I don't get it. I have never had a pullstart break. Ever. My .28m was crazy tight when new, I could pick up my truck if not careful. And mine is HEAVY.
I rate this engine as a 10. My old rb was not this nice at $300.00.

Pullstarts are an item that is easily abused. That's why they don't last. As Dino said, this is a race-level engine. The compression when new is crazy. No pullstart will take hard yanks of the cord. I say way to go STS!! I wish my past engines were this nice, especially for what I spent on them.

Dino: Maybe a more serious caution should be added to the instructions.

ozpall: My instructions have shim recommendations. Do the new ones not have that?? (not sarcastic) The instructions do not say "after beak-in change to this" and maybe they should.