Jawa 350/632 - Breakdown nr. XY

It's been playing with me for half a year, but I finally found the problem. At the cost of losing pride and getting back in the back of a van, but finally solved. Reason for all of this mess was incorrect plastic material on the breaker arm camshaft, please see photos in video.
If you want to see my other work, you can find it at these links:
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