R1150RT Servo problems

[Humbug]

I hope someone can help with this.

My friends 2004 R1150RT has the following brake symptoms:-

The front brake works fine, the servo's operate as normal.

Th rear brake worked fine if light pressure was applied to the pedal and the servo's worked fine. However if heavy pressure was applied, the servo's failed completely and he only had residual braking. The front's failed also. If he stopped and reset the servo's returned. He was able to ride with good brakes so long as the rear was not used heavily.

He took it the local BM dealer and they declared the ABS unit was u/s and it would cost £1800 for a replacement! About half the value of the bike! They did play about with the rear brake switch and now there are no rear brakes with servos whatsoever. The front 's work perfectly.

We've tried Steptoes filter clean but this has made no difference. The filters were very clean - the bike has only done 6,000 miles since new! On applying the rear brake a faint clicking can be heard in the servo unit - almost as if it is trying to switch the servos on?

Before we carry out a complete servoectomy can anybody confirm that this is the usual way they fail or is there something else we should be looking at? It seems strange that the servo's work fine from the front but not the rear?

Any pointers or help would be greatly appreciated.

 

[DrFarkoff]

search

Link to remove the system HERE or somewhere in the vast wilderness of this site there is a take apart and clean servo thing from Steptoe

 

[Myke Rocks]

Check her for a replacement

mikemedic
of this parish is selling one.
http://www.ukgser.com/forums/showthread.php?t=265253

Give him a call.

Myke

 

[Humbug]

Gets stranger this one

We thought we'd check the brake light switch even though it appears to function perfectly well. Got it off and gave it a good dousing with WD40. As we were moving it around we heard the servo's whine a couple of times, similar to when you first switch on an the system carries out the brake test! This we were able to repeat but not always. We reassembled the rear brake plate but left the switch free. Ignition on, brake check, ABS light flashing at 4 cycle per second, apply front brake, servos work. Keep front brake lever in, then apply rear brake hard and hold rear brake switch on, servos could be heard increasing in pressure. Let front brakes off but keep rear brake depressed with switch still on, servos still working! Release brake switch and servos stopped.

What is happening? A new brake switch is on order. Could this really be the problem?

 

[Twotter]

No idea, but it's a good tip for the future

 

[DrFarkoff]

One tip NEVER use WD40 on rubber bits like switches etc especially R1200 handlebar stuff

The cheap rubber they use for seals swells and splits and does all sorts of funny things!

ACF on the connections and a drip or two on the pinion with 3 in one or something similar

 

[DollyRocket]

Virtually identical fault with mine last week. Rear brake would shut the servo down if you touched the pedal. Error code was ' too high pressure in rear circuit'. Which is technical for 'fooked'.

Steptoe ripped it out last week. New pads in the front and it is pretty good. Back wheel locks up and has 'substantially' more braking force than previously (even with steptoe). I quite enjoy stopping at lights sideways now

 

[Humbug]

My pal couldn't be arsed waitng about for a new rear brake switch so this afternoon we junked the servo in accordance with the excellent instructions that Steptoe kindly supplied a link to in an earlier thread (the same link Jaythro gave in a post above). Total cost was £40 for a new braided rear hose and brake fluid. My friend reports that the brakes are superb and he's really happy.

Many thanks for all the words of advice.