bad vibration and noise from my 440

[slickskustoms1]

i have a 99' 440 ex with a white bros. open track cam, pro curcuit pipe, and the carb has been rejetted. some times when idleing it will die. not like running out of gas die, it sounds like it just locked up. but it cranks right back up. also at high rpm it has a bad vibration i thought it maybe the clutch ive got one just havent put it in yet. what do yall think :confused:

[wwclea01]

could be a bent crank or out of balance crank. Thats my guesses.

[Aceman]

That sounds like a bad crank to me also. You might just need to true it, if that's possible. Did someone press a new connecting rod onto your crank? Now is the time to rebuild the bottom end.

[exatak199]

how high of compression are you runing? If its higher than 11:1 and you didnt put a heavy connecting (sp) rod then you might have a bent rod:confused: it's hard to say what’s wrong not beeing there. and how long has it bee doing this?

[cals400ex]

my friends is doing the same thing. we are wondering about the rod, crank, or timing chain tensioner. he also noticed that he had a few loose bolts on his quad. he went through and tightened them all down and it helped a little bit but its still not like it should be. we actually may try a new timing chain tensioner this weekend. i would make sure your valve clearances are correct. we checked that along with rockers and cam on my friends and that all looks good. we are hoping not the rod.