Hello everyone, i am in need of some advice, i have a noise in my polaris and its driving me crazy! recently i rebuild the bottom end, all new bearings, seals, ex. it has oil injection removed and a westco piston .030 over. now i have 2 video's of it running if you guys could watch and give me some advice on what you think it is.

Video 1
YouTube - Polaris Running 2

Video 2
YouTube - Polaris Running

thank you

 

did you rebuild the crank too? could be the rod moving around or the piston is slapping...hard to tell tho

 

Well first off these things are noisy, that counterbalance shaft. With the gears that drive are load. If you think it is not a rod bearing, or excessive piston clearance. then the next place to look is the counterbalance. One of mine was really loud because the woodruff key and keyway in the gear were wore out causes lots of backlash.
In person I might be able to tell you but that video it's hard.
Put a stock pipe and silencer back on then listen to it again.

 

i listened to your videos the best i could, i didnt hear anything out of the ordinary.

BUT,if yours is a 400 sport, chances are, due to its age, the primary clutch needs rebuilt. they have a way of mimicking engine noise quite well when they are worn out. a good way to tell is if the noise goes away when you rev the motor.

another place to check is inside the recoil housing. i have heard stories of things coming loose inside there and causing quite a ruckus.

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