Well dam dam dammit!
Sorry to hear this.
Tell your neighbor not to feel bad, he had no way of knowing.
Part of that centrifugal weight probably broke off the first time, then the pin or another chunk of the weight blew off the second time.
Id pull the valve cover, pull the bolt, pull whats left of the decompressor system and see what is left of it. Compare to the threads on the removal...
Then put it back together the way the guys are running it with the longer stock bolt.
Then you should be able to see exactly what parts of that system are missing.
We can assume at least two pieces have left the building...
Maybe you got lucky and you will find a broken weight and a missing metal pin.
Maybe the little spring is the only thing missing?
If thats all that fell down in the engine it wouldnt hurt much I wouldnt think?
Pull the screen and hope to find any missing part(s) if more than two parts of the whole setup are unaccounted for...
Its not just brp, yama runs it in their 4strokes too, quads and motorcycles and who knows who else.
Its a sound theory, , ,
If only something stronger than pot metal was used for the MOST STRESSED part in the WHOLE SYSTEM!!!!
Kind of like the plastic gear that fails in garage door openers, some parts just need to be stronger.
Scientific mumbo jumbo...
An engine features a decompression mechanism that extends through a bore formed in a camshaft. The mechanism has an actuator that is formed of multiple shafts. The shafts are joined in the region of a decompression pin. The actuator rotates relative to the camshaft and the rotation drives...
patents.google.com
Readers digest version...
Anyways
Rant off
Srry about your quad man
All is not lost
Nice fresh engine like that will be good to go after a mechanic thoroughly checks it out and you'll be good to go for many years of tearin it up good times.
Best of luck
Oh, I can shoot you the engine manual if you decide to tackle it yourself.
You can always pull the engine and take it to a guy.
Save yourself a ton of shop time $$money$$ pulling plastic and pulling the engine yourself.