If that doesn't work, you could rig up another old game device from places that had pinball etc.
The one where you popped in a couple of quarters then tried to hang on to the handles as long as you could, as the electrical current got stronger and stronger. Rig it so that the hotter the engine gets, the more current flows; and attach the leads to a sensitive part of the body. Since Fred has Mr. Gizmo's old bike, I think it/he would be the perfect one to experiment on. :O