engine sprocket removal
i know ive seen this posted but cant find it. anyway im having trouble removing sprocket from starfire gt3, ive tried heating nut with torch and using rope to stop piston, turning it counter clockwise, but engine continues to turn. reason to remove, is the thin teeth on sprocket alows chain to move side to side hitting the block, im using 415 chain. dont want to use the reg. bike chain that came in kit. not even sure that the spare sprocket i have will even work on the shaft, but need it off to see. also who would have parts for this motor. thanks for any help.