how many times should my crank spin freely while in neutral?

got my motor on the bench, 06 yz450f. top end is off, piston on rod, timing chain and flywheel off. I could only turn the crank 2.5 rotations in either direction before it gets jammed up on something. Is that normal? I think not.


I disassembled it cause I thought I had rod bearing go bad on me, but I'm starting a different topic about that in the general forum. Thanks

2.5 turns is a pretty close match to the primary drive ratio.  I'd say it's either a problem with the primary driven gear on the clutch  basket, one of the other gears driven off of it, or something in the trans on the main shaft side.  Pull the clutch apart and try to isolate it.

Had same issue, it was a rod bearing, needle bearings had flat spots. would spin a bit then bind

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