I was riding my blaster in about 3rd gear and then i herd something rubbing in the motor it rode for for a couple of minutes longer then it died i got it to start once then it died and while i was tryin to restart the motor i could hear it rubbin still then i took it back to my house then i idid a compersion test and it was at 90 but i didnt hear that rubbin noise anymore then i took off the head and found a pice of metal in the piston but i was able to take it out and it didnt go through the whole piston i havent taken the jug off but i've look down the jug and pushed the piston and down and goes through the motion smooth so any ideas on wat wrong