I rebuilt a fishing engine last week. Was a 1980 70hp johnson. Originaly with the small cast crank. I fitted a newer forged crank. (only one we had) I had to slighlty modify the inside of the piston skirts as the crank was hitting because the Webs are bigger. Much bigger.
Has anyone played with putting the smaller crank shaft in a late model 920cc 70? Is the lighter smaller crank better or does the loss of crank case compression make it worse?
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