Modifying K12 barbacks for extra handlebar sweep

1. Although the K1200RS/GT offers handlebar adjustment, it does not allow the handlebar ends to pivot. For maximum combat touring effect, I chose to move the bars all the way forward and down, but also I needed to sweep the bar angle backwards ten degrees or so. This not only gives better hand ergonomics, it gives the hands better weather protection. And with the GT's upper fairing extensions (hand protectors) the lowest non-comfort barbacks cause an interference problem between the protectors and the hand levers unless this extra angle is added.

What does this change?
The handlebar ends are rotated backwards, so that the ends are further back and toward the center. I also chose to use the most forward possible position of the standard (low) barbacks.
Why do this?
  1. Rotating the barbacks allows them to be lowered without interefering with the GT fairing uppers.
  2. Lowering the barbacks moves the hands back into the cover of the fairing uppers. Remember that the newer RS nosepiece got wind tunnel attention? Then why are the rider's hands still unprotected in the wind, even in the GT which is supposed to have more protection? Because the K12RS and GT were not designed for an american market, but a european one, in which the lower barbacks are standard. the K12RS fairing was designed for low barbacks, and only gives full weather protection in this low position
  3. Rotating the barbacks takes the pressure off the ball of the thumb and distributes it evenly between the thumb and heel of the hand. This reduces painful pressure on teh hands and gives the rider more variety of adjustment of position to avoid repetition of a single stress.
With the handlebar removed from the barback, you can see clearly the grooves which not only hold the bar in place front to back, but also keep it from pivoting. To increase the angle of the handlebar end, we'll need to make new grooves at an angle.
2. When removing the barbacks remember that there are three bolts holding it on- one connecting the handlbar at the pivot point, one clamping the barback to the fork tube, and one (not visible in the picture) which comes up from behind the top triple clamp adding additional anti-pivot anchoring to the barback. DON'T unbolt the bolt that clamps the triple clamp to the fork tube.
3. Mark the area on the barback where the handlebar pivot sits. This area will need to be ground down below the level of the teeth before new teeth are made.
4. Beginning the grinding operation. The existing grooves actually make it pretty easy to tell how deeply you're grinding, and to get a uniform depth. A die grinder is definitely the tool of choice here.
5. First grinding operation complete. This will make room for new teeth to be made. Although you want to make the area farily uniform and smooth, don't worry about making a superclean finish yet, as the surface visible now will all be ground away. Getting it as uniform as possible will help with the marking operation later, so work over the surface with a hand file to ensure that there are no major high spots.
6. Set the barback onto the handlbar temporarily. From the underside shown, you can see that the handle end has two slugs that fit into the groove to further prevent the handle from pivoting on the barback.
7. remove the barback and the slugs are plainly visible. We'll need to grind away room inside the slot to allow the handlebar to pivot. (NOT grinding the slugs on teh handlebar end- leaving those alone.)
8. Here's the barback marked to show where material will need to be removed to make room for the slugs. A permanent marker is very handy for marking where to grind.
9. The barback with material ground away to leave room for the slugs when the handlebar is pivoted. I switched the die grinder to a burr tip to reach into the slot and make room.
10. Next, we'll need to grind away a bit of material to make room for the handlebar switch unit in the new pivoted position. Remount the barback to the handlebar, and use a marker to show where material must be removed. It looks like a right angle corner from this angle, but it's at an obtuse angle with regard to the barback edge. Just take extra time to mark carefully. Note that the mark is a half centimeter to the left and a half centimeter higher than where the switch unit is. This is to leave room for more pivoting (left) and to leave room when the teeth are added (higher), dropping the barback a half centimeter closer to the switches.
11. Barback removed again, ready to grind.
12. Barback with notch ground. sandpaper helps to clean up and smooth grinding marks.
13. Now remount the barback to test fit. The handlebar can now pivot to match the notch. Note that the amount it is notched in will determine the final angle of the bars- and notching both sides the same amount will make the angles match on each side. It may take a few cycles of this, checking and regrinding, to make the notch clear the way you want. There's still vertical room in the notch because the teeth aren't ground yet.
14. Now it's time to mark for the grooves. Wrap the area to be ground with electrical tape, taking care that it's smoothly affixed to the surface with no bubbles. also cut a hole through the tape to allow the bolt to pass through.
15. Now remount the barback to the triple clamp (not shown) and attach the handlebar end. Before tigthening, make sure you like the angle. Then torque the bolt (20 nm = 177 inch lbs) and remove it again. The teeth in the handlebar pivot will cut into the electrical tape, leaving clear marks where the grooves should go.
16. Using a saw or knife-edge file, cut through the marks in the elctrical tape to make lines beneath in the aluminum. Be careful not to shift the tape as you do this! This operation requires the most care.
17. Remove the tape and use the saw again to deepen the lines. You'll probably get the three center lines, you'll need two more on each side. These lines are where you'll grind into the barback to make teeth.
18. To help ensure your teeth are regular, add marker lines between the scored lines- these will be the mountains between the valleys you'll grind.
19. Use the die grinder to rough in the teeth, checking croos section caefully to keep right angles. Watch the high point marks, keep their width uniform as you go.
20. Although the die grinder is great for removing material quickly, you'll need to use a hand file for precision. This is done grinding and ready to be filed. Make sure the teeth are deep and even, with no high points along the tooth faces. Also be sure to run the file gently across the top of the peaks to make sure they're level- you don't want sharp mountain peaks, but rounded ones.
21. Take time to fit the new teeth against the handlebar ends to make sure they mesh tightly. taking off a little too much doesnt hurt as much as leaving a high point that keeps it from meshing tightly.
22. Now that you've removed a half centimeter or so of material, your handlbar mounting bolts will now be too long. Don't torque them as is, they'll bottom out in the hole before the barbacks are tightly attached. You could cut off the original bolts, but I chose instead to get new bolts and cut them short.
22. The finished barback, ready for the handlebar to be reattached. (torque the big bolt to 20 nm = 177 inch pounds) It looks pretty good- there are some irregularities, but I carefully checked the fit and the handlebar end meshes tightly with the barback. Now my handlebars have the far-forward, swept back configuration that is so useful for long-distance comfort. Plus, the grips now tuck neatly into the fairing's airstream. These barbacks are trick- in only a couple hours' effort I've greatly improved the K1200GT's usefulness as an all-weather combat touring bike.

Disclaimer: this is how I did it, proceed at your own risk. Obviously anything you do to your bike could potentially cause hazardous conditions. If you have any questions, feel free to email me at paulcl@nwlink.com

(Just don't ask me to make a set of barbacks for you- if you want somebody else to do it, these instructions should tell any competent machinist what to do. Expect to pay them extra hours effort for a nice clean job.)