ABS Brakes on the BMW R1100S
I noticed about two weeks ago that something was misbehaving on my BMW R1100S. When I came to a stop, had the clutch and front brake pulled in, my speedometer would start bouncing around. Big question marks started running through my mind when I saw this. This isn’t supposed to happen.
I disregarded it. Then I noticed that after starting my bike and starting my ride, when I come to my first stop, it feels like I don’t have any brakes. The brakes are very spongy. After coming to a complete stop, my warning light and brake failure light start flashing. But as I pull in the front brake I can hear the ABS and the caliper working. And suddenly the brakes seem to be fine. But I still have the blinking warning lights. I scratch my head.
This needed someone with much more knowledge than me. So off to Velocity Cycle I go to have Master BMW Mechanic Chris look at it. He pulls in the bike and starts taking her apart while I go sit on the BMW R1200R and the R1200GS. Finally he calls me back and asks what I did to it! I told him I just ride it. He looks at me and laughs and makes fun of me because the bike is 8 years old and only has 13,500 miles on it. Anyways, he points out the problem. The ABS pressure modulator was leaking brake fluid. So when I pull on the front brake, brake fluid would slowly leak out the top of the ABS pressure modulator. My bike also has partially linked brakes so when I pull on the front brake, the back brake also engages. And the speedometer is also connected through the ABS system. So since there was a leak and pressure wasn’t constant, this probably caused the speedometer to act up.
So I need to replace the ABS pressure modulator. Cost for new unit? $2,500. Ouch! But there’s alternatives. I could remove the ABS, run new stainless steel braided brake lines like Spiegler and save 14 pounds of weight. But this may hurt the re-sale value of the bike, and may cause issues because the speedometer is linked through the ABS. Or I can find a used ABS pressure modulator and pretty much plug and play. After much discussion I went with finding a used ABS pressure modulator. First place I checked was BeemerBoneyard which did not have any in stock. I also checked a local guy named Curci who buys up tons of wrecked BMW bikes. He didn’t have one. Finally I posted a parts wanted ad on ibmwr.org (same site I sold my BMW F650GS through and found/bought my BMW R1100S). The following day I received a call from Phil Cochran from Phoenix, Arizona. He had the part I needed off of a 2004 model and for $599 (shipped). This is MUCH less than $2,500. It should be shipping out tomorrow. Hopefully the rest of the fix goes smoothly. I’m having withdraw from riding!
