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Discussion Starter #1
Just home from from a short ride. Came down from highway speed and felt the rear brake was dragging. Managed to nurse it home a couple of miles and found brake lights were on. Parked bike and shut off. Left for a bit and found that front was good and nothing at all now at back. ABS seems to cycle when key turns on and when I do the forward motion light goes out as it's supposed to but still no back brake now. Suggestions or ideas? 2002 1200LT. 46,000 miles. Just bought it and is my first BMW bike. Help if you can. Thanks.
 

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Sounds like a similar situation I had with my 2000 LT. I had adjusted the rear brake lever while the LT was on the center stand and cold (engine not run) so that the rear brake pads were just not touching the rotor when I rotated the rear tire when in neutral gear (I wanted less play in the rear brake lever). When I test drove the LT right after the adjustment the rear brake started to grab about a few miles out without any pressure on the rear brake lever from me. I stopped and to my surprise the rear brake line was on fire due to a cherry red rear brake rotor. I put the fire out and had the LT repaired. What I surmise happened (not really sure) was that the rear brake line fluid expanded due to the heat generated from the final drive causing the brake pads to exert force against the rotor. Members of this forum suggested that the rear brake lever adjustment should have adequate play in order to prevent this situation from happening. Bottom line, check your adjustment, previous owner may have adjusted it too tightly. There are other possibilities, I am sure other members will comment. (see photo of fire damage)
 

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OK the 2002 has a different brake system than the one just described by Captain Wayne (although your situation could be caused by faulty brake lines). It is a linked servo ABS system. Here is how it works:

Key on the servo system does a self check (you hear it whining) and the lights flash fast. This will complete in a few seconds IF you don't hold a brake on, other wise it will continue until you release the brake. Then after completing that test it goes to s slow flash until the rolling test is completed (drive a few feet). The rolling test checks the wheel speed sensors for the ABS.

Now during normal operation you can apply the brakes with the lever on the bars or the pedal and BOTH front and rear will operate as they are linked. You cannot apply just front or just rear on this bike as the ABS unit will activate both proportionally.

Now to get to your issue, here is a test I want you to perform. Put the bike on the center stand and turn on the key but don't start the bike and let it transition to the slow flash state. Apply the lever brake lightly and listen for the whine and release. Did the whine go away? If so then press the brake pedal and listen for a whine and release. Did you get a whine and did it go away?

If the answer was not yes to both turn off the key and listen to the lever as you pull it, you should hear a slight click as the the switch in side engages. Now go to the pedal and listen for a click as you press the pedal. If you don't get a click at both then the switches are out of adjustment or faulty.
 
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OK the 2002 has a different brake system than the one just described by Captain Wayne (although your situation could be caused by faulty brake lines). It is a linked servo ABS system. Here is how it works:

Key on the servo system does a self check (you hear it whining) and the lights flash fast. This will complete in a few seconds IF you don't hold a brake on, other wise it will continue until you release the brake. Then after completing that test it goes to s slow flash until the rolling test is completed (drive a few feet). The rolling test checks the wheel speed sensors for the ABS.

Now during normal operation you can apply the brakes with the lever on the bars or the pedal and BOTH front and rear will operate as they are linked. You cannot apply just front or just rear on this bike as the ABS unit will activate both proportionally.

Now to get to your issue, here is a test I want you to perform. Put the bike on the center stand and turn on the key but don't start the bike and let it transition to the slow flash state. Apply the lever brake lightly and listen for the whine and release. Did the whine go away? If so then press the brake pedal and listen for a whine and release. Did you get a whine and did it go away?

If the answer was not yes to both turn off the key and listen to the lever as you pull it, you should hear a slight click as the the switch in side engages. Now go to the pedal and listen for a click as you press the pedal. If you don't get a click at both then the switches are out of adjustment or faulty.
Hey John. Did the test and the whine engaged and released on both lever and pedal. The sound was a little different on the pedal but did stop as soon as I released. Also did the second test as well and there was a click on both lever and pedal. I did just purchase this bike last week and the previous owner had just replaced the rear main seal and a friction disk. He seems to be very particular with his equipment and I trusted his ability. Not sure if that information was or is relevant but I thought I should share.
Scott
 

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Sounds like everything is OK. The rear brake pedal should stop the bike as well as the front brake lever but you really have to press it hard. You may have some air in the integral passage on the ABS as the sound should be the same on both presses. Try pushing harder on the pedal and see if you can get it to sound the same.
 
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... and nothing at all now at back..
This doesn't sound ok.
Have the brake flex hoses been replaced? Common upgrade is to replace them with braided stainless steel hoses. Those would be obvious. Not sure what caused the dragging brake, but no braking can be a busted hose.
For some reason, this bike eats rubber brake lines.
 

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Discussion Starter #7
Brake lines are still rubber but appear to be in good condition. There is fluid in forward and aft compartments. I have been reading up about swapping out the hoses and I should look into that. Might be a little over my paygrade though. Not afraid to tackle the job, just not sure if I am accurately tooled.
 

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They may look good visually but the usual mode of failure is for the lining to de laminate and act as a check valve. Tends to lock caliper up so may indeed not be your problem. They are old and do need to be changed out. There are Spiegler kits with all the parts available.
 

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SO, with a little further investigation, I found that I have front and back brake with the lever but nothing with the pedal. The pedal does make a clicking sound when I depress it with the key off. When key on, the pedal does actuate the ABS. At least I have both brakes on the lever but I'm still at a loss as to no rear with the pedal.
 

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Brake lines are still rubber but appear to be in good condition. There is fluid in forward and aft compartments. I have been reading up about swapping out the hoses and I should look into that. Might be a little over my paygrade though. Not afraid to tackle the job, just not sure if I am accurately tooled.
I felt the same as you last year but tackled the job easily with the help of Kirk's video. Just do it, to coin a phrase.
 

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I felt the same as you last year but tackled the job easily with the help of Kirk's video. Just do it, to coin a phrase.
Kirk's video? Just found that - very helpful.
 

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SO, with a little further investigation, I found that I have front and back brake with the lever but nothing with the pedal. The pedal does make a clicking sound when I depress it with the key off. When key on, the pedal does actuate the ABS. At least I have both brakes on the lever but I'm still at a loss as to no rear with the pedal.
Ok the ABS servos get input from both the brake switch and pressure, sound like you are missing pressure. This could be a collapsed line as mentioned OR the rear master cylinder push rod is adjusted too tight. You can remove that foot plate and see if there is some slack or free play on the rod going into the master cylinder.
 

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