Bad vibes at 5k RPM

[Skyboy8950]

Hey all,

So I just got done putting everything back together after replacing my head gasket on a GS650GL. Now when I ride, I start getting some engine vibrations at 5k rpm. What could this be?

The valve clearance on some valves is a little outta spec, but this was like that before I replaced the gasket. Also, I would have had to get all new shims and go through that (yes I know, I should have while I was there, but I figured that it was fine before...). What else could be causing this shake?

Other than that, the bike runs like a dream. Thanks for the help!

[chef1366]

After you get the valve clearance adjusted properly do a carb synchronization. Did you replace the intake o-rings?

[Skyboy8950]

Carbs were synched prior to head gasket replacement right after I did the carb cleaning. I also replaced the intake o-rings when I did that. I assume the carbs are still synched as I did not futz (technical term) with the adjustment on the synch.

Should I adjust the valves myself? I think I need a special tool to get the shims out and don't know how hard it would be to adjust. Thanks!

[Nessism]

Any time you take the carbs off it's a good idea to resync them.

Valve adjustment is not difficult at all but getting the shims you need could be a pain depending on your local support network (shops that either sell or will trade shims with you).

[Odinist]

Weird! I was just about to post something very similar!

From about oh, 4,800 to about 5,500 I get a really weird vibration/sound... everything below is smooth as silk, and once I pass it, it get better.


Let me know if you figure anything out!

[Dave8338]

As mentioned...adjust valves, synch / resynch carbs.

[80GS750]

mine vibrates too between 5 and 6.5k rpm... its smooth before and after that

its like a really high pitched fast vibration too.... i can feel it in the whole bike, i just figured it was normal for an engine like this to vibrate a little