Worn brake pads?

[tazplas]

When i got home the other week after a small trip, i got to the top of the driveway and stopped. I noticed the the brake light and the general warning light started alternatively flashing. Brakes still functioned. Annoying squealing noise as per standard when brakes applied and stopped ok. Good thing really as the garage door was shut at the time. Anyways, shut down bike and then restarted. All systems ok. Went for a ride the over the next few weeks and no problems to report. Last weekend, riding into town through peak hour and using the brakes quite a bit, same problem reoccurred. Brakes functioning ok so i continued on home for the next 20kms. Shut down bike and then restart. All systems ok.

 

My little BMW Rider manual tells me that the fault(flashing lights) = Fluid level in the BMW Integral ABS is too low. Checked all round bike. No leaks!TGFT. All reservoirs seem to be at the correct level although i must admit the rear unit is pretty hard to make out.

My thoughts - can this fault occur if the brake pads are getting worn and are near their limit?

Or are other forces at work here?

 

Help much appreciated

 

 

Steve

[T__]

When i got home the other week after a small trip, i got to the top of the driveway and stopped. I noticed the the brake light and the general warning light started alternatively flashing. Brakes still functioned. Annoying squealing noise as per standard when brakes applied and stopped ok. Good thing really as the garage door was shut at the time. Anyways, shut down bike and then restarted. All systems ok. Went for a ride the over the next few weeks and no problems to report. Last weekend, riding into town through peak hour and using the brakes quite a bit, same problem reoccurred. Brakes functioning ok so i continued on home for the next 20kms. Shut down bike and then restart. All systems ok.

 

My little BMW Rider manual tells me that the fault(flashing lights) = Fluid level in the BMW Integral ABS is too low. Checked all round bike. No leaks!TGFT. All reservoirs seem to be at the correct level although i must admit the rear unit is pretty hard to make out.

My thoughts - can this fault occur if the brake pads are getting worn and are near their limit?

Or are other forces at work here?

 

Help much appreciated

 

 

Steve

 

 

Steve, did you remove the fuel tank & check the brake fluid level in the ABS controller? That is the fluid level the manual is talking about not the front or rear master cylinder levels.. (the wheel side master cylinders are in the ABS controller itself)..

 

(Yes), as the brake pads wear they can lower the fluid level in the controller master cylinders.. Usually the full system bleed is done often enough to keep up with the pad wear..

 

If the bike has ever been tipped over on it’s side that can allow some brake fluid to escape the controller master cylinders..

 

 

Twisty

 

[tazplas]

Thanks Twisty.

 

No i haven't check the level in the ABS controller. I suppose that's next.

And as far i as i know, the bike has never been tipped over, at least not by me (hope i haven't tempted fate here, touch wood.

 

It may well be that i am due for flush and brake pads change. Something to look into i think.

 

Many thanks

 

Steve

[flyingreg]

With an intermittent problem like you are describing, you should check your battery voltage. A weak battery that is in need of replacement can still give enough juice to start the bike, but not have enough voltage to properly operate the brake servo motors, hence the fault warning you are receiving. Considering you are riding short distances does not allow the battery to fully charge.

 

Check this condition out and report back your findings. And if you are not familiar with the systems and/or don't have the tools and equipment to properly diagnose, take it to the dealer for diagnosis.

[tazplas]

Another good idea.

 

I do notice that it takes a few cranks to fire when its cold versus after i have a good run at things.

I work for a company that installs solar panels, battery banks etc so yes i do have access to load testing equipment. Will look into that possiblity as well.

 

Cheers

 

Steve

[tazplas]

New information

 

I only get the fault lights conming on after i have used the rear brake.

Would there be a specific reason?

Is the rear system separate from the front?

Common fluid?

 

Turning the bike off and restarting resets the fault back to normal.

 

Will probably start the investigation in a week or 2

 

Cheers

 

Steve

[T__]

Steve,

I only get the fault lights conming on after i have used the rear brake.

Would there be a specific reason?….. Nothing specific but on the BMW Oil Head the rear brake pads seems to wear much faster than the front pads do.. But the fluid displacement is per mm of wear is less due to smaller caliper piston volume.. Maybe make sure the rear servo motor is shutting down when you release the brake pedal as the rear pedal or rear switch is subject to more dirt & road crap than the front lever switch & cylinder..

 

Is the rear system separate from the front?

Common fluid?….. Yes, the front & rear are separate systems with separate reservoirs in the ABS controller.. There is an interconnection between ft & rear but no actual fluid exchange..

 

 

Turning the bike off and restarting resets the fault back to normal….. That is a normal trait on the IABS system as it will re-set on power down/power up after the fault goes away or returns to normal..

 

 

Will probably start the investigation in a week or 2….. If nothing can be found ride by the local BMW dealer with the fault light flashing & have them pull the IABS controller fault codes (should point to the problem)

 

 

Twisty

 

 

[Ron L]

...on the BMW Oil Head the rear brake pads seems to wear much faster than the front pads do

 

Really? I'm on my 3rd set of front pads and second set of front rotors and just put my first set of rear pads on my R1100RS. I think maybe this has to do more with braking habits and riding style than a Oil Head trait, but maybe the servo brake bikes are different

Ron L

[AndyS]

...Really? ... I think maybe this has to do more with braking habits and riding style than a Oil Head trait,.... but maybe the servo brake bikes are different

Ron L

 

Hi Ron, Yes Twisty is right on the money for the 1150RT. I believe the servo is the reason. However that doesn't make it a problem. It is just the way it is. I am really happy with my brake balance (even though some others aren't... something about not pleasing all the people all the time, I think!)

 

Andy

[tazplas]

Thanks Twisty

I will check the pedals etc and see what is what.

 

Cheers

 

Steve

 

[Stan Walker]

Can't prove it by either of my RT's. Both are still on their original rear pads. 74,000 on the '96 1100, 108,000 on the '02 1150.

 

Stan

[AndyS]

Can't prove it by either of my RT's. Both are still on their original rear pads. 74,000 on the '96 1100, 108,000 on the '02 1150.

 

Stan

 

Hi Stan.

Your experience is something I am envious of, but I think it is true to say that for nearly everyone else, your results are very much the exception to the rule.

None the less I am glad you do get such astonishing results.

 

Andy

[knight88]

Can't prove it by either of my RT's. Both are still on their original rear pads. 74,000 on the '96 1100, 108,000 on the '02 1150.

 

Stan

 

I too have replaced my front pads twice but not the rear pads yet, it seems that I wear out the front more than the rear. (02' 1150RTP)