- Local time
- 9:41 AM
- User ID
- 4
- Joined
- Dec 3, 2015
- Messages
- 52,682
- Reaction score
- 350,975
- Location
- Banner Springs Tennessee

Looks like the rod bearing on the big end is the epicenter. I had that happen one time on a Yamaha YZ 80 running it wot for 4-5 miles. But it didn't blue or bend anything. It just came apart and sent bearing shrapnel everywhere. Cylinder needed over bored, new crank pin, bearing, piston ect.
This is just a case of improper heat testing of the parts I believe. Bearing pins got out of shape, and it was all downhill from there. I still have the OEM crank. Gonna have it rebuilt with OEM parts and get another slug. See if it lasts this time.