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Coupla thoughts here.

There's nothing supernatural about rear brake "self destruction phenomena". The mayhem cited above is all too common, and only partially related to linked brakes. Linked brakes are certainly not the cause. Given enough miles under normal use without proper maintenance, all hydraulic rear brakes suffer from the same kinds of symptoms to some degree at one time or another. Though I've never had it happen to me in many hundreds of K miles, I've seen the aftermath many times on the road.

If you understand the operating principles and maintain your brakes properly, you won't ever have a prob. I've re-adjusted my rear brake multiple times on every one of 14 moto's, including the 3 currently in my stable, the last of which is a '15 GSA.

There's no reason to be afraid of adjusting your rear brake if you know what you're doing. The NEVER RE-ADJUST THE REAR BRAKE "rule" is wise to observe if you don't know any better. It's easier, safer, and more practical to have riders follow this rule than to get them to understand the underlying principles at work and risk them fiddling with it without knowing what they're doing. No doubt about it, the risk can be HIGH... A locked rear brake can be fatal, though it usually comes on gradually.

My GSW Haynes manual spec's a 1 mm gap between the top of the brake lever and frame strut, and cites no NEVER ADJUST "rule" whatsoever. Nor does the OEM rider manual. This gap should never be set tighter, though setting it a bit looser won't hurt a thing. I didn't hesitate to break the white factory paint on the adjustment nut when I wanted to open up the gap on mine.

The primary cause of rear brake symptoms of dragging, disk overheating and warping, self-destructing pads, sudden unintentional lock-up, and related brake trauma is neglect of service. I saw a rear brake disk on a Moto Guzzi V11 Le Mans at night by the side of the road that was glowing red due to unintentional dragging. When it cooled, bright rainbow colors indicated it had been de-tempered. Yep, this rider swore he hadn't touched his rear brake in years. He could not (would not?) understand what he had done (er, not done). I swear he thought it was haunted...

Since brake fluid is powerfully hygroscopic, it pulls water vapor out of the air. It's so powerful that over time, the small amount of water actually drawn through polymer brake reservoirs out of the air becomes significant. The root cause of allowing old, caustic brake fluid to pick up water in solution over time is that the fluid is no longer impervious to operating temps generated at the calipers. The water accumulated in solution quickly turns to steam at the caliper at the boiling point, expanding and creating steam bubbles that drag brake pucks against disks. That's where the trauma starts... 2 other cases where this happened to riders I came across on the road come to mind. The complaint both riders had was rear brake levers resting useless at fully depressed position. Both of these these riders said they never used their rear brakes.

The solution: Follow OEM brake maintenance intervals and regularly bleed and flush with new fluid as indicated. Shorten brake maint. intervals in humid, rainy, and 4 season climates. You can get away with lengthening maint. intervals in Phoenix and Death Valley.

It's a very rare rider I've run across who actually maintains his brakes properly.

...And so it goes...
 

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Coupla thoughts here.

There's nothing supernatural about rear brake "self destruction phenomena". The mayhem cited above is all too common, and only partially related to linked brakes. Linked brakes are certainly not the cause. Given enough miles under normal use without proper maintenance, all hydraulic rear brakes suffer from the same kinds of symptoms to some degree at one time or another. Though I've never had it happen to me in many hundreds of K miles, I've seen the aftermath many times on the road.

If you understand the operating principles and maintain your brakes properly, you won't ever have a prob. I've re-adjusted my rear brake multiple times on every one of 14 moto's, including the 3 currently in my stable, the last of which is a '15 GSA.

There's no reason to be afraid of adjusting your rear brake if you know what you're doing. The NEVER RE-ADJUST THE REAR BRAKE "rule" is wise to observe if you don't know any better. It's easier, safer, and more practical to have riders follow this rule than to get them to understand the underlying principles at work and risk them fiddling with it without knowing what they're doing. No doubt about it, the risk can be HIGH... A locked rear brake can be fatal, though it usually comes on gradually.

My GSW Haynes manual spec's a 1 mm gap between the top of the brake lever and frame strut, and cites no NEVER ADJUST "rule" whatsoever. Nor does the OEM rider manual. This gap should never be set tighter, though setting it a bit looser won't hurt a thing. I didn't hesitate to break the white factory paint on the adjustment nut when I wanted to open up the gap on mine.

The primary cause of rear brake symptoms of dragging, disk overheating and warping, self-destructing pads, sudden unintentional lock-up, and related brake trauma is neglect of service. I saw a rear brake disk on a Moto Guzzi V11 Le Mans at night by the side of the road that was glowing red due to unintentional dragging. When it cooled, bright rainbow colors indicated it had been de-tempered. Yep, this rider swore he hadn't touched his rear brake in years. He could not (would not?) understand what he had done (er, not done). I swear he thought it was haunted...

Since brake fluid is powerfully hygroscopic, it pulls water vapor out of the air. It's so powerful that over time, the small amount of water actually drawn through polymer brake reservoirs out of the air becomes significant. The root cause of allowing old, caustic brake fluid to pick up water in solution over time is that the fluid is no longer impervious to operating temps generated at the calipers. The water accumulated in solution quickly turns to steam at the caliper at the boiling point, expanding and creating steam bubbles that drag brake pucks against disks. That's where the trauma starts... 2 other cases where this happened to riders I came across on the road come to mind. The complaint both riders had was rear brake levers resting useless at fully depressed position. Both of these these riders said they never used their rear brakes.

The solution: Follow OEM brake maintenance intervals and regularly bleed and flush with new fluid as indicated. Shorten brake maint. intervals in humid, rainy, and 4 season climates. You can get away with lengthening maint. intervals in Phoenix and Death Valley.

It's a very rare rider I've run across who actually maintains his brakes properly.

...And so it goes...

Say what now......

Lol man very well written, I will say this the Caution Hot Liquid on the lid of the coffee cups at McDonalds only say that because they were sued a few times.

Common sense is not a common virtue!

>:)
 

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Coupla thoughts here.

There's nothing supernatural about rear brake "self destruction phenomena". The mayhem cited above is all too common, and only partially related to linked brakes. Linked brakes are certainly not the cause. Given enough miles under normal use without proper maintenance, all hydraulic rear brakes suffer from the same kinds of symptoms to some degree at one time or another. Though I've never had it happen to me in many hundreds of K miles, I've seen the aftermath many times on the road.

If you understand the operating principles and maintain your brakes properly, you won't ever have a prob. I've re-adjusted my rear brake multiple times on every one of 14 moto's, including the 3 currently in my stable, the last of which is a '15 GSA.

There's no reason to be afraid of adjusting your rear brake if you know what you're doing. The NEVER RE-ADJUST THE REAR BRAKE "rule" is wise to observe if you don't know any better. It's easier, safer, and more practical to have riders follow this rule than to get them to understand the underlying principles at work and risk them fiddling with it without knowing what they're doing. No doubt about it, the risk can be HIGH... A locked rear brake can be fatal, though it usually comes on gradually.

My GSW Haynes manual spec's a 1 mm gap between the top of the brake lever and frame strut, and cites no NEVER ADJUST "rule" whatsoever. Nor does the OEM rider manual. This gap should never be set tighter, though setting it a bit looser won't hurt a thing. I didn't hesitate to break the white factory paint on the adjustment nut when I wanted to open up the gap on mine.

The primary cause of rear brake symptoms of dragging, disk overheating and warping, self-destructing pads, sudden unintentional lock-up, and related brake trauma is neglect of service. I saw a rear brake disk on a Moto Guzzi V11 Le Mans at night by the side of the road that was glowing red due to unintentional dragging. When it cooled, bright rainbow colors indicated it had been de-tempered. Yep, this rider swore he hadn't touched his rear brake in years. He could not (would not?) understand what he had done (er, not done). I swear he thought it was haunted...

Since brake fluid is powerfully hygroscopic, it pulls water vapor out of the air. It's so powerful that over time, the small amount of water actually drawn through polymer brake reservoirs out of the air becomes significant. The root cause of allowing old, caustic brake fluid to pick up water in solution over time is that the fluid is no longer impervious to operating temps generated at the calipers. The water accumulated in solution quickly turns to steam at the caliper at the boiling point, expanding and creating steam bubbles that drag brake pucks against disks. That's where the trauma starts... 2 other cases where this happened to riders I came across on the road come to mind. The complaint both riders had was rear brake levers resting useless at fully depressed position. Both of these these riders said they never used their rear brakes.

The solution: Follow OEM brake maintenance intervals and regularly bleed and flush with new fluid as indicated. Shorten brake maint. intervals in humid, rainy, and 4 season climates. You can get away with lengthening maint. intervals in Phoenix and Death Valley.

It's a very rare rider I've run across who actually maintains his brakes properly.

...And so it goes...
When the title of the thread is "Raising the brake pedal" and the only way to do that is to reduce the already tight 1mm blow by I feel pretty confident in recommending that the owner not touch that adjustment.
 

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Discussion Starter #27
Update

I got a feeler gauge today (finding a 1mm locally was impossible) that was 1.02mm and reset the brake to that thinkness. I don't think .02mm is worth worrying about.

At the same time, I installed an Alt Rider brake pedal riser that I ordered a few days ago. It is fantastic (well at least sitting on the bike in the garage).

Interestingly enough the instructions included with the pedal riser talk about fiddling with the adjustment exactly how everyone is saying not to do it. I am so confused that I am just going to leave it as is but it's interesting that Alt Rider is saying to do it if you want although they do mention you can damage your brakes.

2015 R 1200 GS :: 2011 DRZ400S
 

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The key with adjusting the blow-by on the rear brake pedal is to not go any less than 1mm, there has to be some slack in there or the rear brake could remain applied even though your foot isn't pressing on the pedal, for obvious reasons this is bad, on the other hand going looser is not going to harm anything but since 99.9% of the time riders want that pedal higher is the reasoning that BMW and others caution against adjusting it, that and some people just can't get it right.
 

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Discussion Starter #29
You'd think BMW would have a better adjustment method at this point especially since that is a very critical ergonomic part of riding.

The Alt Rider riser is pretty bad ass though. Just wish it wasn't $100!

2015 R 1200 GS :: 2011 DRZ400S
 

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Agreed, you would naturally think that on a premium motorcycle BMW would have provided an adjustable brake pedal and shift lever, but then again they wouldn't able to hook their customers $360 for their over-priced accessory pedals.
 

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Great reply Hatch.
I have just had the same problem with my 2017 GS Rallye - which was serviced just before Christmas, but has just been overwintered in a slightly damp garage.
I went out first ride a few weeks ago & noticed that the rear brake started binding.
At first I thought that is was the engine losing power - I would stop for a few minutes & then it would go away.
Then it happened again -I was sure that I wasn't dragging the brake - so adjusted the brake pedal down a bit anyway - but it still kept binding.
Finally it just locked up completely - in the middle of a junction. I couldn't shift the bike in the middle of the traffic - so I had to just sit there like a lemon and wait about 15 mins for it to cool down and free itself off.
The only way that I could get back home was to unscrew the bleed nipple to let the pressure off & ride home with no back brake.
Took the calliper & pads off - (they were cooked) I couldn't see any reason why it was happening as everything seemed fine when it was cool.
I couldn't take it to the dealer as they are closed because of the current situation.with covid 19
Now have a calliper service kit & rear disk on order & will have to sort it out myself.

Lesson well learned. Always bleed your brakes after overwintering your bike.

I was very lucky it wasn't the front brake that went first.
 

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I had the same problem with the rear brake locking. Occurred while I was on the freeway in the middle of a very busy intersection at about 60 mph. By the time I got to the side of the road the rotor was glowing. After replacing the rotor, caliper and pads I took it out for a test ride and after riding for 5 miles without using the rear brake checked the temperature on the rotor. Approx 175 degrees. Waited for 15 minutes and rode it home. The problem in my case turned out to be caused by the metal brake shim that was fitted between the pad and the caliper. I reused the shim when replacing the pads. The heat from the brake lockup had deformed the shim and it acted like a spring pressing the pad in to the disk. Hence the extreme heat even when not using the brake. Thought I would mention it as something to be aware of if you are rebuilding the brakes. I removed the shim. Brakes are working without any problems.
 

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Cut a piece out of a plastic Carving board. Fix it to the top of the pedal and your done. If thats not high enough then repeat the process until your happy. No laser cut BS required.

There is a smaller bit bonded to underside of the white bit so that it wont migrate. Held in place with a piece of stainless wire. Been on there for years.

LOW TECH PROBLEM DESERVES LOW TECH SOLUTION.

26765
 

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Cut a piece out of a plastic Carving board. Fix it to the top of the pedal and your done. If thats not high enough then repeat the process until your happy. No laser cut BS required.

There is a smaller bit bonded to underside of the white bit so that it wont migrate. Held in place with a piece of stainless wire. Been on there for years.

LOW TECH PROBLEM DESERVES LOW TECH SOLUTION.

View attachment 26765
Same piece available from Touratech for 239.99. 😄 I love cheap and easy fixes for BMWs.
 
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