BMW Tubeless Spoked Wheels Maintenance
BMW is the only manufacturer to use spoked tubeless wheels. The design uses a cross-spoke pattern, with the spoke nipple at the hub instead of the rim. The wheels are extremely strong, but need some maintenance. However, they are EXTREMELY difficult to true. The factory builds them on a CNC machine, with a final tune by an expert using very special equipment. Your BMW dealer will not touch these wheels, insisting on replacement, despite the rims being available as a separate part.
Hagon Shocks, UK
I'm told they will repair and rebuild the BMW wheels at a reasonable price.
Woody's Wheel Works, USA
Woody Witte rebuilds GS tubeless wheels.
Woody says: "...$200.00 using good parts. When we try to save the customer money by re-using his existing spokes and nipples we run into problems...trying to dismantle the wheel, frozen/rusted grub screws and nipples, spokes that do not readily come out of the rim etc... we know lot's of tricks to minimize the cost, (but) the clock does tick at $60 hour flat rate, and we are constantly trying to find better deals and sources for these applications."
One of Tims rebuilt wheels
I have personally had the pleasure of truing one of these wheels. Don't bother. Send it to Woody. Trust me! (I've built hundreds of conventional wheels, and it normally takes an hour or so. But the BMW tubeless wheel I trued took me three days to get right. Mind you it was in Peru, in a back alley etc... but it was still very tough.)
One of the tricky parts of these wheels is the tiny little "grub" or "set" screws used in the end of the spke nipple to lock the nipple to the spoke. These are almost invisible, and the first time I ran into them I didn't know they were there, and couldn't figure out why I couldn't adjust the spoke!
Eventually I found it, and then began the hunt for a small enough allen screw to loosen it. The R100GS uses a 2.0mm allen wrench. I believe all models use the same one. Check! Make sure you have one in your tool kit.
The spoke nipple is steel, not brass like the old style ones, so are susceptible to rust. Many bikes with these wheels have a problem with the setscrew rusting in, making it almost impossible to get out. Highly recommended to spray a little WD-40 on them once in a while, or a dab of grease.
Instructions on spoke replacement.
"Get the spoke, nipple and grubscrew (setscrew). Put it in until just tight. Ring some of the spokes with a wrench and torque the new one until it sounds like the others. Install the setscrew. DO NOT TRY TO ADJUST ANY OTHER SPOKES or you'll be sending the wheel to me for a big bill. The tubeless wheels don't adjust like any other wheel so please don't try it. Now give the wheel a spin and see how much deflection you have and maybe you'll see why the spoke is gone. Catch a twig on a trail? BTDT
If the rim is within 1/8" not too bad on the rear for stump jumping. If more you've whacked something and it needs to come apart and be relaced. Ring all the spokes with a wrench and listen to how many sing and how many are dead. Older R11GSs with Akront rims were kinda soft in the torque dept and that might have caused the spoke to pop. In that case it may need a rebuild."
For more information and advice contact Woody or Hagon, info above.
And if you really want to do it all yourself, Ricardo Kuhn and Jon Jen did a major writeup on the job, in pdf format here.