ABS Pressure Modulator failed (again) - 2005 R1200GS

Greybeard

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So, I first had a problem with the ABS pressure modulator on my 2005 R1200GS in 2008 when it was replaced free as a goodwill gesture. It failed again in 2016 when the bike was 11 years old - this time it was replaced under extended warranty (which made the warranty seem well worth it!!!).

And this last weekend during an afternoon ride to bed in my new Conti-Trail Attack 3 tyres I once again got a solid red triangle + rapidly flashing brake failure lights come on. The front brake servo was activating but pressing on the rear brake pedal = nothing (or residual braking only).

Took it into the dealership yesterday for analysis, and was told the modulator had failed again. Only now apparently BMW don't have this part (# 34 51 7729061) available anymore - it is officially obsolete!

I love the bike (which I've had from new), so I really don't want to give it up. My dealership said that it is possible to get a part from Motorworks which would bypass the pressure modulator which would give me braking but with servo assist or ABS - I'm wondering if this is the right path to take assuming that BMW UK can't find a new part anywhere else... has anyone else used this method or done something else I should be considering? TIA
 
You seem to have done very well compared to other people. Yes they are a lovely bike. Might even be the best version as each subsequent model put on weight. But it might be time for a servorectomy. JJH
 
Yes, the 2005 has servos. The normal ABS pump (like in that video) only runs to pump the brakes back up during ABS operation (and also runs during the self-test). The servo units run every time you brake and are horribly unreliable, and if you fix one thing, something else goes wrong very soon. The servo by-pass kit is only linking your brake pipes from your master cylinders to your calipers, nothing more. You can do that with direct pipes/hoses. The servo bypass kit also requires you to keep the ABS electronics, and doesn't stop the warnings. You have to tape over the lamp.
Given that the replacement is horrendously expensive in relation to the value of the bike, it's just not worth seriously considering, so your choices come down to bypassing the servo (a "servoectomy"), sell the bike as it is, break it for spares. I'm still pondering what to do with mine after repairing the unit three times, the electronics committed hari kari, that's when I discovered that the bike has no fuses to protect anything from burning itself out!
 
You have 3 options

1) Scrap the bike, call it a day and get something newer
2) Try and find a new old stock or Sh unit - the former ok, the latter fraught with its own problems
3) Perform a servoectomy

Basically split the servo from its electrics (you need to keep the electrics) and fit a few new brake hose routings i believe

You also need to block the red ABS fail leds on kombi as well

You left with a bike with std non abs brakes

does it work - yes will it stop you - yes - but not with any ABS function

plenty of bikes out there with servoectomys i had one with no issues

loads will jump in with legality, insurance , world peace etc


All i have provided is some options , the route you take is up to you ;)
 
Santa-2512 said:
You have 3 options

1) Scrap the bike, call it a day and get something newer
2) Try and find a new old stock or Sh unit - the former ok, the latter fraught with its own problems
3) Perform a servoectomy

Basically split the servo from its electrics (you need to keep the electrics) and fit a few new brake hose routings i believe

You also need to block the red ABS fail leds on kombi as well

You left with a bike with std non abs brakes

does it work - yes will it stop you - yes - but not with any ABS function

plenty of bikes out there with servoectomys i had one with no issues

loads will jump in with legality, insurance , world peace etc


All i have provided is some options , the route you take is up to you ;)
Click to expand...

Thanks for your advice, I think my preference will be:
a) find a new old stock unit
b) perform a servoectomy
c) scrap the bike

Apparently the local dealer says that the issue has been escalated to BMW in Berlin, so fingers crossed...
 
Greybeard said:
Thanks for your advice, I think my preference will be:
a) find a new old stock unit
b) perform a servoectomy
c) scrap the bike

Apparently the local dealer says that the issue has been escalated to BMW in Berlin, so fingers crossed...
Click to expand...
Re 1).

Dont hold your breath

Normally spares are life of vehicle plus 10 years.

The servo abs unit was only fitted till 07/08. I believe (waits for some one to come along to prove me wrong), so spares production would have ended 2018 / 19

You may be lucky that there was an eol build which would put a lifetime (one off) qty into a stock location somewhere.... However

You may want to be sitting down for the next bit

The cost for a unit ex vat is around £1300

So unlikely to be a stock location with a vast qty in somwhere 😕

Speak to Steptoe. (forum legend)

He probably has the most experience with this issue, and will have good advice on what to do next
 
In addition to the above,
The abs unit has to be coded to the bike,
A working sh unit can’t just be fitted,without dealer level diagnostics.
If the bike is all good apart from the abs,just remove it as a 2005 bike is worth very little anyway.
Welcome to the future of economically unrepairable bikes,it’s what you all cried out for and bought.👍
 
I suppose it depends on what type of rider you are and experience, I grew up without ABS I do lots of off roading and most of my bikes don’t have ABS fitted.
So I would remove it and carry on.
I have friends that are so dependent on rider aids I doubt they could survive a long ride in the rain without ABS.
 
A simple question to ask yourself. In your normal everyday driving did you feel the abs come in? I doubt it. I’d remove it and carry on. I actually had an early 1200 without the abs. I don’t have any problems. JJH
 
buy a loom and a later ABS 2 module and update to the later fail more often - but repairable unit - Sherlock will likely sort u for around 300 - ask nicely and get the brake pipes too

removal of the unit - is a legal minefield - your insurer should rightly refuse to pay out, and the police should in a nasty incident lock you up for death by dangerous driving

this is not new - they first did in to a ford Granada driver circa 2000 that wiped someone out at the old A40 traffic lights at uxbridge - they had him on camera locked up at 80 mph all the way in to the crash - yet all granada's of that model, had ABS - the Chassis number tells everyone what options where fitted
 
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I had a 2005 avec Servo, never had a problem (and considering that the fluid was changed only once, perhaps I was lucky)

If I had encountered the problems you have, I would not hesitate to hit the servo-ectomy button.

By many reports, the brakes feel better post op...

Hope you get it sorted but chucking the amount of money required to replace the unit on a bike of that age seems illogical
 
botus said:
- yet all granada's of that model, had ABS -
Click to expand...

But not all GS’s had abs/servo fitted.
It was an option. It was never an option on a Ford Granada.
Removing the abs/servo you’re converting it to non-ABS spec .
I’ve had a few insurance repairs involved in accidents that have had the servo/abs removed and insurance haven’t queried the removal.
 
Steptoe said:
But not all GS’s had abs/servo fitted.
It was an option. It was never an option on a Ford Granada.
Click to expand...

interesting perspective

the owner will still need to mention to the insurer about a modification to the vehicle and I'd expect the insurer to get uncomfortable about a mod to remove a braking safety system - at best an engineers certificate would be sensible for them...


could be in luck - its on cars looks like on bikes they haven't bothered with this yet......
and if the MOT man is on his game he should be checking with that VIN it passes the idiot self check (at key on) - which its compulsory to pass in today's world - and won't for an ABS if its been disabled

wow - just checking regs and found this

It’s not permissible to remove or disable the ABS from a vehicle first used on or after 1 January 2010. Not all vehicles first used on or after 1 January 2010 will have ABS, so the failure only applies where the system has obviously been removed.

www.gov.uk

MOT inspection manual: cars and passenger vehicles - 1. Brakes - Guidance - GOV.UK

Brake condition and operation, service brakes, secondary brakes, parking brakes, anti-lock braking system (ABS), electronic braking system (EBS) and brake fluid rules and inspection for car and passenger vehicle MOT tests.
www.gov.uk www.gov.uk
 
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mikeyboy said:
In addition to the above,
The abs unit has to be coded to the bike,
A working sh unit can’t just be fitted,without dealer level diagnostics.
If the bike is all good apart from the abs,just remove it as a 2005 bike is worth very little anyway.
Welcome to the future of economically unrepairable bikes,it’s what you all cried out for and bought.👍
Click to expand...
Err not the case.
I replaced mine myself with a used Motoworks item and no coding was required. Nimble fingers however were essential.
And Botus, check the O/P location...........
 
Bem said:
Err not the case.
I replaced mine myself with a used Motoworks item and no coding was required. Nimble fingers however were essential.
And Botus, check the O/P location...........
Click to expand...
if you buy secondhand parts - some can work - if the donor was the exact same spec bike (car) often it will be plug and play....
but imagine you buy an RT ABS modulator and fit on a GS, the ABS might work as they accept quite a large tolerance between wheel speeds under braking (or maybe it copes but cuts in later / earlier than its meant too....) but a bigger bit of fun might be ASR cutting power wrongly /arguing - on Cars lots fight ESP and Traction control, but ABS doesn't seem to care very much.

the big issue with other parts, is where the gits load the VIN in the modules (like engine ECUs) and you need tools / bravery to get at in secret dealer / dev tools, that most burger flippers at the dealership don't have a clue how to use

As for can you / should you / is it legal too, principles are worth thinking about, not the country

I'm left perplexed UK MOT has "no mention of ABS on Motorcycles" - construction and useless regs - are old rubbish from 1986 with multiple unclear amendments every year since, and then we get alleged legislation saying "vehicles after 2010 can't have ABS removed"

and it gets even better - the haulage industry rattled cages to get clarity on side of the road lock up lorry driver checks - the law now states "vehicles" can't carry on a journey with a Red ABS light illuminated, unless you can prove it was working correctly when you started out on the journey that day !!! - in my head that translates as you need to keep a video clip each time you crank the vehicle in to action....
 
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O/P lives in that other island, where we dare not say the name.
No "real" MOT = no worries.
 
Bem said:
O/P lives in that other island, where we dare not say the name.
No "real" MOT = no worries.
Click to expand...
You are right - in fact no MOT at all for larger bikes (yet) in this isle. However, I'm not minded to be cavalier about brakes - I want them to work (with or without ABS)... I don't think I'll try and get a s/h unit.
 
My first bike was servoectomised

Never had a problem, as i never got into a situation where i needed abs, i locked the back end once, noted it didnt need shit loads of pressure, and adapted accordingly.

When it went for an mot, it passed, nothing was noted about no abs, and they dont test for it
 
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