Gsxr 1100 vibration

[Toecutter]

I've been chasing an annoying vibration on my slabby for a while now. The vibration is making my right hand numb after about 40 minutes into riding. I've been over every thing since I have recomissioned the bike. The bike had been off the road for 25 years, so full strip down and replaced every bearing etc, everything refurbed etc. Engine sound, carbs synced etc. Tried various things to try to eliminate the vibration including heavier weighted bar ends. 

Just been for a hoon and still have vibes. Just had a look under the fuel tank and the bottom of the tap is just resting on the oil tube, only just touching. The frame cushions are in place, but I have positioned them in front of the cross rail before the airbox. has anyone any idea as to where they are supposed to be mounted. If I move them back it looks like it'll raise the rear of the tank just enough to clear the oil tube and hopefully sort the issue.

Cheers.

[Gixer1460]

Try it and see if it works for you? Are bars std or aftermarket?

[Toecutter]

Everything is standard apart from yoshi cyclone. Tank rubbers are in correct place with regards to manual. Perhaps after market tap sits a little lower...

[DAZ]

Have heard of peeps filling bars with silicone to damp vibes, if it's not the tap to oil pipe issue 

[slayer61]

Sand, length of steel cable, any kind of weight or buy it from http://www.barsnake.com/

[Gixer1460]

If it was tap on tank, I would have thought you'd feel it through your knees as well? Is the vibe constant or more / less at certain speeds or revs? Maybe wheel or other rotating pieces balance?

[Toecutter]

Yeah, it's quite tricky to pin down. No vibration felt elsewhere, only in the right hand. I get what you mean about vibes in knees through tank though. It's a very high frequency buzz. I don't ride with a death grip either, very loose. Wheels balanced, chain and sprox good, brakes free and not binding etc. High speed riding its not evident, it's in the 3500 to 5000rpm region. I know the older engines are a little  more vibey but this was also evident on the original engine too.

[Gixer1460]

In that case i'd guess you maybe more 'sensitive' to a querk of the design ie. 'they all do it' but no one really notices, or its just a combination of elements that end up at your Right Hand ! ! !  A change of grip material may help?

[Oilyspanner]

Could check all the engine bolts, one might be loose - sometimes loosening the bolts (with a Jack to hold the weight) and then systematically go around gradually tightening them up helps.

Something that I did to help my right hand was to alter the angle of the bars. I've got clip ons above the top yoke and had angled them back - less reach, more upright for more comfort when going slower I thought....what happened was that my wrists were held at an awkward angle. I pushed the bars away from me and just like that my right hand/wrist wasn't a problem.  Obviously you've got std bars, but after market ones can be fitted without changing anything else.

[Toecutter]

Cheers for the info. I have checked engine mounts etc, literally been through everything. Haven't yet adjusted fuel tank as mentioned above however, if that's the case I'm sure if feel vibes in knees and both hands, not just the right side. The plot thickens...

[imago]

On 9/12/2023 at 5:34 AM, Toecutter said:

Yeah, it's quite tricky to pin down. No vibration felt elsewhere, only in the right hand. I get what you mean about vibes in knees through tank though. It's a very high frequency buzz. I don't ride with a death grip either, very loose. Wheels balanced, chain and sprox good, brakes free and not binding etc. High speed riding its not evident, it's in the 3500 to 5000rpm region. I know the older engines are a little  more vibey but this was also evident on the original engine too.

 

It would be a quick thing to check so worth a look, but if it seems to be mainly the right hand have a check of the right hand bar. End of a snapped off bolt, captive nut for a bar end or similar left in the bar would make a high frequency vibration against the inside of the bar.

[Toecutter]

That's not a bad shout to be fair. Worth a peek for sure. Cheers.