you're not alone, I've had 3 engines in my bike: on the 1st one the gears went popcorn, changed all under warranty, the 2nd time the main rod that holds the gears snapped in two, the 3rd engine went with the bike when it was stolen, never got the chance to break that one... but I was lucky to buy 2 used ones and I must say the last one was a minter, and run like clockwork...

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