheels are in the oven... but it certainly won't burn.

If you choose to powder coat, look for low temperature powder to help reduce the temps needed to bake it on. this will reduce the risk of doing any damage to the heat treatment on the aluminum structure.