A little back story on the bike. I bought it a few weeks ago, went to ride it and it was reaaal boggy. So, I rebuilt/cleaned the carbs and installed new jets (40/140), new spark plugs, and a new K&N Lunchbox.

Just got it all back together tonight and started it up. Once I realized I forgot to turn on the tank petcock , she fired right up. However, once warm I get an off and on knock. It isn't THAT loud, but its noticeable. It kinda sounds like its coming from high on the engine. I did a little searching and read that it is a common problem on GS's and is generally harmless. Is this true and what causes it? What else could it possibly be? I never heard it knock before the carb rebuild, but then again, I barely had it running at all.

After three weeks of owning the GS, I haven't been able to ride it at all. I'm ready to get on the road! Just wanna make sure things are OK first.

Sounds like it could be the common camshaft knock.  Does it only when warm and only at idle, pick up the rpms a bit and it stops.  Caused by too much sideplay in camshaft, it knocks back and forth and is harmless if that's what it is.  My 97 GS had it off and on for the 80k miles I used it.  My 02 did it briefly and I've not heard it for a long time with 59k miles on it now.  If I heard it, I'd know it for sure.

Thanks for the info. Yea, It only happens when warm and at idle. I don't hear any knock under and load. So it looks like I'm okay. I've put about 55 miles on since that post and everything seems alright.

Quote from: gsJack on May 21, 2008, 07:24:30 PM
Sounds like it could be the common camshaft knock.  Does it only when warm and only at idle, pick up the rpms a bit and it stops.  Caused by too much sideplay in camshaft, it knocks back and forth and is harmless if that's what it is.  My 97 GS had it off and on for the 80k miles I used it.  My 02 did it briefly and I've not heard it for a long time with 59k miles on it now.  If I heard it, I'd know it for sure.

Thanks gsjack! I was initially annoyed by that noise. Now I have gotten used to it. Moreover, as you said, My noise disappears at RPMs greater than 1600 or so. It is only during the idling and startup that I hear that.