Alright everyone I need your help!!! I have a 06 yz 450f that ive had for about a year now and is in really clean condition and I maintenance the bike every week! Haven't had any problems with it until a month ago completely stumped on what it could be! The problem is its impossible to start and the only way is to turn the choke on and pull the hot start lever and it will fire up around 2-4 kicks. Once its on you have to immediately get on the gas or else it will die out. It even has this problem when your ridding and also has a lot of deceleration popping out of the exhaust pipe. All this is actually result of the engine jumping time a week before and after re timing the engine is when I came upon this problem. What ive done so far to try and fix this problem is re shimmed the valves they were slightly out of spec, replaced the spark plug 3 times incase I magically got 2 bad plugs out of the box, cleaned the valves and head and everything in there was all in spec, checked engine timing and valve clearance a hundred million times!, cleaned the carburetor 5 times and all the jets are clear and was all put back togeather to spec with stock jetting, bought and new hot start cable and choke, and ive also checked the simple things like making sure air filter isn't over oiled, engine oil is topped off, and I replaced the gas in case I had the curse of having bad gas! lol im at the point where I think my problem is ive been working on my bike with tools when I should be using a hammer and swinging it at every part! I am down to thinking that the stator is bad! does anyone have any ideas or heard of similar problems? anything will help!