07 kx250f enngine locked up?

Hi, i was riding my kx250f the other day at a track and when i landed of a jump, my engine cut out. I tried starting it up again and the first kick was super hard, but then i was able to get it started, ride a couple of feet and it cut out again and the kick starter wasnt budging this time. Took it home, and when you bring the cams dead center, the piston moves fine and the kick starter kicks once and then locks up again. took the engine apart, top end was fine, the gears in the kick starter were fine, saw a little into the crank trough the top end and that seemed fine too. I dont know what to do from this point, if you guys can help me out itd be great. thanks.

I'd pull the clutch plates so there's no mechanical connection whatsoever between the engine and trans. If the engine then turns freely, something's broken in the trans. Just thinking of narrowing it down quickly.

I had a broken shift fork and a missing gear tooth that came out of nowhere. Locked things up nicely.

Does the motor move freely if you take Out both cams?

Thanks, I took it apart more and sure enough something broke in the tranny. Thanks alot for the help man

what broke in the tranny? pictures if you can please.

photo.php?fbid=1722938041977&set=a.1180462480427.2025072.1494133110&type=1&theaterIm still not sure exactly what broke, but I do know it was something in the tranny cause when I opened the case to the magneto (I think its called) there were broken metal shards magnetized to the electrical parts. Im waiting on a flywheel puller to actually see the true prob. I am takink pics though and once I find out the prob, ill try and post some for you guys. Edited by MSN629

Ohh, I thought you said you allready had the cases split..

Sorry to hear that - I know that feeling exactly. I bought the flywheel puller - money well spent, but I used a steering wheel puller with a couple really long bolts to pull the case apart. When I did so, the left crank bearing stayed on the crank, so I used a press to put the cases back together.

Best of luck with your rebuild.

ok. So i split the cases aparat today and guess what.... i was wrong. the tannys fine and im guessing the metal i found on the magneto/flywheel was just normal wear and tear? but the real problem that sticks out is that when i spin my crank, it spins a couple of times, then gets dead stuck... im guessing thats not supposed to happen haha, so would i have to replace it? and if so what tools would i need? thanks

msn629, i'm having the same issues with a 07 rmz250 wondering what you found.

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