XL600r Decompression Valve - Noise - Help!

2 replies to this topic
  • foeix

Posted February 15, 2008 - 04:01 PM


My top end has had a ticking/metal on metal noise since I purchased it. I had adjusted the valves hoping to quiet it down, and it did some what. The right side seems to be where the noise is coming from, still. I have adjusted all the valves to spec.. so I think anyway. The noise really quiets down when I engage the decompression valve slightly. Does this indicate that my right exhaust valve is too tight or too loose or what? Any ideas.

I have also read that the cam chain tensioner can cause a similar noise.. so that may be part of it as well.

Any one here care to run some ideas or explanations by me? Thanks.

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  • jclaus98

Posted February 15, 2008 - 05:33 PM


I had this problem with mine, and mine ended up being a burnt valve. The manual decompressor had been incorrectly adjusted so that it was actually slightly open alot of the time, this ended up burning the valve seal, so that the valve would stick when it was trying to close. Made a awful ticking noise and ended up having to have both exhaust valves replaced. To test for this, remove the valve cap, and slowly rotate the flywheel counter-clockwise, if when you rotate it around andthe valve snaps back into place after opening and closing, it's probably burnt. If it doesn't, just rotate it the flywheel slowly until you can pinpoint where the noise is coming from. Good luck.

  • foeix

Posted February 16, 2008 - 12:45 PM


Well I went back in and lo and behold the right exhaust valve was way outta spec. I must have not properly taken into account the decompression valve. Now she is nice and quiet, at least for a 25 year old BRP.

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