There's a long bolt that runs through the frame and engine under the gearbox. The nuts on it used to come loose on mine back in the day. To the extent I carried spares. I did thrash it a lot though. It will let you know by starting to feel queasy in corners. Presumably LocTite solves the problem now, or Nyloc nuts. Original front brakes weren't a patch on the better drums of their day. Loved the engine.