Hi, so, during a ride, my engine decided to stop working and it lost compression. I found that the problem was the small bevel wheel. The pin, or whatever it is that holds it in place, was gone and the bevel wheel itself had a fine crack in it. Ive got the correct spare parts for it, but how the hell do I put them back on? I needed no tools except for a screwdriver to undo the bolt/screw, and the bevel wheel just lifted off with ease because of there being no pin. Please help