Numbness with new Renthal bars

[Bigturbomax]

So im looking for some advice. I installed the renthal road ultra low about to weeks ago. I have since been getting numbness in my throttle hand in 10-15 minutes. Trying to determine what the issue is here. I really dont like the height of the stock bars. The renthal is the perfect height. Also, i have badly damaged cartalidge in both shoulders so keeping my arms lower helps comfort tremendously. I added some very heavy steel bar end weights and feel almost NO vibration through the bars. My downward wrist angle is straight and comfortable. I suspect the sweep angle is what is giving me trouble. Has anyone else had trouble with this? And, do you think it would help to cut the bars down shorter and bring my hands closer together? I think the width is what makes the sweep seem like too much on my wrist. Did yall leave youre renthals the standard length?

Pic for attention lol

[Bigturbomax]

I should mention that i normally could ride an hour before my hands got numb with the old bars

[r1limited]

It is my un scientific opionion based on me flunking my PhD in almost everything

The repositioning of your hand and body from stock to the renthals has now placed more emphasis on your wrist.  Meaning the wrist is now in a different angle, adding your finger location if it is resting on the front brake, depending on if this is the middle or index finger can be putting stress on and including blood flow to your hand.  In my personal experiance if I use my index finger on the brake my hand just below the wrist will tighten up, and if prolonged start getting numb.  If I use my middle finger it all goes away.

 

So it appears, because now you are more at an attack angle, more weight on that wrist..... Could be just a matter of changing the angle of the brake "If your Finger(s) rest on it" or the slight difference of the bend in your wrist is pinching a nerve, cutting off circulation or something more ..

[Bigturbomax]

Ok, all good points. I hadnt thought of the levers being an issue. I do rest a finger or two on the levers pretty much all the time. Its just odd as ive ridden super sports that didnt make my hand numb this fast. In fact i dont really have much weight on my wrist since its such a small change in angle. So posible lever position issue or still could be sweep to extreme for me

[r1limited]

I had a set once that cause my forearm (ulna Muscle to just start cramping like arm pump from elbow to wrist.  It dawned on my the bend was not just tweeking the way I gripped but caused me to feel like my shoulders were pinching.  Best way I could describe it was causing your elbows to twist/flair upward.  Tossed them in the first ride, I am very particular on feel.  The bars I have now on the FZ, I made a small adjustment downward just maybe 2 mm and made all the difference. as my starting point is always havng the End bar (Grips) Level with Ground

[gregjet]

I did a post on this, but I am not sure it was on this forum, or the GS500 Suzuki one.

Hand numbness is MOST often caused by either,

Tensing up your shoulders, especially when also riding with stiff arms. Check you are pulling your elbows downwards while you are riding, and relax the whole arm. Straight arms hinder your steering as well.

or

The angle of your hand is causing pressure on either the nerves or the blood supply in you hands as a result of a band bar/hand interface. Sorry to those who have seen this before if I have posted it. I can't find it to link.

 

I will post here again incase it was on the other forum. Should do a post in the "How to's"

Your hand has a natural angle of grip. Anything else puts a load where it shouldn't be. That angle is dependant on arm and body position.  That means seating position relative to the bars, the angle at which your body is when you ride, the width of the bars and your footpeg position ( everything is linked).

Your need to fit the bars to your body, not the other way around. Bars are cheap and there are plenty of shapes and widths available.

First picture is a set of bars ( coincidently a set of Renthal ultralows which are my preferred bars FOR MY BIOMECHS). I have used the lines on the table to help show the changes in orientation.

As you can see, the bars are set to line up .

Notice in the second picture I have let go of one side ( body/arms same position). You can see that the bars have skewed into my natural angle FOR THAT arm/body position.If I was sitting with my body and arms like that on the bike with the bars bolted on,  there would be bad pressure on parts of my hand. That would/could cause numbness in my hands/arms/shoulders.

Third pic is me in about my actual body/hand psoition on the bike. You can see the bars now line up like they should, and sit fair. That rotataion of the bars also matters as you can see they are not quite vertical at the upright.

 

So choosing bars needs to be done BEFORE you bolt them on. Figure out your proper body /arm position on the bike and make sure you can get a natural angle. Assume the psoition ( do like saying that) , grab the bars with both hands, let go one end. They should stay straight. If not, try rotating the bars, sometimes that all it needs.

If you can't, check another set til you can.

When you put them on the bit leave them loose and check you have the right angle once you are on the bike ( again remember rotation matters). THEN you can drill the locating holes and assemble.

 

 

 

[r1limited]

That is one nasty scare on that knee, you should get it covered with a Tatoo that gives it fangs or one big zipper

[Bigturbomax]

Thanks gregjet! That was very informative. I think ive become more sensitive to these ergonomic changes than i once was. Im not old, but not that young anymore either. Mid 30s and spent the last decade professionally wrenching cars and trucks. Its done wonders for my wrists and hands (sarcasm). Also, as i previously mentioned my shoulders are in poor shape-60% labral tear in the left and havent MRId the right yet but it has the same problem. Before i left work, i loosend the clamps and rotated the bars forward and back trying to find where my arms naturally wanted to be. Ended up canted several degrees further to the rear than before. Of course i adjusted the levers to suit. Actually put the levers a little lower taking into account R1s thoughts. I dont want to speak to soon, but i didnt feel any tingles in my hand on the way home. I will report back tomorrow. I will take the long way round to get to work and see how i fair. So far its already much better.

[Bigturbomax]

Ok, so took the really long way to work....12 miles out of the way lol down a county road i recently became familiar with. Cover almost 28 miles and started to feel the teensiest bit of numbness toward the end of the ride. Once i got to work and adjusted them back a smidge more toward the rear of the bike. Like butter. I cant believe how poor of a job i did on initial install. I should have noticed the increase in pressure toward the outside of my palms. In any case, i covered now another 20 miles at lunch time and the numbness had not begun to creep yet. I feel far more comfortable with the bars where the are now. Reminds me of a proper sporting bike now. Wind is noticeably less bothersome on the freeway. I think i got it nailed. Thank you SOOOOO much for the words of advice guys. I really do appreciate it. 

[Cruizin]

You can also fill the handlebar full of silicone. 3 tubes outta do it. 

[r1limited]

Ergp. Ergo, Ergo

Glad you found that zen point in set up @Bigturbomax

[gregjet]

"zen point"

Good description actually. I will now officially steal it. The point where there is nothing and all is one...pretty accurate.

[gregjet]

Couple of things.

First I forgot to mention that people often have DIFFERENT angles for either hand. In that case you could try an average or better a bias to the right hand ( the most used hand because of the throttle.)

 

Also. You mention damaged shoulder. I have a damaged neck from mountainbike accidents. Both the shoulder and neck can cause pinches to nerves. It makes it even more important you pull your elbows downward and relax you shoulders. You will find you tend to tense them up the longer you ride. Takes a conscious effort to keep them loose. My arms can lose ALL feel if I don't.

[gregjet]

" You can also fill the handlebar full of silicone. 3 tubes outta do it."

Actually Renthal ultra lows come with a ureathane insert down the middle already to dampen vibration.

[Bigturbomax]

Still no numbness. I need some free time to really go put 30-60 miles on to be sure the problem is really solved. Interesting side bar; since rolling the bars back to find that magic angle for me, the bars are much lower. In a pleasing way mind you. So i wasnt getting the full benefit of the bars in any way previously haha!

[r1limited]

32 minutes ago, Bigturbomax said:

In a pleasing way mind you. So i wasnt getting the full benefit of the bars in any way previously haha!

Why is it my miond goes to the gutter with things like this.  I mena like when they tel lyou to put your cell phone on vibrator I get the same thoughts