mine did thatt...i put a new spark plug in it and charged the battery fully and now it runs like a dream

 

Ok guys, I put a new starter clutch in . No help. And by the way, if you ever have to replace this part, the flywheel puller that the clymer manual calls for from motion pro to release the flywheel, well it sucks, that's another story.
Anyway, still had the whirling and no cranking the motor. I took off the right side crankcase cover and first thing I saw was the cam chain off the timing sprocket. So there is my prob. Anyone had this happen to them????
I cannot tell if it is broke or not. I'm going to do some more digging on it when it gets abit warmer, I hate working in a cold garage. If anyone has had this happen, please share your experience.

 

chain tensioner gone bad.

 

beware that if you have a broken timing chain or thrown one that the piston is still in motion but the valve train stops. well hopefully your valves were seated and not in the middle of an intake or exhaust cycle causing the piston to slap and bend them. you probably know this already and/or correct me if i'm wrong. i just wanted to throw it out there. best of luck keep us posted.

bowz

 

clean your carborator lol it probaly has just dirt in it or your starter is broken

 

Mine did the same thing just died and wouldnt crank up at alll! it was my chain tentioner the spring had broken inside it.... threw the timing chain off and sent the piston up and broke my exhaust valves... i didnt know what had happened till u pulled the head off... I had no compression or anything.. i bet thats what happened to you.. expecially if you have a 440ex and didnt upgrade and go to the bigger timing chain thats made for that bike.... so broke ur chain or timing tentioner broke.. one of the 2.. take the tentioner off and take it apart and see if anything is broken there... then take a light and look in the hole and get a screw driver and stick it in there and see if ur chain is still there or not.. woth a try before you take the top end off..