R100GS HPN Rear Brake Lever
I first ran across HPN's replacement rear brake lever while flipping pages in a Touratech catalog, and the idea of tucking the lever up out of the way seemed like a good one. The $140 price tag is very high, however, but when some insurance claim cash came my way I decided "what the heck" and ordered one (along with an oil cooler relocation kit).
The kit comes with everything you'll need for installation except a drill. The instructions in the package are in German, however, and like the cooler, there is a help page for the brake lever on the Touratech USA web site (though it's not referenced from the catalog page like the cooler). I was able to piece together the path forward from looking at the illustrations on the German instruction sheet and reading the text on the Touratech web page.
The kit comes with three pieces: the replacement brake lever, a new cable stop for the rear drive end of the brake cable, and a cable alignment bracket for the pedal end of the cable. The latter is needed because the bend in the cable necessitated by the reversed lever makes the cable want to droop as it emerges from the brake pedal housing. The lever is aluminum, just like the original, and is the same length as well. It incorporates a jog so that the cable end will not hit the drive housing. The cable stops and brackets are cad plated steel, as are the mounting screws.
Installation consists of removing the original brake lever and installing both of the new cable ends. Begin by disconnecting the factory rear brake cable, spinning off the big wing nut and setting it aside in a safe place. Also remove the rubber boot from the cable. Pull the cable out of the stop in the final drive housing, and pull the cable out of the stop.
Slide the HPN alignment bracket over the cable with the tail of the bracket pointing up and facing to the rear of the bike. With the brake pedal end of the cable fully seated into its stop, position the alignment bracket so that the end metal ferrule on the cable is at least 1/8" from the bracket. Mark the location of the hole in the other leg of the bracket onto the brake pedal housing. Remove the plastic cover from the housing and drill a 7/32 or AWG #3 hole in the housing. Using the provided bolt and nut, mount the bracket to the housing, again ensuring that the bracket is at least 1/8" back from the end of the cable ferrule.
Next pick the HPN cable stop out of the kit. It will re-angle the brake cable housing so it aligns with the new brake arm. It's not very intuitive how the new stop should be mounted, but the stop has a tab with a hole in it, through which the mounting bolt is inserted. The bolt then passes through the original anchor location of the cable on the drive housing.
Thread the cable through the stop and make sure the cable housing is bottomed in the new anchor. Slip the rubber boot over the cable.