My guess is it got scratched when it locked-up..trying to get the cylinder open maybe?
Could probably do a penetrant crack test...using light weight fast evaporating fluid..(like brake and parts cleaner). Remove grips and cylinder...spray the cleaner on the area and see if the stuff stays wet in the 'crack'...if it evaporates off everywhere but the 'crack'..it might be cracked..if it just evaporates off and no liquid stays at the 'crack'..prolly a scratched frame..
Could probably do a penetrant crack test...using light weight fast evaporating fluid..(like brake and parts cleaner). Remove grips and cylinder...spray the cleaner on the area and see if the stuff stays wet in the 'crack'...if it evaporates off everywhere but the 'crack'..it might be cracked..if it just evaporates off and no liquid stays at the 'crack'..prolly a scratched frame..
