Normal
A steel sleeve ( with poor heat transfer) plus a forged piston ( that expands faster than an OEM piston) plus riding before several heat cycles plus unknown ring end gap = a cold seize.You can have that sleeved cylinder plated to help, but it still will have to be properly assembled and broken in prior to any hard riding or it will do it again.I would do a leak test and go to a colder plug to help.What fuel mix are you running?What octane fuel are you using?Was the head squish corrected for the bigger bore?Paw Paw
A steel sleeve ( with poor heat transfer) plus a forged piston ( that expands faster than an OEM piston) plus riding before several heat cycles plus unknown ring end gap = a cold seize.
You can have that sleeved cylinder plated to help, but it still will have to be properly assembled and broken in prior to any hard riding or it will do it again.
I would do a leak test and go to a colder plug to help.
What fuel mix are you running?
What octane fuel are you using?
Was the head squish corrected for the bigger bore?
Paw Paw
