Bike is hard to kick and wont stay running.

[HONDAF]

I was riding my bike fixing to hit a tabletop I was in like 3rd gear almost pinned. It suddenly just shit off then wouldn't start the rest if that day. I took it home changed the oil and air filter (there was little tiny metal flakes in the oil) it started back up first kick. I rode it around my house a little bit and when it got past like half throttle it would die. Now when I start it, it feels likes its grinding and when it starts it runs for like 5 seconds then dies.

[jetboatrich]

sounds like your top end is gone, piston seized

[2012rmz250]

same thing happened to my 2012 rmz 250. My piston had has a huge scar on it and warrped the cylinder. i also have flasks of metal in my oil filter and i changed oil. its hard to kick and it grinds. i went to kick it and it make a clank crunch crunch noise. i shifted down from 4th to 2nd in air thats what did it for me. and it just locked up on me one day. took it to the dealer and they said it would be $3000. its in pieces in the back of my truck atm. good luck with it. middle finger to 4 stroke repairs. bye bye loretta's