Rear brake servo failure

Motocod · Post by **Motocod** » Sat Mar 01, 2014 5:39 pm

Hi Folks,

As it says above, I've lost servo on my rear brake. The brake still works, albeit you've got to really stand on it! I've got two flashing warning lights on the dash. Front brake is fine.

After leaving the bike and coming back after 15 mins the problem went away, and then promptly came back again after a few minutes riding.

I've no idea where to start, so any advice would be appreciated!

Thanks,

Nik

Phil K · Post by **Phil K** » Sun Mar 02, 2014 6:47 pm

Check rear brake light bulb

Motocod · Post by **Motocod** » Sun Mar 02, 2014 11:01 pm

Really?!

Motocod · Post by **Motocod** » Mon Mar 03, 2014 10:39 am

No ideas then people? Has anyone else experienced servo failures? Just curious to know how the system works, such that it would fail only on one end of the bike. Seems kind of strange - surely it's the same servo for both sets of brakes?

Nik

ned1 · Post by **ned1** » Mon Mar 03, 2014 11:29 am

Hi,
There are four circuits (on my old R1100s 03 anyway) which are..........
Front hand brake lever to servo unit, control circuit
then a separate circuit from the servo unit to front calliper and the same for the back.
Have you checked the brake fluid levels in the servo unit which is under the tank.

Hope this helps

Ned

Motocod · Post by **Motocod** » Mon Mar 03, 2014 12:57 pm

Thanks Ned. Not checked fluid levels - will that require bodywork removal?

Also read elsewhere that the issue could be due to the rear level not returning fully back to its stop, so I'll check that.

ned1 · Post by **ned1** » Mon Mar 03, 2014 2:42 pm

Motocod,

The servo is under the tank, so its bodywork and tank.
If you let me have your email via PM I will try and send you the
information I have on bleeding the ABS brakes which also has lots
of photos so you will be able get get an good idea whats it all about.

Ned

Motocod · Post by **Motocod** » Mon Mar 03, 2014 2:55 pm

Thanks Ned, PM sent.

In the meantime I'll check the fluid levels, and dig the Haynes out...

Nik

Phil Thomas · Post by **Phil Thomas** » Mon Mar 03, 2014 5:23 pm

Motocod wrote:Hi Folks,

As it says above, I've lost servo on my rear brake. The brake still works, albeit you've got to really stand on it! I've got two flashing warning lights on the dash. Front brake is fine.

After leaving the bike and coming back after 15 mins the problem went away, and then promptly came back again after a few minutes riding.

I've no idea where to start, so any advice would be appreciated!

Thanks,

Nik

I had exactly the same problem with my R1150RS (which actually had linked brakes from the front brake lever). It turned out to be the rear servo pump and was fixed under warranty by North Oxford Garage. It appears that it was a common problem, so maybe it was a batch problem. After it was fixed I had no problems...I hated the servo system!!!

Regards to all,

nab 301 · Post by **nab 301** » Tue Mar 04, 2014 11:56 am

Motocod wrote:Hi Folks,

As it says above, I've lost servo on my rear brake. The brake still works, albeit you've got to really stand on it! I've got two flashing warning lights on the dash. Front brake is fine.

Nik

I don't have an i abs bike but what sequence are the lights flashing in?
This thread has a link to follow
viewtopic.php?t=17583&start=0

i ABS link in this http://www.largiader.com/abs/absfault.html

Motocod · Post by **Motocod** » Wed Mar 05, 2014 1:12 pm

Thank you Nigel - some interesting information there, that's really appreciated.

To be honest I need to find the time to have a good look over the bike and see if there are any obvious physical defects. Although that's extremely unlikely, as the bike has probably done less than 200 miles since the start of December (I absolutely will not ride it on salty roads, it's too nice!).

Had a quick look this morning and rear level returns to stop correctly. So I guess I need to check the rear pads and see if they're low, check the rear fluid (is that under the tank?), and then I suppose I will reluctantly have to take the bodywork off and check servo hoses etc.

Slightly miffed doesn't come close - I decided on a BMW to replace a frightful Multistrada that ate up way too much time with stupid problems exactly like this. Hey ho, here's hoping it turns out to be something simple.

Nik

Motocod · Post by **Motocod** » Wed Apr 02, 2014 2:21 pm

Hello folks,

Quick follow-up on this - just spoken with a technical chap at Bahnstormer (my nearest dealer) and they've suggested either the dreaded ABS pump (through lack of use of the winter), or possibly the rear wheel speed sensor, which could be due to emulsified oil in the rear hub assembly. Does anyone have any experience with the later?

I'm going to go and give the bike a run now to see where it's at. Might be that it just needs a bloody good thrash to get it all nice and warm and cleared out!!

Nik

The Teutonic Tangerine · Wed Apr 02, 2014 2:49 pm

Is there a micros switch on the brake pedal similar to the one on the Brake lever? Maybe its got crudded up.

andy griff · Post by **andy griff** » Wed Apr 02, 2014 2:52 pm

Nik,

sorry to hear of a potential fault with the bike. Good luck with the 'thrash' idea.
It will be very bad luck to have a pump go at 10,000 miles- fingers crossed for you

Andy

Motocod · Post by **Motocod** » Wed Apr 02, 2014 8:29 pm

The Teutonic Tangerine wrote:Is there a micros switch on the brake pedal similar to the one on the Brake lever? Maybe its got crudded up.

Will check that tomorrow, thanks.

www.boxertrix.com

Rear brake servo failure

Rear brake servo failure

Re: Rear brake servo failure

Re: Rear brake servo failure

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