Question related to excessive vibration

[Kristjan]

I'm diagnosing a problem on the bike I'm interested in. Another 11w.
It vibrates a lot. Vibration is growing with engine speed. Doesn't matter if standing still or doing 160 km/h, so the problem's not in chassis or drivetrain, it must be the engine. Starts, idles, rides, accelerates fine and smooth. No noticable vibration when idling on cruising down the street at 2500 rpm. On the road, 4k or higher, hands soon become numb from the vibration and things get worse with added revs. Rear two engine mounts and the bottom ones were all tight, but could't check the front ones because stuff being in the way. If I assume they're OK, what else could it be? Don't think it's carb balance as idles perfect and the internals are all stock. A plug misfiring is more likely, but should'nt this affect performance as well, which is good? Bent rod maybe? Any ideas would be great.

[Kristjan]

Any ideas? All engine mounts were OK. Could clutch cause this?

[kokolis]

Hi, I suggest you check the ignition pulser and re check all mounts and bolts.
In the past were cases of vibrations ocoured by off balance cranks.
When did you first notice it?

[gsxr884]

what bars are fitted, are the standard bar end weights still there. if it was anything really bad you would feel it through your knees on the tank and your feet on the pegs too

[gsxr884]

what bars are on it ?. bar end weights ? can you feel it through your knees on the tank feet through pegs ?.

[Kristjan]

Stock bars and weights. I did feel the vibration through the tank when I squeezed it hard with my knees and it was also felt through the pegs on a long ride, I have 750 style pegs without rubber covers and stock 1100 mounts with rubber damping.
I think that kind of vibration is just something I have to live with for now.

To be honest, I lost some vibration after modifying the exhaust. I removed and blanked the outlet for the left muffler, gutted the midpipe for a right muffler and enlarged the outlet of the muffler because I didn't have a proper end can at the moment. Stock was internally modified before by someone else, too, to make it more straight flowing. That's a cheap modification until I can get a K3-K4 Ti headers and a proper free flowing muffler to use with a K&N filter I've bought but not installed yet.
Jetting still seems to be a bit rich on highway speed (about 4000 rpm) but I'll blame worn emulsion tubes for that!
I always thought the exhaust header from a 95 onwards 1100W-s was strange and not the best design because of it's outlet for a left muffler.

All mounts and bolts always appeared to be OK. It got annoying for me to always find out that nothing is ever wrong with them, and I stopped checking.