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spudpuppy
05-13-2007, 12:06 PM
I have a 2005 1200 RT. The front hand brake application has always been a concern for me since I purchased the bike. When I grab the lever I feel vibration and almost what I would describe as shuttering. My dealer volunteered to take it for a test ride if I brought it by. When the tech returned from the test ride, he said that was normal and it had something to do with the ABS "pulsing" the system. I find this explanation unusual for two reasons. 1. When I apply the back brake only, it's very smooth. 2. My brother has a K bike with ABS that's very smooth all around. I have 8000 miles on it, the front wheel has never been off the bike. Any advice out there from someone with the same experience? Is this normal?

Only other complaint is that my mileage is too low!! Great Bike!

Thanks

easy
05-13-2007, 01:41 PM
You say you feel vibration when ÔÇ£grabbingÔÇØ the brake lever. If the vibration is prevalent without activating the brake but just touching or grabbing the lever, you may have a problem with the brake disc. It could be warped. If the vibration is present by using the front break without using it hard enough to activate the ABS system, then you probably have a problem with the ABS.

Under normal braking, without activating the ABS system, there should be no pulsing in the system.

At any rate, it is not normal. I would suggest finding another tech, one that has not inhaled quite so many exhaust fumes. :hungover

Also make sure you keep a copy of the paperwork. If the brakes fail and you have an accident, you have some evidence.

Easy :german

roborider
05-13-2007, 02:15 PM
I have the 05 R12RT. I'm assuming you are not 'grabbing' the brake lever in a panic stop. For example, you say the rear brake is smooth. Try going 20 mph and and applying the rear brake only very hard. You will start to skid and then the ABS will take over and pulse you to a stop. This give you the 'normal' pulsing sensation of ABS and really you would not expect to feel it under normal riding.

The front brake (which is of course both brakes) is grabby in that it can be tricky to use at slow speed (say 10 mph and lower in a parking lot). I tend to use the rear only at these slow speed maneuvering conditions. Other than that, say stopping from 40 mph coming to a red light, the brakes should be very smooth, no pulsing, no grabbing. Just ride another RT and you should see the difference (don't let the dealer tell you it was a newer RT with the non booster pump brakes-the booster pump on the 05 still is smooth).

Possible problems I can think of, some mentioned:

ABS problem (initiating too soon)
Bent rotor
Grease or dirt on the brake pads (replace)

In any case, it is ABSOLUTELY NOT NORMAL FOR THE RT TO STOP WITH A JERKY FEEL. It stops very smoothly and quickly.

Get it fixed, it's still under warranty.

Robo

spudpuppy
05-14-2007, 02:06 AM
I should have mentioned that my problem was under normal braking, when the lever is applied, for example, coming down from highway speeds. I typically will start with the back brake and bring in the hand lever as needed.

Thanks for the input. I will have it checked out at another BMW dealership.

maxfrankel
05-14-2007, 01:57 PM
You mentioned you typically start with your back brake and use the front as needed. In my MC safety courses, emphasis was always placed on using the front brake for that's where the braking power really rests. With the R12RT integrated front brake, IMHO, virtually all braking should be done with the front brake (except very low speed and sand circumstances) since the front brake engages both front and rear. Reflexive reliance on the rear brake is likely to cost you dearly in a panic stop situation and less importantly, put additional disproportionate and unnecessary wear on your rear tire.

roborider
05-14-2007, 06:27 PM
You mentioned you typically start with your back brake and use the front as needed. In my MC safety courses, emphasis was always placed on using the front brake for that's where the braking power really rests. With the R12RT integrated front brake, IMHO, virtually all braking should be done with the front brake (except very low speed and sand circumstances) since the front brake engages both front and rear. Reflexive reliance on the rear brake is likely to cost you dearly in a panic stop situation and less importantly, put additional disproportionate and unnecessary wear on your rear tire.

I agree. The 'front' brake engages both brakes appropriately as needed with ABS in mind. There is no reason to engage the rear brake separately but as mentioned I use it in low speed manuevering situations.

Motorwerk
05-15-2007, 05:04 PM
This is a known issue caused by the wheel resulting in warped rotors. It was prevelant on the early '05 models. Not sure when it was addressed.

The ABS has nothing to do with the problem. Dealers were replacing rotors only to have them come back for the same issue.

Get to the dealer and impress upon them to look into the matter. I'm sure there is a service bulletin out there on it somewhere.

spudpuppy
05-16-2007, 01:51 AM
This is a known issue caused by the wheel resulting in warped rotors. It was prevelant on the early '05 models. Not sure when it was addressed.

The ABS has nothing to do with the problem. Dealers were replacing rotors only to have them come back for the same issue.

Get to the dealer and impress upon them to look into the matter. I'm sure there is a service bulletin out there on it somewhere.

Thanks for the info, I have made an appointment to have it checked out next week. I'll post the results.

spudpuppy
06-05-2007, 03:38 AM
Picked the bike from the dealer today with new rotors and just returned from a nice ride to test. It's now obvious to me that I never had the brake feel this bike is supposed to have from the beginning. Very smooth and predictable.

Had the dealer install a new set of Z6s while I waited for the rotors to arrive and all is well! :wave

Motorwerk
06-05-2007, 04:53 PM
That's good news.

What exactly did they replace?

If it was only the rotors I would be leery that this may happen again.

spudpuppy
06-07-2007, 11:58 AM
They replaced the rotors only. The dealer claims there are no bulletins on this situation from BMW.

I am a bit concerned, yet I have very smooth braking which I never had since this bike was new.

Since I purchased in early 06, I will hope that warranty and history would apply if the problem is not fixed long term and/or becomes inherent to this model.