So my 1990 big bear 350 is making a semi loud ticking noise. Sounds like the valves. Last night I did a valve adjustment, and it seemed to help just a little. Still a ticking noise. Is this normal for this particular ATV? Some things I have read is that ticking noise is fine, just how the machine is. I have heard the saying, "noisy valves are happy valves" but not sure how noisy is good or bad haha. I know a video or at least a recording of the noise would be more helpful and can post that later if needed. Any advice or help would be appreciated thanks!

 

The valves on most overhead cam ATVs usually make a bit of noise but who can say how much is excessive? Reasons are usually worn cam followers and/or cam, but slack cam chain, worn rocker pivots, or a loose valve seat, are all possibilities, as is piston slap, though this is faster and tends to lessen as you rev and as the engine warms.

 

Thanks for the reply. Yeah it seems to stay constant and doesn't have a clanking or slapping sound. Just a clicking/ticking that goes with the rpm of the engine. Here is a video of it running. Sorry for the quality. If you listen carefully past all the engine noise you can hear it. Especially after releasing throttle back down to an idle