Does the ABS warning light go off normally?
Does the rear pedal activate the tail/brake light?
Several ABS threads here with basic search. Most don't end well.

 

The warning lights give no indication of a problem until I activate either the pedal or hand lever. When activating the foot pedal, the general fail light comes on solid and the ABS light starts flashing 4 hz within a second or two of pressing the pedal. Both go out when the pedal is released. When using the hand lever, after a few seconds the general light comes on solid and the ABS fail light flashes 4 Hz and they stay on even after the hand lever is released until switching off the engine. This seems to agree with the chart in the Clymer.
The rear pedal does activate the correct filament in the brake light. The brakes pass both the startup self test and the roll off test. Conversely, if I hold down the foot brake first and then turn on the key, it (correctly) fails the startup self test.

 

Just be ready to bypass the whole stupid thing and be done with it. I too hate losing the ABS, but it's such an over-the-top complex system there's just no way around it.

 

Mine was giving me problems after being serviced by the dealer before I acquired it (long story). The servo motor was running continuously and quickly drained the battery. I just decided it would be better to just dump it now rather than fixing and still have failures in the future. I split the cost with the previous owner/friend so I went with the RH unit. The RH unit is very well made and has the electronics with it. You can go the other route and remove your electronics from your servo unit. Removing that unit is not an easy task. Its really tucked in there and is mounted on a plastic tray which makes it a pain to remove because I didn't see any way to remove the three screws on the bottom of the tray holding the servo.

Here is the unit removed

Here is the RH unit mounted on the plastic tray

And the RH unit installed

My front brakes worked great, however the back not so good. The rear uses a 16mm master cylinder. By switching to a 13mm Brembo which can be bought new for around $52 increased the stopping power of the rear considerably.

 

Mine was giving me problems after being serviced by the dealer before I acquired it (long story). The servo motor was running continuously and quickly drained the battery. I just decided it would be better to just dump it now rather than fixing and still have failures in the future. I split the cost with the previous owner/friend so I went with the RH unit. The RH unit is very well made and has the electronics with it. You can go the other route and remove your electronics from your servo unit. Removing that unit is not an easy task. Its really tucked in there and is mounted on a plastic tray which makes it a pain to remove because I didn't see any way to remove the three screws on the bottom of the tray holding the servo.
View attachment 32575

Here is the unit removed
View attachment 32576

Here is the RH unit mounted on the plastic tray
View attachment 32577
And the RH unit installed
View attachment 32578
My front brakes worked great, however the back not so good. The rear uses a 16mm master cylinder. By switching to a 13mm Brembo which can be bought new for around $52 increased the stopping power of the rear considerably.
View attachment 32579

 

So is the RH unit just a blanking plate with some smarts to fool the ecu that abs is still present?

Re 16mm vs 13mm rear brake master cylinder, is this the same for the later K1300GT? The max bmw parts fiche does not list item #3. Would be a good upgrade imho.

Love your workshop btw

 

The RH unit is complete with the electronics which allows operation of the speedometer, at least on my model year and does fool the ECU I guess. The unit is very well machined with bypass ports. Not sure who makes the other option which is just a stamped out piece of steel and tubing and ports to connect your lines. It has a blanking plate you use to connect you original electronics after you remove them form your unit. Do a search on servo problems and it will probably come up. If you go with the RH make sure you get the correct model. There is one for analog or Can.

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Fachbetrieb RH Electronics » Reparatur von Second Life KIT zum Festpreis ✅ 24 Monate Garantie ✅ Sofortservice: 1 Werktag

shop.rhelectronics.de

 

Cheers, thanks for the link, it answers my question:
"THE CONVERSION KIT TO REPLACE THE FAULT-PRONE BMW ABS 3
The conversion kit for the fault-prone BMW ABS III and ABS II. Available in five variants, for BMW motorbikes built between 2000 and 2006. The device replaces the standard ABS 3 of the manufacturer FTE and is instead installed in the motorcycle. It hydraulically connects the control circuits with the brake circuits, thus the brake system operates as conventional without ABS system."

Mines a 2009 built K1300GT, so I understand this kit is not needed for my bike, not to say the 09 ABS is less prone to issues...but touch wood nothing yet...

The rear master cylinder size may be worth a look, rear brake performance is a bit lacklustre, but as it's linked, may not be smart to increase line pressure by going to a 13mm master may upset the balance. Hmm, food for thought....

 

Without checking for trouble codes the shade tree mechanic assessment would be that If the abs passes the roll off test it would seem to indicate that the servo motors, brake light circuit, brake switches and fluid level sensors pass the self test. Since a problem is indicated upon application of braking it would seem to indicate either a leak, or, a pressure transducer problem in the unit. But that's just a guess without knowing codes.

 

That's what i was thinking. Was just hoping there was something obvious I maybe missed. On another note, sort of: How do you like those Italian brake hoses?

 

What ever the problem may be with the unit you still have something that is overly complicated and prone to fail. Bottom line your going to spend a ton of cash to keep that unit in place. In my case I didn't get any codes that told me the explicit problem with the servo unit other than the brake failure itself. It may be wise to get a code reader and check for any codes. Your problem is different from mine as my servo motor ran as soon as you turned the key and the the general fail light came on with ABS flashing 4 HZ. I had front brakes but no rear at all. All fluids were full. I could have pulled the unit and fiddled with it but in the end its still prone to fail.

 

Going to dig into it this weekend and see what I can see. The RH unit does look interesting, thanks for the heads up on that. Does it still allow use of cruise control?

 

Yep, Servo ABS is the dumbest thing ever put on a motorcycle. So complex some of the best ABS overhaul outfits in the US and Europe have been unable to repair it. When you consider they can rebuild ABS units on expensive BMW cars and Ferraris, that's saying something.

 

No problems with the FrenTubo lines. Initially they sent the wrong front lines but the exchange was painless. I could've used the first pair but would've had bend the banjos a little more. The shipping from Europe was a lot quicker than I was expecting.

 

Servo ABS removal unit

For ABS removal on bikes fitted with Servo ABS

www.motorworks.co.uk

Here's a link to the Motor Work's "Servo ABS Removal Unit"

 

The servo unit on that bike they show for the Motor Works unit looks like its in a much easier to remove location than on the K1200S.

 

I have one of those doo-hicky’s I bought for my K1200RS - except the KRS has no machinery like that. Apparently, K bikes are called out as one group, but not all the K bikes are the same.

Removing the ABS is WAY easier on the pre-‘98 bikes. My safari thru BMW forest will be finished soon (requiring a visit to a Beemer Shop), and I will tell you about the complete difference than a K from ‘96 to ~2000. The older models only need the pass-thru tubes (about $75), and believe it or not, you can ride the bike easily by simply removing the electronic side of the goofy brake system. I will explain my route thru the jungle as soon as I can figure it out - maybe next week when my bike comes back from the shop after the ignition module is brought back to life.

I surely don’t agree with ALL K-bike riders - but dang those machines are hair-raising….

 

Peter in here question for; Craz1. Thank you your post is very helpful! I want to ask about where to get the RH unit in your post? My 05 K1200S it’s servo assist abs unit has been back and forth to Module Masters in Idaho never fixed completelY. First time I did all the diagnostics and wrenching I have a GS911, I-have done all the wrenching up to recently. Then after continued problems am having Ben Goff Owner/Mechanic of Kona Beemer Shop,LLC. Working on trying to fix the abs problems, he has validated my work. I can not say enough about BenGoff and his knowledge an avid BMW rider /mechanic , also the only BMW motorcycle shop on Hawaii, Bigisland ! Thanks agin

 

Peterin here to craz1; where can I buy the RH unit to surpass the servo assist abs unit on my 05 K1200S, giving up on twice trying Module Masters to rebuild it they are having difficulties . I like the beefy looks of the RH unit. Thank you

 

RH Electronics, Germany. They ship overseas.

I'd be inclined to try Motorworks, first. Less expensive and does the same thing. The RH unit does have programmable modes so you can bypass certain features like the ABS self-check / warning lights but you can accomplish the same thing by pulling the ABS relay and removing the warning lamp.

As a matter of fact, I'm thinking about ordering 1 just o have on hand if the ABS unit on my K12RS gives up the ghost.

 

Any body here try the Polish outfit on ebay uk that has you send in the abs electrics box to mate to their bypass plate?

 

Hi, ‘03 K1200RS here with identical symptoms. What did you end up doing to fix yours?

cheers,

Atle