Maybe it's me but it looks as though someone has peened the shaft to make it tight. Might just be the way the M130 cam is assembled, as I said, I am not familiar with the engine.

Frank R. would be the guy to ask.

You might try a good soaking of a knocker-loose product, slip a couple of wooden wedges between the gear and housing, re-install the cam holding bolt and washer, back the bolt out a couple of threads, use a wooden dowel as a drift and give the head of the bolt a few gentle taps with a hammer. Worth a shot.

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