Stuck rear brake

[tonycum]

I had my 2013 GS serviced 29 miles ago at 18,500 miles
It had a new disc and pads fitted (I was unaware there was a problem - seemed to work fine to me - but hey, what can you do - they told me it had to be done?). I was told that the calliper was corroded but balked at the cost I was quoted for a replacement. The BMW service centre 'cleaned up' the calliper and refitted it. A few days and 9 miles later my rear wheel locked after about 100m of travel from home. The rear brake was locked solid. I removed the calliper and limped home. Thinking it was a matter of 'I told you so' regarding the calliper, I chose not to return it to BMW but instead I sent it off for refurbishment to Powerhouse Automotive in Chesterfield.They said that there didn't seem to be anything wrong with it but I had it refurbished anyway.
I got it back and refitted it and bled the brake line.
Seemed fine when I drove it 8 miles for its MOT - sailed through and brought it home. Lockdown kicked in and it sat in the garage until a few days ago when I took it out - and the rear wheel locked again.Problem solved by backing off the bleed valve and releasing the pressure.
I now find that the wheel will spin freely until I put the ignition on. If I don't use the rear brake at all, but press the front brake lever, within moments the rear brake is solid once more.
I'm thinking this must be an ABS problem. Has anyone got an ideas and preferably a solution which won't cost me £££££ at BMW again?

 

[spoonz]

Odd one

Has anyone adjusted the free play at the rear brake pedal ? If there is insufficient play the return port in the mc remains covered by the piston as it cannot retract fully and prevents the return of fluid.

As the brakes are linked using the front brake is also applying the rear a bit so maybe that could be the link.

 

[Rockred]

That doesn't seem right somehow, it should not need a new disc after only 18,000 miles, there must be some thing else going on, I don't know what, but I'm sure someone will be along shortly that will have a better understanding of your problem. As for only applying the front brake, because the GS has a linked braking system, so every time you apply the front brake the rear brake will be automatically applied.

 

[tanneman]

It may be that your return is blocked.

 

[roamer]

As mentioned allready,
It may be worth checking the rear brake master cylinder piston is returning fully,
That would hold pressure in the rear brake,

 

[Mr Bean]

Has anyone adjusted the free play at the rear brake pedal ? If there is insufficient play the return port in the mc remains covered by the piston as it cannot retract fully and prevents the return of fluid.

I made the mistake of 'adjusting' the free play on my old 2013 bike as the pedal had loads of movement in it. Even though there was no pressure on the master cylinder whilst stationary, during a ride the brake would bind to the point of locking up - I backed it off in stages, until I was back where it started...

 

[OldSteve]

I made the mistake of 'adjusting' the free play on my old 2013 bike as the pedal had loads of movement in it. Even though there was no pressure on the master cylinder whilst stationary, during a ride the brake would bind to the point of locking up - I backed it off in stages, until I was back where it started...

Yes - been there, done that as well to "remove" a lot of free play on a non-GS BMW. End result was new disk and pads and same amount of free play.

 

[tonycum]

I didn't know that front and rear were linked. This makes more sense now.
I think I'll try sending the ABS unit to controlunits.co.uk
They quote £185 + VAT for repair. Sounds a lot cheaper than BMW and it sounds like where my problem lies.

 

[Alan R]

]I didn't know that front and rear were linked. [/B]This makes more sense now.

You are very honest to say that. It is however quite a basic feature that you should really know about your bike. Have a read of the manual and it will explain how the linking is set up. You may also find other features of which you weren’t aware.
Alan R

 

[jetjock]

My 2017 GS needs yearly maintenance to free up the rear brake lever bolt . If I don’t do this the brake over sticks in the on position . If I use it !!

 

[Woollards]

Hi Tony, my bike has just developed the same fault. Did you get to the bottom of the proble? Thanks John

 

[Woollards]

I had my 2013 GS serviced 29 miles ago at 18,500 miles
It had a new disc and pads fitted (I was unaware there was a problem - seemed to work fine to me - but hey, what can you do - they told me it had to be done?). I was told that the calliper was corroded but balked at the cost I was quoted for a replacement. The BMW service centre 'cleaned up' the calliper and refitted it. A few days and 9 miles later my rear wheel locked after about 100m of travel from home. The rear brake was locked solid. I removed the calliper and limped home. Thinking it was a matter of 'I told you so' regarding the calliper, I chose not to return it to BMW but instead I sent it off for refurbishment to Powerhouse Automotive in Chesterfield.They said that there didn't seem to be anything wrong with it but I had it refurbished anyway.
I got it back and refitted it and bled the brake line.
Seemed fine when I drove it 8 miles for its MOT - sailed through and brought it home. Lockdown kicked in and it sat in the garage until a few days ago when I took it out - and the rear wheel locked again.Problem solved by backing off the bleed valve and releasing the pressure.
I now find that the wheel will spin freely until I put the ignition on. If I don't use the rear brake at all, but press the front brake lever, within moments the rear brake is solid once more.
I'm thinking this must be an ABS problem. Has anyone got an ideas and preferably a solution which won't cost me £££££ at BMW again?

Hi Tony, my bike has just developed the same problem, was it the ABS pump that cause the fault or is it still on going?

 

[GREEN STRING]

Hi Tony, my bike has just developed the same problem, was it the ABS pump that cause the fault or is it still on going?

Guys not sure if this is the cause of your problems but my 2014 GS had the same problem on the way to work. I thought it was the rear calliper but my (trusted) local independent bike mechanic diagnosed the fault as the rear master brake cylinder sticking. He replaced it and I’ve had no problem since.
Fault happened at 97,000KM
now at 111,000KM.
It was the only time in 9 years the bike let me down so I can live with that. Hope this helps.

 

[DJ123]

On a recent service, it was noticed my pedal was sticking and was causing the calliper to drag on the disc. I'd noticed previously the Bike was occasionally stiff to push around, or the rear wheel didn't spin as often - but this was a frequent occurrence. The mechanic disassembled the bake pedal & pivot point, cleaned it up & its now free as a bird.