vibration please help

[erok011]

i have distinctly more vibration after replacing my spark plugs. it is at all rpms but most pronounced at 6500. it has got to be a resonance issue because it goes away when i pull the clutch. please help i am stumped

[rexazz2]

my 04 750 vibrates bad at 110kph
the guys I ride with like that speed
I thought it was less when squeezing the clutch also but it really decreased with a new front tire and bearings

[Balsam]

Ride around for ~10 minutes, then park. Lick your finger, and tap the exhaust pipe coming off of each cylinder. The spit should vaporize instantly, like water on a hot stove. If one pipe is just very hot but not to the point of vaporizing water instantly it means that that cylinder isn't firing. That really shouldn't cause a lot of vibration... just a lack of power. But who knows, it might. That's really the only thing that could happen as a result of changing your plugs... if one plug wasn't firing for whatever reason.

Try this: put the bike on a stand (so the back wheel can spin) and crank it up. Run it through a few gears and see if you see the same vibration. Try running in through the range in neutral. If nothing happens in neutral, but you get vibration when you're in gear... something's happened with your transmission or your back wheel has become out of balance (maybe you lost a balance weight).

Also: you said it goes away with the clutch in. Do you mean that at the same engine RPM there's no vibration when you have the clutch pulled in? Or do you mean that when you're rolling at speed, and you pull the clutch in (and the engine RPM goes to idle, but you're still rolling) the vibration goes away.

[hardlydangerous]

sounds like its only running on 3

spary WD-40 or water on the headers after running for 30 seconds
if you have as bad plug that header will be cold and the liquid will not evaporate instantly