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Discussion Starter · #1 ·
Hi I'm new to the forum, but I have a very disturbing problem with my braking system.

About 8 months ago I changed the rear pads, no problems, about 150 miles later the rear brake pipe literally popped out of the banjo and sprayed fluid all over the back tyre, very scary.
I replaced the pipe and bled the system and again all seemed fine. The next day whilst on the motorway at 70mph there was a large pop sound and the bike shot forward.
I pulled over to investigate as I now had no rear brake.
The disc was nearly white hot and the calliper and pads had melted. (see pictures)
I have now sourced a new calliper and pads.
I was expecting the disc to be kaput, but after testing the disc is not warped and has no fractures (nice ring)
I fitted the new calliper and bled the rear braking system with fresh fluid (bled 500ml through it)
The rear brake now works perfectly independently, but when the front brake is applied, the ABS pump makes a weird mechanical sound and it locks the rear wheel. (I suspect the boiling fluid damaged the pump)
I also think that the initial problem I encountered was due to a faulty linked braking system.

My question is has anyone bypassed the linked braking system to make the back brake stand alone?

The bike works fine with the rear brake decommissioned. (I never use it anyway), emergency stops are not a problem and I use the tremendous engine braking as my rear brake, but it would be useful to have one for when my MOT is due.

also is there a rebuild kit available for the ABS pump?

I don't have a GS911 unit so I don't know if the ABS pump is getting bled correctly.

Thanks in advance guys.
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2018 K1600GT Opt 719 Blue Planet Metallic
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Welcome to the forum. I can't address bypassing or rebuilding the linked brake control valve. I'm guessing the pistons weren't retracting and everything heated and burned up or boiled fluid maybe at white hot temps. You need something to correctly bleed air, GS911 or maybe the motoscan I've seen referenced by others. Or possilby, a certified shop. Glad things weren't worse on you. Keep us posted on how it goes. I'm sure more qualified mechanics will have thoughts and chime in shortly.
 
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Mr.Fix It
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I'd take it to a dealer for troubleshooting. To unlink the frt/rear brake would require modifying the ABS pump; e.g. not practical or, from a safety stand point, desirable.

FWIW, WRT to your initial problem, if I had to guess I'd say there's quite a few miles on your bike and the rear caliper wasn't properly maintained. The rear caliper is free floating on 2 pins. Those pins can corrode, freeze up, causing the caliper to seize. The rear caliper should be checked periodically.

Duane
 

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I think your abs module is bad. Probably a stuck valve from the beginning. You really shouldn't be doing this stuff without all the correct tools in the first place. As G said, you should take it to a dealer at this point. Sorry to say, Plan on a hefty bill.
 

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Discussion Starter · #5 ·
I'd take it to a dealer for troubleshooting. To unlink the frt/rear brake would require modifying the ABS pump; e.g. not practical or, from a safety stand point, desirable.

FWIW, WRT to your initial problem, if I had to guess I'd say there's quite a few miles on your bike and the rear caliper wasn't properly maintained. The rear caliper is free floating on 2 pins. Those pins can corrode, freeze up, causing the caliper to seize. The rear caliper should be checked periodically.

Duane
Calliper was good mate and only 30k on the bike.
There's no safety issue in de-linking the brakes as the ABS is still working on the front brakes and I will then have a working back brake.
Definitely a fault in the ABS as the noise it makes when there is fluid in the rear system is not normal.
I'm just interested if anyone has done it, before I have to figure it out. I am a motorcycle mechanic, but mainly Jap and Harley.
I'm interested to see if it's doable without too much cost/fuss.
Cheers for the reply though.
 

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Hi I'm new to the forum, but I have a very disturbing problem with my braking system.

About 8 months ago I changed the rear pads, no problems, about 150 miles later the rear brake pipe literally popped out of the banjo and sprayed fluid all over the back tyre, very scary.
I replaced the pipe and bled the system and again all seemed fine. The next day whilst on the motorway at 70mph there was a large pop sound and the bike shot forward.
I pulled over to investigate as I now had no rear brake.
The disc was nearly white hot and the calliper and pads had melted. (see pictures)
I have now sourced a new calliper and pads.
I was expecting the disc to be kaput, but after testing the disc is not warped and has no fractures (nice ring)
I fitted the new calliper and bled the rear braking system with fresh fluid (bled 500ml through it)
The rear brake now works perfectly independently, but when the front brake is applied, the ABS pump makes a weird mechanical sound and it locks the rear wheel. (I suspect the boiling fluid damaged the pump)
I also think that the initial problem I encountered was due to a faulty linked braking system.

My question is has anyone bypassed the linked braking system to make the back brake stand alone?

The bike works fine with the rear brake decommissioned. (I never use it anyway), emergency stops are not a problem and I use the tremendous engine braking as my rear brake, but it would be useful to have one for when my MOT is due.

also is there a rebuild kit available for the ABS pump?

I don't have a GS911 unit so I don't know if the ABS pump is getting bled correctly.

Thanks in advance guys. View attachment 168292 View attachment 168293
You mention you have decommissioned the rear brake. If panic stop at speed is needed, sounds like you will hit whatever caused need to stop or maybe a trip over bars with ABS failure.
Definitely trip to dealer needed or fix by someone who totally understands system and has GS911. I've never bled my K16 brakes but have on my R1150RS ABS. It's a process.
 

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About 8 months ago I changed the rear pads, no problems, about 150 miles later the rear brake pipe literally popped out of the banjo and sprayed fluid all over the back tyre, very scary.
I replaced the pipe and bled the system and again all seemed fine. The next day whilst on the motorway at 70mph there was a large pop sound and the bike shot forward.

I don't have a GS911 unit so I don't know if the ABS pump is getting bled correctly.
Without a GS-911 or Motoscan you cannot bleed the system properly - there's a remote chance that it might work once its bled correctly, but worst case the abs pump is destroyed from running dry.
 

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Discussion Starter · #8 ·
You mention you have decommissioned the rear brake. If panic stop at speed is needed, sounds like you will hit whatever caused need to stop or maybe a trip over bars with ABS failure.
Definitely trip to dealer needed or fix by someone who totally understands system and has GS911. I've never bled my K16 brakes but have on my R1150RS ABS. It's a process.
Had to do an emergency stop on a bend at 70mph when a mate on an aprilla 1000 wiped out in front of me, she stopped fine and much quicker than 2 other mates on a Honda cb1000 and a Honda transalp. No problem, didn't even do a stopie.
The stopping power of the front, coupled with the suspension is amazing.
I agree I need a gs911, but I'd need to get a pro one for my business as a 10 vin version would be uneconomical. As for taking it to BMW, I ain't paying their exorbitant labour costs. I might as well buy the GS911 as soon as funds allow.
Without a GS-911 or Motoscan you cannot bleed the system properly - there's a remote chance that it might work once its bled correctly, but worst case the abs pump is destroyed from running dry
I agree, although I think the ABS is more likely destroyed from boiling fluid.
However the ABS is working perfectly on the front, so is it a linked split system?
 

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I agree, although I think the ABS is more likely destroyed from boiling fluid.
However the ABS is working perfectly on the front, so is it a linked split system?
When I replaced my brake fluid I recall Motoscan has separate screens for cycling the ABS when doing the front and rear, so I expect its as you suggest, a linked split system.
 

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When I replaced my brake fluid I recall Motoscan has separate screens for cycling the ABS when doing the front and rear, so I expect its as you suggest, a linked split system.
Even linked they have to be separate for the abs to work right. But I doubt the abs controller is going to work at all if you disconnect the rear.

Not a good idea anyways.
 

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Mr.Fix It
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Had to do an emergency stop on a bend at 70mph when a mate on an aprilla 1000 wiped out in front of me, she stopped fine and much quicker than 2 other mates on a Honda cb1000 and a Honda transalp. No problem, didn't even do a stopie.
The stopping power of the front, coupled with the suspension is amazing.
I agree I need a gs911, but I'd need to get a pro one for my business as a 10 vin version would be uneconomical. As for taking it to BMW, I ain't paying their exorbitant labour costs. I might as well buy the GS911 as soon as funds allow.
Best you can hope for [if] you have a GS911 is that cycling the ABS pump will free something up.

Duane
 
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