I've been doing some highway riding finally on my GS and have realized that the vibrations in the throttle side hand grip are strong enough at speed that my hand goes numb after about 20-30 minutes. My left hand is fine however. I'm not putting weight on my wrists and I'm not gripping too hard- the handle seriously just vibrates the shazam out of my hand.

Handlebars are OEM clip-ons with OEM bar-end weights wrapped with Pro Grip 724's.

Is this a characteristic of this bike or do I need to start troubleshooting? If so, any suggestions? The bar end weights aren't side-specific are they?

Ah, the old numb hand.

First: Grip the handle only with your thumb and index finger. Hold for a while. Then release those and grip with the other three fingers. Alternate. Does that bring back feeling?

Second:  regrip with your hand kinked slightly left. You may need to tuck in your elbow a little more to do this. The idea is to change the wrist left/right angle.

Third: If a line is drawn along the top of your forearm and over your wrist, would it be straight or would it jump up at the wrist? It is like this...



or more flat like this....



If the first image, redo your grip to be more like the second image.

Fourth: Check the tightness of your gloves. Sometimes the ever so slight tightness can cause gradual blood flow restriction.

Fifth: Get a cramp buster and see how it goes.



Sixth: If you are real new to riding and are doing a lot of city riding, your hands can become sore and numb until you are more used to it.

Seventh: Do some shoulder stretches before riding.

Eight: Milk in the handlebars 

thanks to someone's advice here I got a throttle rocker and also changed my grip on the bars, it did help.

You might try loosening and and retightening your engine mounts with a torque wrench.  If you really are getting more vibration than you should, this could be the cause.

I have one of those cramp busters on mine. Bought it off ebay for less than $5 from ebay

Good tips, thanks. I'm pretty sure my wrist was flat, but I'll be sure to check next time out. You'd think some rubber isolation washers would be used at key places on the bike or something. There's a got to be a way to reduce vibrations on a bike... What are the engine mounts supposed to be torqued to?

Anyway, I am pretty new to riding (only around 1k miles under my belt) so maybe I'm just still a sissy. 

Anyone ever tried Vibranators? A little pricey but I read a few posts on other forums that claim these are miracle workers... They have a set listed to be compatible with the GS500, though only model years 1991-2009. Did something change from '89 to '91?

http://www.vibranator.com/default.asp

Oddly enough, they're located in my city...

Gloves with gel palms will help a lot particularly with light weight summer gloves, not so much with heavy winter gloves.  I'm not familiar with the bar end weights used with the clip on style bars but the ones in the regular tubular bars are adjustable.  If they are screwed in too tight the vibes are greatly increased, try backing that one that's bothering you off a bit and see if it helps.

I'll add a note about your bar ends. If your bar ends are tightened too much against the handlebar, they don't really do their job. So it's possible your right bar end is too tight?  Just something small to check before spending money. You want it snug so it doesn't move, but not compressed or pressed up against the bar.

- Bboy

Edit: so yeah, gsJack beat me to the punch... Again... But I went ahead and posted what I typed out.

Just want to add - if your carbs aren't synced, it can cause excessive vibration as well.

Are both your bars straight? I remember driving riding my friends cb650c that had a slightly bent in left side bar from a parking lot drop and that little bit was enough to make my hand/wrist get numb or cramp after about 30 minutes.

Also, for the vibranators, you would have to switch out to some aftermarket bars. They wont install in stock 89's since they have the nuts welded in for the bar ends.

Quote from: Big Rich on April 07, 2013, 03:45:33 AM
Just want to add - if your carbs aren't synced, it can cause excessive vibration as well.

+1 on this. Thing is with twins is they vibrate. When you feel your hand starting to go numb wiggle all your fingers for about 20-30secs while keeping your palm on the throttle. It will get the blood circulating again and the numbness should disappear.

+1 on gel grips, good gloves, bar ends & carb sync.

I will add that there is a noticeable buzz zone starting around 6.5K RPM. A 17t front sprocket will help keep the revs down below the buzz zone on the highway.

Wow, this is now the definitive vibration through the handlebars thread, and not even one mention of powdered milk.  Doh...until now.

First mod to every bike I own... GRIP PUPPIES ™ Small. The wall thickness is approximately .15 in/3.8mm, the larger diameter plus the closed cell foam helped my old hands immensely 

Good 'ol foam handgrips can help too, as well as giving a larger diameter than most rubber grips which is easier on the fingers.

Quote from: bombsquad83 on April 07, 2013, 12:01:25 PM
Wow, this is now the definitive vibration through the handlebars thread, and not even one mention of powdered milk.  Doh...until now.

Um, check my first post. Solution number 8 was milk in the handlebars 

Geez, Squad. That's 'cause we all know powdered I'd the worst thing you could do!

Sounds like I might have my bar ends torqued down too tight. I have bar end mirrors clamped onto them, so they kinda have to be... Though I don't quite understand the physics of that solution. Usually it's when things aren't torqued down that vibrations become an issue. My understanding of bar weights is that they add mass to the bar, which changes the harmonic frequency of them and alters their vibration, similar to a tuning fork. Therefore I don't see how having loose or overly tight weights could really change the mechanics of the system.

About the Vibranators though, couldn't I just install them through the back end of the clip-on tube? All that stands in the way is a plastic plug.

With only 10k miles on the bike, what are the odds the carbs are that out of sync? If they are, what would it cost to sync them?

I read on another forum that filling the bars full of silicone can do the trick as well, but I'm reluctant to do this- even though it is a cheap option.

You could always buy a box of 12 Gauge shotgun shells and take the lead shot out of the shells and fill your bars with shot, 25 shells for under $10.  #8-#12 will give you smaller shot, #8 is .090/2.29mm and #12 is .05/1.27mm