Log in

View Full Version : 400ex motor noise?



81 clark racing
02-16-2009, 03:19 PM
i just picked up a 05 400ex and when i start it up it sounds like a knocking noise coming from the motor. it sounds high in the motor. once warmed up it goes away and sounds good and u only hear it once in awhile. what do you guys think it could be? i no its not the valves i just adj them and rechecked them. i think it may be the cam decompressor or whatever? its 100% stock also. thanx 4 any help.....

Honda#4
02-16-2009, 05:40 PM
Stretched Cam chain or worn out tensioner.

81 clark racing
02-16-2009, 05:59 PM
thank you. i planned on putin in a 450r cam chain and a hotcam anyway