So you have an early Oilhead with the buttons to provide the floater action. Your bike's got about 50 or 60,000 miles on it and the front discs are rattling like a baby toy. What to do, what to do....
Well, the answer is that the buttons that hold locate the disc on the carrier are all worn out and they're allowing some amount of rotational play. You can fix this in your garage in a couple hours. Here's how.
First off, take off the front wheel. I got mine off and dropped the wheel on top of a milk crate. You don'twant to drag your nice rotors on the ground.
The milk crate fits perfectly
Next thing is to make sure you can put everything back together the way you found it, only with new buttons. This means ensuring that the disc is in the same relative position on the wheel and the carrier and disc are in the same relationship to each other. You'll also notice that there are two kinds of buttons. Some have a smaller hole in them. These have a circlip running around the outside. There are three on each side. Mark their location as well. I used a Sharpie pen.
I used an arrow to point to the valve stem and the single line indexes the carrier and rotor. I put little arrows at the three special buttons so I knew where to put the replacements
There are six allen head bolts that are not reusable holding the carrier onto the wheel. Once you get them off, flip the disc/carrier assembly off and here's our mission.
We need to get these little guys off
I used a small screwdriver to get the E-clips off. I wedged it in the little gap and then twisted the screwdriver to lever the clips off. Go all the way around, taking all the clips off.
Just wedge the end of a teeny screwdriver in there...
...and give it a little twist. Be careful not to scratch the disc.
Once you have all the clips off, the regular buttons will all fall out, leaving the circlip ones behind.
Just the three circlip buttons are left behind.
I gave one of the circlip buttons a knock with a hammer and drift and it fell right out, which let the other ones go free.
Now comes the trickly part, putting the new circlip buttons in. I found the best way to do this was to make sure the little wire was in its groove and then poke the ends into place. This let the button snap into place easily.
Make sure the wire is seated in the groove on the other side and then use your little screw driver to poke the ends into place.
After you have all three of the wire equipped buttons in place, carefully lay the disc assembly down and put the washers and new clips on. I used a small drift and a hammer to drive the new clips on.
After you've got the three set, move on to the regular buttons, working in three segments.
Put the new buttons in three at a time. Drive carefully with the punch so you don't scratch anything.
Now, mount the disc back on the wheel, indexed properly. Flip the wheel over and do the same thing for the other disc.
Here's what BMW calls the parts you'll need.
- 18 each "9-bushing"
- 6 each- "Roller"
- 24 each - "9-circlip"
- 24 each - "9 Washer"
- 12 each - "Braker Rotor Botl - FR"
- 12 each - "Washer"
This whole process shouldn't take you more than a couple hours.
I only have the part numbers for a '94 R11RS, but if you want them, I can send them to you.