I have an 87 zilla with new piston and jug bike ran for one min then blew gasket when I took apart to fix piston had some light scars on it why? Well I took 800 to 2000 wet sand paper to it and removed them is this safe to do and run bike or do I need another new one why did scars happen jug is fine rings fine also can u help

 

If it literally ran for just one minute then thats a good question. Maybe had to do with water in the cylinder. If your sure thats the only damage then its still a good piston.