New Servo-ectomy

This section is dedicated to the new Rockster version of the R1150R.

Moderator: Moderators

Post Reply
eburr
Basic User
Posts: 20
Joined: Tue Dec 06, 2016 6:59 am

New Servo-ectomy

Post by eburr »

Greetings,
Eric here. I am the new owner of a pretty nice 2004 Rockster Tiger Stripe (Black and Orange) with 28,000 miles. I got a nice deal by buying the bike as-is with (among a few other niggles) a failed ABS/Servo system. Symptoms: minimal (residual) braking on the rear brakes, brake warning light steady and ABS light flashing on the dash whenever the brake handle or lever were engaged. The bike had already been diagnosed as a faulty rear servo by the local BMW dealer when I picked it up, and they had already tried a few things to bring it back to life.

After a bit of research, I decided against trying resurrect the system by pulling and cleaning the servo line filters and engaging in a full system flush that has been outlined many times on various sites. My rationale; it seems that too many folks either didn't have success with the process (waste of time), or just delayed the inevitable when the servo system failed again in the future and probably during a less than optimal time (ex: two-up tour loaded going down a steep mountain grade-oh poo!). Knowing what "residual brakes" felt like on the back of this bike, I really never wanted to experience what it might feel like to have the front servo go out on me, as that could easily become a life or death situation. With so many success stories converting the system back to manual, and owning a decently equipped workshop, I decided that more simple on an older bike was better, so i went for it this weekend. Here is the ABS/Servo-delete procedure I followed:

1.) I followed the standard process for tank removal (used a cardboard box with holes in it to keep screws in order-good tip!)
2.) Put plastic sheeting and shop towels over the final drive to catch drips
3.) Removed battery for battery access
4.) Disconnected ABS lines and rear ABS line bracket
5.) Re-plumbled braided flexible brake line with new copper crush washers from the caliper directly to the rear master cylinder
6.) Used lots of absorbent towels, pulled clips and removed ABS lines from top of servo pump unit
7.) More plastic and towels over things, I removed the front ABS lines from the front distribution bracket
8.) Jiggled, wiggled and fished the ABS lines out. I needed to bend one and cut another, probably due to my impatience or worry about drips splashing about that could ruin painted surfaces
9.) Pulled the big ABS wiring plug from brain module by pulling back on the side of the clip and lifting it off
11.) Removed a few additional screws as I recall to pull the servo with brain module out of the bike (it leaks a lot, so I suggest you put it in some type of container afterwards...also be diligent to look for any leaks you may have missed).
12.) I then put the servo pump assembly into a vice and drilled out the four tamper proof screws that hold the brain box (controller) onto the pump. Easy peezy.
13.) Carefully removed the wiring plugs and ribbon connectors from the controller with needle nose pliers
14.) Sealed the bottom of the controller box with several strips of standard (non-conductive) duct tape
15.) Went over the controller bottom and sides again with metallic vent duct tape. Created a 100% solid, air and water tight enclosure
16.) Screwed the controller onto an electrical receptacle blank that was just tad bit larger than the controller body using self tapping screws
17.) Ground the self-tapping screw protrusions from the back of the blank (now the bottom of the controller box)
18.) Coated electrical connector with dialectic grease and reattached it to the controller by pushing the connector on as far as it goes, and then slipping the locking tab back in place. Before you fuss too much like I did to get it to seat, it actually sucks the connector down when you push the locking tab in-who knew?!!
19.) I had just enough extra metal on my over-sized receptacle blank (now the bottom of the controller box) to drill and screw it to the elevated bracket that previously held the ABS pump.
20.) I removed and ground the positioning tab off of bottom of the front ABS distribution bracket (that mounts on the steering head), and cut the unused union (the one with two different sizes in it) from the bracket with a cut off wheel. This gave me better angles to work with.
21.) I struggled a bit, but was able to eventually attach both upper and lower brake hoses (from the reservoir above and to the calipers below) to the distribution bracket using existing banjo bolts and then reattach it to the frame. One again, I used new copper sealing washers on all unions.
22.) Bled the rear brake circuit for approximately five minutes using standard one man, two hand procedure (right hand to pump the brake lever, left hand to open and shut the bleeder).
23.) Bled the front circuit by using first my mighty vac, and then by hand reaching around the front of the bike to operate the brake handle with my left and the the bleed nipples with a wrench in my right. I bled the front circuit, being the most important, for about 15 minutes. I still feel like it has a tad more play than on my R1100RT, maybe 1/4", but they work fine.
24.) Bench tested brakes in place. No leaks and they feel pretty good
25.) Reinstalled battery
26.) Turned ignition on-blue ABS relay in fuse box was clicking away so I pulled it
27.) Brake system warning light still on dash so I disassembled the cluster to access the bulbs (easy) and pulled both brake and ABS warning bulbs for good measure
28.) Remounted the tank and attachments
29.) I broke one of the damned quick connect male-end fuel line fittings so I bought two new stainless steel ones (at an outrageous price BTW, like $80 US inc. tax for two) along with new crimp connectors, removed the old male-end connectors and installed the new ones. That was a very fussy job as the old fittings didn't want to come out of the fuel line, even after warming things with a heat gun. Ugh.
30.) Final reassembly of bike bits
31.) Double checked everything for leaks
32.) Test rode and everything was A-OK! I have heard some people say that they replace the rear master cylinder with a non-ABS model for better power, but I would highly question the need for this. I was able to accidentally skid the rear tire with not all that much pressure and wearing boots, so it certainly sensitive enough!

In hindsight, I probably should have bought a new V-shaped union for the front brake lines (the one for the non-abs model) from the dealer, as the straight angles on the existing piece are a little difficult to work with, but is certainly workable as-is. If you still have plastic male-end fuel quick disconnects, plan on buying metal replacements as they break very very easily and it is probably just a matter of time anyhow until they fail.There is a slight amount of free play in the brake handle which I may be able to adjust out using the lever control wheel, but overall, the brakes felt great, very effective, not nearly as grabby in the front and certainly less annoying with no servo wh :D :D ine now. Oh, and having a rear brake is a good thing too, as long as you don't over-use it like half of the riders I have met!

Credit goes to all of those who have documented the process before me, but please don't plan on a wham-bam thank you mam' 2-hour process. I am a meticulous mechanic, ASE certified since 1976 and still invested about 12 hours into the total process including the study of everyone's prior work and write-ups (lots of that), disassembly, retrofit, reassembly and testing when done, not to mention a run to a dealer 45 minutes away to obtain new parts (quick connects) on the fly. On ghat, be prepared to break quick connects if the plastic ones are still in place, finding a knackered or missing blind nut or maybe several, tatty wiring sheaths that need to be addressed and any other number of challenges you may encounter along the way, and addressing each as you find it can be time consuming. Once again, it takes a little time, but it's in the 30'sF now, so what better way to spend the day than in my workshop playing MC mechanic?! :D

Peace out.
eburr
Basic User
Posts: 20
Joined: Tue Dec 06, 2016 6:59 am

Re: New Servo-ectomy

Post by eburr »

Update: I played with the Rockster again tonight. There must have been just a tiny amount of air left in the front brake system that resolved on its own, as it is now as as tight as can be and with no free play in the hand lever at all. I encourage you to not be afraid to do this operation. It's easy, but a little time consuming. And these servo brakes, especially when the front circuit fails, are damned dangerous. I am looking forward to riding a safer and more simplistic bike now.
User avatar
peels
Basic User
Posts: 1121
Joined: Wed Jun 26, 2013 11:12 am
Location: Southeast Iowa, USA.

Re: New Servo-ectomy

Post by peels »

I am also an Eric. and I also am servo-less. 8) Only had a little wiring trouble during my operation. brown with yellow stripe looks brown. :lol: think it was still only 2 or 3 hrs.... or to be exact...5 newcastle beers. :lol:

the only issue ive heard of with a rockster servo-ectomy was the speedo is different to sort out than the roadster.

seems youre ok there.... =D>


peace out to you too brother! 8)
2002 R1150R. Helmets save more lives than loud pipes.
eburr
Basic User
Posts: 20
Joined: Tue Dec 06, 2016 6:59 am

Re: New Servo-ectomy

Post by eburr »

Hey Eric. Thanks for the shout out. I agree. In that number I spent easily (6) hours beforehand researching the process for my specific model to avoid needing to cut anything unnecessarily-I retained the ABS/Servor controller, and getting a read on various opinions and perspectives from those who have done the job already. The next (6) hours were spent not only doing the actual conversion, but pulling and cleaning the calipers, prepping and repainting all fasteners, running out to buy various parts (copper washers, blind nuts, fluids, fuel tank quick disconnects, etc.) repairing frayed and deteriorating wiring jackets, replacing missing fasteners, etc.

So you are right....the actual conversion can be done in about 3 hours of straight labor if you have everything you need on hand and experience no breakage. But if you are doing on it on your own bike, experience quick connect breakage like most people do and are looking to clean and tidy things up like I did, it will take longer. Oh, and my dealer, the closest place I could find for the fuel quick connects, is an hour away and the drive there and back was also included in the time calculation. Ugh! I am an ASE cert. wrench since 75' and may not be too quick anymore, but am meticulous, especially on brakes and on my own bike.....LOL!

Cheers!

Straight labor for just doing the job, 3 hours seems reasonable.
User avatar
peels
Basic User
Posts: 1121
Joined: Wed Jun 26, 2013 11:12 am
Location: Southeast Iowa, USA.

Re: New Servo-ectomy

Post by peels »

eburr wrote:Hey Eric. Thanks for the shout out. I agree. In that number I spent easily (6) hours beforehand researching the process for my specific model to avoid needing to cut anything unnecessarily-I retained the ABS/Servor controller, and getting a read on various opinions and perspectives from those who have done the job already. The next (6) hours were spent not only doing the actual conversion, but pulling and cleaning the calipers, prepping and repainting all fasteners, running out to buy various parts (copper washers, blind nuts, fluids, fuel tank quick disconnects, etc.) repairing frayed and deteriorating wiring jackets, replacing missing fasteners, etc.

So you are right....the actual conversion can be done in about 3 hours of straight labor if you have everything you need on hand and experience no breakage. But if you are doing on it on your own bike, experience quick connect breakage like most people do and are looking to clean and tidy things up like I did, it will take longer. Oh, and my dealer, the closest place I could find for the fuel quick connects, is an hour away and the drive there and back was also included in the time calculation. Ugh! I am an ASE cert. wrench since 75' and may not be too quick anymore, but am meticulous, especially on brakes and on my own bike.....LOL!

Cheers!

Straight labor for just doing the job, 3 hours seems reasonable.
oops.. yes! my pre operation internet perusal easily equaled yours!

hahah I was BORN in 75. so it appears our similarities have ended, at names and motorcycles :lol: :lol: :lol: :lol: :lol:


fuel disconnects, I just threw in barbed connectors. no need for quick connects, and dont like em. just keep a screwdriver with me.
2002 R1150R. Helmets save more lives than loud pipes.
eburr
Basic User
Posts: 20
Joined: Tue Dec 06, 2016 6:59 am

Re: New Servo-ectomy

Post by eburr »

Well, I felt the quick connects did serve a purpose, so I decided to retain them. If you don't have them, removing the fuel tank will involve fuel spill unless you do something like use hemostats or fuel line clamping pliers. I felt it was worth it to retain and upgrade them. Now that evap. canister, well that was a different story. I'm kind of with Chris Harris on that. No good reason and good riddance to dead weight and another potential problem causing device.
WanderingRider
Basic User
Posts: 2
Joined: Sun Dec 11, 2016 12:02 am

Re: New Servo-ectomy

Post by WanderingRider »

I have also done the same ABS removal, and used virtually the same process as eburr, I finished mine last winter and rode it all summer. I did get the non-ABS banjo for the front brake lines. The conversion works fine, and I also like the simplistic reliability of basic hydraulics for my brakes.

I like your idea of using an electrical receptacle to mount the remaining electronics back in the ABS bay under the tank. I initially thought I could just leave this disconnected, but immediately discovered it runs the speedometer, and I've had it bundled up in there with tape.

Incidentally it appears that my system may have failed from a blown transistor on the controller board that I pulled off the side of the ABS servo unit and retained for the speedometer. The servos still worked when removed, if anyone out there wants that part they are welcome to it.

I've been pondering the feasibility of using the space under there for a reserve tank. I hate the idea of wasted space in there, so another casual thought has been to mount a battery where the ABS servo unit previously went and using the space for the original battery as.......... So far I'm long on ideas and short on action.
eburr
Basic User
Posts: 20
Joined: Tue Dec 06, 2016 6:59 am

Re: New Servo-ectomy

Post by eburr »

Re empty space where the servo pump was: there is a bit of excess space under the tank now for sure, but considering the need to pull the tank to effectively access it, I'm not sure what good it would do to move the battery forward to use the battery space for something else. I am kind of excited about shedding some of the bike's weight to make it less top heavy, so I'm not in a big hurry to fill that space up!

Splitter: I think I will order the non-abs front brake line union/coupler/splitter though, as that is one piece of the job I didn't feel I did as well as I could have. The angles without it seem a little forced.

Remaining Components: Did anyone who has done this job go on to remove the ABS tone ring from the front wheel (and add spacers to make up the width)? What about removing the ABS sensors from each brake caliper and plugging them? I haven't seen that addressed anywhere. It would be nice to make the bike look like it never had the ABS/Servo system on it in the first place!

Credit to Others: I have seen and used much better write-up's than mine, with pictures, which I studied before ever buying this bike. Full credit goes to those who did it before and shared their processes, although retaining the existing servo controller can't be stressed enough as the cleanest, no cutting way to do the job.

Why to Consider It: Once again, for those debating the process; if (O.K.-when) a servo or a circuit controlling one in the brain box goes, you get "residual braking" which feels, both to me and others who have experienced it, like about 30% of the normal non-servo assisted braking power-it's very hard to stop the bike with it. And if it happens at a bad time, on the front circuit and unpredictably (like when needing to brake quickly, or possibly two-up or tour loaded and coming down a mountain), it could well result in a fatal situation. I can't tell you how much more confidence removing that faulty system on my bike has given me. I'm not dumb though, and if I had been able to discover a simple and cost effective alternative to retain the ABS (but lose the servo assist) I would have probably gone that route instead, or then again, maybe not. My R1100RT's ABS system has been non-operative since the day I bought it and I could frankly care less. My non-servo, non-abs, non-linked brakes work great on that bike. The clunky transmission, though, is whole different story!
WanderingRider
Basic User
Posts: 2
Joined: Sun Dec 11, 2016 12:02 am

Re: New Servo-ectomy

Post by WanderingRider »

I to have looked at that ABS ring and thought it would be nice to get rid of it, but the front ring drives the speedo. I believe there is a mechanical speedo drive that came on other model bikes of the same year, but I haven't looked into the logistics of a swap out.

I would be curious if a newer nonservo ABS system could be integrated with these older bikes. It's a shame not to have ABS when you are on the road, but the servo system was an over engineered and poorly crafted solution.

Aside from that servo whine, one thing I really don't miss from the old ABS was the "grabby" feel that it had when maneuvering in parking lots, easing up to a stop, etc. It used to remind me of my old /5 which had the double leading shoe drum brakes, and they would tend to grab like that as well when I was trying to gently modulate the front at slow speeds.
User avatar
peels
Basic User
Posts: 1121
Joined: Wed Jun 26, 2013 11:12 am
Location: Southeast Iowa, USA.

Re: New Servo-ectomy

Post by peels »

eburr wrote:Well, I felt the quick connects did serve a purpose, so I decided to retain them. If you don't have them, removing the fuel tank will involve fuel spill unless you do something like use hemostats or fuel line clamping pliers. I felt it was worth it to retain and upgrade them. Now that evap. canister, well that was a different story. I'm kind of with Chris Harris on that. No good reason and good riddance to dead weight and another potential problem causing device.

yep.

evap canister went awol when I did the fuel line.

I'm not totally against the qd's, really the main driver of that was, I snapped the QD the day before a big ride. And I couldnt justify 85 bucks, when a $2 brass tube would do the same, with zero fallible parts. I called the nearest dealer,which is about an hour away, they didnt have any. but could order at a total cost of 120. yeah NOPE. Yes there's a gas drip. but I have cup I keep handy. And generally drain the tank prior to removal anyways.

sadly, I think the year might be done for me :( the temps are dropping way too fast. snow, icy roads... very different weather this year vs. last. :(
2002 R1150R. Helmets save more lives than loud pipes.
eburr
Basic User
Posts: 20
Joined: Tue Dec 06, 2016 6:59 am

Re: New Servo-ectomy

Post by eburr »

To Wandering Rider: I kind of figured that the tone ring on the front or rear controlled the Speedo via the ABS sensors. Glad I didn't pull them! No biggie. I can live with that and explain, if necessary to any future owner, my rationale for gutting the system. I also agree that the servo assist front brakes were grabby, but just imagine if the servo failed! Then you would have had a hand full of almost nothing. Ugh. The more I read about the servo brake system BMW designed for this year, the madder I get. Imagine the number of people who are no longer here to explain what happened in their braking mishap! As a former insurance claim investigator/trainer/manager I have no idea this issue wasn't successfully litigated many years ago. It's an easy case in my mind, but BMW does have some deep pockets.

To Eric (Peels), I get all of the above and agree with the rationale. I just felt like retaining and even upgrading the quick disconnects. After a fair amount of research, I found plastic replacements like the OEM (but in clear) for dirt cheap on-line, but decided to upgrade to the stainless steel male-ends instead, to save me or someone in the future from future breakage. As fair as weather and the end of our riding season, I am in N.E. Ohio in the Akron area and we are definitely done riding for awhile, which is why I have the time to obsess and upgrade this ride, as well as service all my buddy's bikes on my lift and in my shop! It's my Zen.
User avatar
peels
Basic User
Posts: 1121
Joined: Wed Jun 26, 2013 11:12 am
Location: Southeast Iowa, USA.

Re: New Servo-ectomy

Post by peels »

"imagine if the servo failed" that was the final straw. it "failed" on me one morning. (low voltage due to cold and lack of use I assume) just down the street from my house going only 25. Already dealing with the sticky rear brake caliper, and going through pads more than once a season, and TERRIBLE MPG, that was it. I thought "what if that happened at 65 coming into the 90deg corner on the way to work, or 500 miles from home in traffic....?" BuhBye abs.

I admit, all things 100% working, GREAT system, works as it should. but when anythings slightly outta sorts, the complexity made me feel unsafe due to multiple worst case scenarios. overly german! :lol:

and i'm with wanderingrider. that whine is not missed. brakes more responsive and smooth.
2002 R1150R. Helmets save more lives than loud pipes.
Post Reply