Scared the S&%T out of me

[knight_vision4u]

So I was cruising back home this afternoon from town and about eight miles from the house the (infamous) ABS General Warning light came on. I'm in the middle of lunch hour traffic and not able to pull to the side of the road to stop and check it out. So I continue to the police department parking lot (as I am a cop) pull into the parking lot grab the clutch, (When the engine noise subsides I can hear the ABS pump running), and the bike stops with out me having to use the brakes.(Now I have had problems with it in the past but nothing like this.) So I do what I have to do at the PD (probably 15 minutes), jump on the bike, every thing is good the general ABS light is out, I turn on to the highway go about a mile, and the go to apply the front brake lever and the front wheel locks up, I'm talkin' full on locked up. Im not going very fast but but fast enough to leave about five feet of rubber on the road. So I manhandle the bike, with both front and rear wheels locked, off the roadway and on to the shoulder. After regaining my composure I call a tow truck and begin to look at the bike. The rear brake disk is blue and the top vertical edge is now gold colored so that tells me it was rather warm and there was a white powder in the brake disk holes(?). One of the tow truck drivers recommends opening the bleeder valve on the rear caliper to (possibly) relieve the pressure and release the pads, so I do, and there is no fluid in the caliper. The wheels are still locked so the tow truck driver has to use the winch to drag the bike on the flat bed and he takes it home for me.
The brakes were serviced about three weeks ago and the fluid was changed.

[JimVonBaden1]

which bike?

Jim :brow

[knight_vision4u]

2004 R150rt

[brrider]

:type Good job manhandling it. I was happy to here that it was a happy ending. I would raise some hell and the shop that did the brakes.

Keep us updated and I am glad you are OK

[Motor31]

Who serviced the brakes?

[derail412]

Something similar happened to a friend of mine. He had brake work done on his bike and instead of adding DOT 4 brake fluid he added DOT 5 fluid. His brakes seized shortly there after. You may want to check with the shop that did your repair.

D

[knight_vision4u]

Just got the bike back from the mechanic (Basin Motorcycle Works:D ) today.
Harry replaced the "micro switches" on the rear brake foot lever, and the front brake lever and presto its fixed. He had to do a little reasearch but he found that the switches got "super sensitive" and the ABS unit couldnt react fast enough to the signals the switches were sending, so it thought the switches were closed all the time (sending a signal to the ABS unit), thus sending pressure to the calipers, causing the brake pads to come in contact with the rotors just enough to heat the pads up which caused them to swell. Then when I used the front brake lever, it was just enough pressure to lock both front and rear brakes up and ABS unit could not prevent the lockup. So Harry tore the rear brake caliper apart found that it was salvageable, put new pads on it checked the front pads (they were ok) and five hundred dollars later I'm back on my Beemer. I know this is confusing, but it kinda makes sense. The ABS general warning light did not come on, on the ride home so I'm hoping this will fix that problem too. A big thanks to Harry Hill and his gang at Basin Motorcycle Works. It was very difficult to be with out the bike as we only have one cage (FJ Cruiser) but the Beemer is fixed and I'm thrilled.

[skidgillen]

Your problem has got me worried now. See my thread on "Brake Failure" light, which I haven't resolved yet, and I'm not looking forward to a dealer $ervice bill. I did notice the other night when I was having problems, and had it on the centerstand, I hit the rear brake and the servo stayed stuck on until I hit the rear brake again. I'll have to look at my microswitches closely. Stay safe and stay on the Thin Blue Line.:brow

[awagnon]

Just got the bike back from the mechanic (Basin Motorcycle Works:D ) today.
Harry replaced the "micro switches" on the rear brake foot lever, and the front brake lever and presto its fixed. He had to do a little reasearch but he found that the switches got "super sensitive" and the ABS unit couldnt react fast enough to the signals the switches were sending, so it thought the switches were closed all the time (sending a signal to the ABS unit), thus sending pressure to the calipers, causing the brake pads to come in contact with the rotors just enough to heat the pads up which caused them to swell.

I'm sorry, but I'm very dubious of this explanation. I don't believe that's how the brakes work. I still bet the brakes were screwed up on the service three weeks prior. Too much of a coincidence.

[GrafikFeat]

I'm sorry, but I'm very dubious of this explanation. I don't believe that's how the brakes work. I still bet the brakes were screwed up on the service three weeks prior. Too much of a coincidence.

I agree... "Just enough pressure" so as to swell. Just enough to lock up? Nah.
You'd feel the dragging. Your rotors discolored? Thats some heat!
Sounds like shop double speak...

Have him check the wobulater and the external decapitator as well.

Then find a new wrench.

[Motor31]

The explanation doesn't seem very plausible to me either. Are there any indications of heat on the rotors? Enough heat to make the pads "swell"?????? Since the pads were designed with heat in mind I find it hard to believe that they would "swell" from that. Getting soaked in brake fluid maybe would degrade them but not make them swell.

[BONEY]

I noticed, after off roading a bit on the RT that my rear lever wasn't returning to full up position. This was causing the servos to run all the time and slight brake pressure to the calipers.

Luckily, I didn't go far before I noticed "something" was up.

It is imparative that the levers return to full "up" and open the micro switch contacts on these bikes. It should be included in every pre-flight inspection, and is easy to do- the switches click loudly when they operate.

[Andy VH]

There are no "micro-switches" in the brake system that send signals to the ABS modulator. There can be a micro-switch that actuates at the rear brake pedal to turn on the brake light, and there is a hydraulic actuated switch in the master cylinder of the front brake to operate the brake light.

Neither of those switches do anything to actuate the ABS system. The ABS system has wheel speed sensors that constantly read wheel speed whether you are on the brake or off the brakes. If either wheel, ONLY when braking is applied, slows enough to lock up, then the ABS engages and modulates that brake back up to match the actual bike speed.

Now, what happened on your bike is FAR from normal and something is definitely wrong. But it has nothing to do with micro-switches. I also doubt it would have anything to do with DOT 3 brake fluid versus DOT 4 brake fluid. DOT 3 is glycol based brake fluid, DOT 4 is borate based brake fluid. DOT 4 has a higher boiling point than does DOT 3. DOT 5 fluid on the other hand, if put into a system set up for DOT 3 or DOT 4 WILL cause all sorts of brake problems, the most common being a dragging brake creating tons of heat! I know that from first hand experience. DOT 5.1 though is another glycol or borate based fluid. So to play it safe, if your system calls for DOT4 then it should have that.

Here's some good info on brake fluids: http://www.afcoracing.com/tech_pages/fluid.shtml

[awagnon]

I believe that when the micro switch is closed, it does activate the servo assist, but should not apply brake pressure. Maybe if it was left in the closed position for some time. Also, you should have heard the servo assist pump whining all the time when it shouldn't if that was the case.

I still think that it is more than a coincidence that the brakes failed relatively soon after being serviced. I gotta believe there is a connection.

[knight_vision4u]

As I explained in the original post the brake rotor is a gold/blue color and the ABS pump was running prior to the "incident". The rear brake pads had been glazed so there was a fair ammount of heat there. It makes sense if the switches were faulty they might be sending a signal to the pump to turn on. Not saying you guys are wrong just telling you what I was told. Im just happy its working (properly) again. Thank you for all the ideas and I will keep you posted if any problems arise.

LOVE the MOA!