2004 r 1150 rt abs Problem

[littlewimp]

Hi All,

I'm new to the Forum and am after some advice regards the ABS on my recently acquired 1150 rt. I purchased it several months ago with a stripped gearbox input shaft so I removed everything to give it a freshen up including the abs unit, and now its back together and have bleed the braking system by following a you tube link, its still not working correctly1 the back brake bleed up with no issues but I'm having trouble in getting the fluid through to the front calipers, the bike was parked up for several years before I got it but the previous owner assured me that everything was working fine before it lost its drive. Any help/advice would be much appreciated. Thanks Neil.

[dirtrider]

Morning Neal

 

Are you keeping the ABS controller integral resiviours filled? (filler caps on the ABS unit itself)

 

Can you hear the servo motor operating when you pull the front brake lever with the key on?

 

We can probably help you BUT we will need a lot more info on what your brake system is or isn't doing during the bleeding process. (we can't see or hear it through the internet so you will need to be our eyes & ears)

 

 

[littlewimp]

Hi Dirtrider, Thanks for your reply, I started by bleeding the system from the front and rear master cylinders to the relevant 3 bleed nipples on the controller until I had clean fluid with no air, then I turned on the ignition and bleed the rear first making sure that the reservoir stayed topped up via a filling tube that I machined up with an m 18 thread on the end and a sealing washer, the rear bleed up easily but when I came to do the front calipers the flow of fluid was very poor and didn't really increase with the more travel I was applying to the front brake lever but the pump was running as soon as I touched the lever, now when the ignition is turned on the system check happens and the bottom light showing a triangle goes out leaving the top light flashing every second, if I put light pressure on the front brake lever the pump starts and then stops if I hold the lever in the same position then if I put more pressure on the front brake the pump pulses and the bottom light starts to flash, I realise that I need to ride the bike to get all lights off but on my maiden test ride earlier in the week although I had no warning lights present I had none or very little brakes. I have since checked everything and re bleed and although I haven't ridden the bike again things still don't seem as they should, when I had the pump removed from the bike I had it in a bag and probably upside down so I'm not sure if this could have affected anything also I'm not sure if I read something about some filters that are present in the pump and could require cleaning. I hope this helps.

[Sam Taylor]

Could it be the brake lines? Mine started sloughing off the interiors and totally messed up everything. Maybe time for new Stainless lines?

[littlewimp]

Thanks Sam, I did think about the Hoses so I released a fitting on the metal brake line before the flexible hose and the flow still seemed poor, there's still a good chance that the hoses are not good and I have made enquires about purchasing some stainless braided ones.

[Lowndes]

Thanks Sam, I did think about the Hoses so I released a fitting on the metal brake line before the flexible hose and the flow still seemed poor, there's still a good chance that the hoses are not good and I have made enquires about purchasing some stainless braided ones.

 

littlewimp, DOT4 brake fluid "attacks" paint, plastic, and sometimes the OEM brake lines. Seems to start at about the 10-12th year. Sometimes the brake lines then fail by "ballooning" and busting, but sometimes the insides of the lines start disintegrating and those shreds of brake line settle down into the calipers, blocking the small passages within the calipers, especially the front brakes. On my bike they acted as a check valve causing my front brakes to lock up.

 

Spiegler makes very good brake line replacement kits for most bikes and sells them thru a variety of dealers and Amazon ($20 cheaper there, too). Galfer also makes very good kits.

 

If you have any crud in your calipers, you will need to clear and clean them while replacing the brake lines. Fortunately, it isn't that difficult to do. Just "bleeding" or flushing the hydraulic hoses will not guarantee removing this stuff from the calipers.

 

Also, if you have a hydraulic clutch, you'll need to replace it too.

 

My front caliper, brake line inlet on the bottom, bleed nipple port on the top:

 

 

[littlewimp]

Thanks Lowndes, my bike is a 2004 model so that makes it 12 yrs Old ! I think I will take a look at the calipers later on tonight if I get chance. I will let you know what I find .

Thanks Neil.

[dirtrider]

Hi Dirtrider, Thanks for your reply, I started by bleeding the system from the front and rear master cylinders to the relevant 3 bleed nipples on the controller until I had clean fluid with no air, then I turned on the ignition and bleed the rear first making sure that the reservoir stayed topped up via a filling tube that I machined up with an m 18 thread on the end and a sealing washer, the rear bleed up easily but when I came to do the front calipers the flow of fluid was very poor and didn't really increase with the more travel I was applying to the front brake lever but the pump was running as soon as I touched the lever, now when the ignition is turned on the system check happens and the bottom light showing a triangle goes out leaving the top light flashing every second, if I put light pressure on the front brake lever the pump starts and then stops if I hold the lever in the same position then if I put more pressure on the front brake the pump pulses and the bottom light starts to flash, I realise that I need to ride the bike to get all lights off but on my maiden test ride earlier in the week although I had no warning lights present I had none or very little brakes. I have since checked everything and re bleed and although I haven't ridden the bike again things still don't seem as they should, when I had the pump removed from the bike I had it in a bag and probably upside down so I'm not sure if this could have affected anything also I'm not sure if I read something about some filters that are present in the pump and could require cleaning. I hope this helps.

 

Afternoon littlewimp

 

Can you hear the ABS pump change intensity & sound as you squeeze the front lever harder?

 

This is a good indicator (IF) the pump is actually pressurizing therefore you might have

blockage in the calipers or hoses.

 

If the pump noise doesn't change as you squeeze the front lever then you more than likely

have an internal controller pumping issue. (you didn't plug a line when you removed the

controller then forget to remove it did you?)

 

You did move your filling funnel to the OTHER (re front) ABS controller reservoir

didn't you?

 

It looks like other posters want to work with you on troubleshooting this so I will step aside

on this thread- (PM me if you need any specific info)

[littlewimp]

Thanks Dirtrider, I must admit that the pump doesn't sound as its pressurising to the same degree with the front brake as it does on the Back, I can only apply light pressure to the front and by keeping it constant the pump stops witch I'm guessing is correct, if I go past this point the pump starts to pulse !. obviously the brakes were working fine when the last owner was riding it before the drive failed but its been stood up for 3yrs since. I was hoping to get it finished and ready for springtime this will free up some room in my workshop ready for the delivery of a 1954 chevy pick-up which is being shipped from your side of the water later this Month.Its coming from here

2031 Nebraska Rd, Iola, KS 66749

Edited December 11, 2016 by littlewimp

[littlewimp]

Ive been out in the workshop to check the hoses and although I shall be changing them I didn't find any trace of debris in the calipers, then i thought I would just try bleeding the front brakes without the ignition on, and found that the fluid flow was no worse than trying it with the pump running, so I'm getting no assistance from the pump at all, I'm guessing that the abs unit is faulty but I'm still getting assistance when operating the rear brake ! its a shame that I cant get a detailed stripdown of the abs unit because I would be interested in stripping it down to understand how it works, I'm sure that there are people out there that can fix these units but I've had no luck in finding someone. I'm guessing that a new unit will be on my Christmas list.

[Boomer343]

If it was mine I would try a reverse bleed from the caliper to the ABS unit. Under normal circumstances given the possibility of debris making its way the the ABS unit it isn't a procedure to be used. I have had to do it on car abs systems a couple of times and it did the trick.

 

I used the Phoenix Injector system but have also done it by taking a caliper off and pulling the piston out part way then filling the caliper with a syringe. Close the bleeder and push the pistons in slowly. You can gently clamp the line, there are clamps made for this, once the pistons are pushed in, open the bleeder and pull the pistons out, refill and repeat. Watch the overflow at the pump. Don't forget to take the clamp off the line.....

 

 

Edited December 12, 2016 by Boomer343

[dirtrider]

Afternoon littlewimp

 

You either have a controller issue or a pumping issue inside the controller.

 

So no more jump ahead guessing & we can get back to diagnosing the problem in a logical manner.

 

It is possible that you have a bad controller/pump but also possible that you have a control side issue.

 

Just because you got clean fluid out of the control side bleeder fittings doesn't mean that there is no air trapped in the control side.

 

So next question is: does the front brake lever have a firm feel when pulling & can you pull it all the way to the grip????

 

If you can pull the front lever all the way to the grip then you probably still have air in the front control side. (air in the control side won't allow enough pressure build to unseat the apply ball)

 

If you can't easily pull the front lever all the way to the grip then your problem is more than likely inside the ABS controller itself.

 

You DO HAVE brake fluid in both controller resiviours correct?????

 

Also no plug left in the front brake lines????

 

It's possible that with that controller sitting for a few years that the apply ball or piston is corroded or stuck so try pulling the front brake lever vey fast, very firmly, &

as far as possible with the key turned on.

 

If you can't get it working the you can install a used controller but you also have the option of removing the ABS system & reverting to non-power-assist, non-ABS braking (personally I like the non ABS conversion better than the factory power assist braking as it has much better feel & better behaved low speed braking) --If you can live without ABS then a controller removal is a very good (& cheaper) option.

[littlewimp]

Thanks again for your reply's, I shall go through the process of elimination tomorrow evening and report back.

Thanks.

[Sam Taylor]

D.R. is usually always right so go with his advice. Mine is only experiential.

 

That said, you are ahead of the game by replacing the lines regardless, and IMHO ripping out the ABS (or I should say "that generation of BMW ABS"). It's probably the best solution. I'm not even sure I would attempt to "fix" the system as I believe it will eventually fail, this way or that.

 

I miss the concept of ABS, but have not missed that ABS.

 

 

Edited December 13, 2016 by Sam Taylor

[littlewimp]

Thanks Guys, I have made the decision to ditch the abs and fit the braided hoses at the same time, at least then when I'm riding it I know that its not going to give up on me and possibly cause an accident. I located a secondhand unit for £ 300 but decided to just get rid. I don't have ABS on any of my other bikes and its never been a problem,

Thanks Neil.

[littlewimp]

No Turning Back now, I've just been out to my workshop drained all fluid and removed the ABS pump , I'm feeling happier already.

[AndyS]

Well seeing as you have started, I don't think you will be disappointed. I guarantee you will prefer the more linear feel at the handlebar lever. The foot pedal maybe less so. You can improve pedal feel by fitting a smaller master cylinder from the likes of the 1100.

If you would like a pictorial walk-through of a removal procedure, send me an email address.

Andy

[Tourmaster]

cost of a decent R1150RT +- $5K,

cost to fix problematic ABS +- $2K

cost to remove ABS +- $200.00

NEVER having to worry about flashing lights again...priceless

 

YMMV

 

 

[Sam Taylor]

Andy is correct, that back brake will be (or feel) weak.

 

OTOH, I don't take The Road Tool into the dirt much, so in a way I think the balance, unintended though it may be, seems to serve perfectly for the street.

 

Again, experiential.

[eburr]

Sorry, but I respectfully I disagree with the "weak rear brake" comment after manual brake conversion. After hours/days of research, I just completed the process on my Rockster and can attest that not only does the front brake feel absolutely fine (actually better/safer than with servo assist), but so does the rear. Anything more than minimal brake pedal pressure and I can lock it up. Remember, you are supposed to be using 75% front and 25% rear brake pressure anyhow.

 

BTW: Former accident investigator here. I can't tell you how many MC accidents I have seen that were the result of over-use of the rear brake. No need to worry about swapping the rear master cylinder unless you are way more anal than I am, which is pretty friggin' unlikely, or you are used to over using the rear, which is a great opportunity to retrain yourself before it is too late.

 

Rant: The stock servo brake system is dangerous and very well documented as failure prone. Imagine unexpectedly losing 70% of either your front or rear braking ability. It may easily be a fatal design flaw that can only be cost effectively resolved by converting the bike to non-ABS. And I would take a tad (maybe 5% at most?) more rear peddle pressure required and no ABS over an unexpected but almost guaranteed eventual failure that is guaranteed to reduce either the front or rear circuit pressure and available braking by 70%. No comparison in risk. None.

 

Rant done!

Edited December 16, 2016 by eburr

[AndyS]

Sorry, but I respectfully I disagree with the "weak rear brake" comment after manual brake conversion.

 

The reason you don't feel the need to change to a smaller rear brake master cylinder is because your bike already has the smaller one fitted.

 

The 1150RT has a 13mm cylinder (P# 34317660427) and the Rockster has the desirable 12mm cylinder (P# 34317662182).

The 1100RT also uses a 12mm cylinder (P# 34312330456)

 

So the 1150RT will feel very weak at the back brake unless you really push hard.

[eburr]

OK, I did my research and referred back to the BMW parts diagrams. Please take note; the Rockster and the R1150r are largely the same bike with only minor cosmetic, suspension and rear rim and tire differences.

 

1.) Both Rockster and R1150r factory non-abs models share the same 12MM rear master cylinder, part number 34317662182.

 

2.) The Rockster and R1150r factory ABS models both share a larger 15MM rear master cylinder, part number 34317657916.

 

To avoid any further confusion, I converted my 04' ABS Rockster (equipped from the factory with the larger 15MM rear master cylinder bore) to non-ABS. It is exactly the same rear master as the one found on R1150r ABS model bikes. The bike post-conversion brakes well, with no excessive pedal pressure required, and is not notably different in required pedal pressure than another R11150r standard (non-abs) in my shop that was tested and compared against.

 

I stand behind my previous comments that the smaller bore rear master cylinder not necessary to have perfectly decent brakes after the servo-ectomy. Do what you want, but I have ridden both and can honestly say the difference between the manual 13MM master and the Servo equipped 15MM rear is virtually undetectable if both bikes have good pads and rotors, and both have been effectively bled with fresh fluid.

 

Once again and respectfully, how much rear brake are you using anyhow? I have needed to retrain a couple long time friends/riders who were chronic rear brake over-users.

Edited December 16, 2016 by eburr

[dan cata]

Because the rockster always has servo brakes? Is there any rockster bike w/o ABS? Besides being pretty rare, I have never seen one without the servo brake.

 

Dan.

[dirtrider]

Why on earth would BMW use a 12MM rear master on the Rockster ABS and a 13MM on the R1150R ABS? In most other respects they are the same bike. This just doesn't make sense to me. I am OK being wrong, but I am going to look at part numbers now!

 

I could understand the difference in sizes between either factory ABS and non-abs models, but not between the Rockster and the R1150r. Will report back.

 

Morning eburr

 

I don't know about a 12mm rear master cylinder but the later 1150RT's did use a larger rear master cylinder.

 

When removing the ABS system on the later 1150RT's they will stop OK with the 14.29mm rear cylinder but stop a whole lot better with the earlier 13mm rear cylinder. _________________________________________________________

 

In the U.S. 1150RT's above SN ZE 87455 were built with a

revised IABS brake modulator. (ie the original posters 04 1150RT)

 

This new (updated) IABS modulator had revised software to provide for a (stopped vehicle) power saving function.

 

This (revised) IABS function shut down the rear IABS pump

when the engine was at an idle & the bike is at a standstill. (on the RT's, they had enough electrical power usage that added rear brake pump running could drain the battery in heavy traffic, multiple stops, with the brakes held on.

 

The new (updated) brake controller THEN needed a larger diameter rear brake

master cylinder (14.29 mm) instead of the old original (13.00 mm) master to provide enough make-up fluid to provide enough rear brake function in residual braking mode.

 

ALSO-- any IABS controller replacement on the older 1150 RT's required an update to the new larger rear master cylinder.

 

Larger (14.29mm) rear master cyl = much better residual braking reserve fluid capacity--BUT--the later (14.29mm) rear cylinder made for lower rear braking power when the ABS system was removed. So going to the older 13mm rear master cylinder significantly improves 1150RT rear barking when the ABS system is removed.

 

 

 

 

Edited December 16, 2016 by dirtrider

[eburr]

I can't see what you are saying from the available parts diagrams. I will end by suggesting that anyone doing the conversion check out their braking with the existing rear master cylinder first, and then go to the smaller diameter one if they think it necessary. I certainly didn't. Your results obviously may vary!

[dirtrider]

I can't see what you are saying from the available parts diagrams. I will end by suggesting that anyone doing the conversion check out their braking with the existing rear master cylinder first, and then go to the smaller diameter one if they think it necessary. I certainly didn't. Your results obviously may vary!

 

Morning eburr

 

You can't see it in the parts diagram as the information is in a BMW dealer service bulletin.

 

But even so it doesn't sound like you have done more than one BMW ABS removal & even then it is apples to oranges as your bike is not a late model 1150RT.

 

I have a done a number of 11500RT ABS removals & (on the RT) the rear braking difference between the late 1150RT 14.29mm rear cylinder & the earlier 13mm rear cylinder is VERY noticeable.

 

Just keep in mind that the OP here has a late model 1150RT!

[eburr]

Rocksters came in both ABS and non-abs models. In my part of the country the non-abs is more common.

[dirtrider]

Rocksters came in both ABS and non-abs models. In my part of the country the non-abs is more common.

 

Morning eburr

 

The non-ABS rockster came with 12mm rear master cylinder.

[eburr]

My personal ABS Rockster that I deleted the servo from came with the larger bore rear master cylinder I am pretty sure, and it works fine in manual non-assist mode. Feels just like the factory non-abs customer bike in my shop.

[dirtrider]

My personal ABS Rockster that I deleted the servo from came with the larger bore rear master cylinder I am pretty sure, and it works fine in manual non-assist mode. Feels just like the factory non-abs customer bike in my shop.

 

Morning eburr

 

Well, obviously BMW engineering doesn't agree as they released a smaller bore size master cylinder for the rockster non-ABS bikes.

 

 

[eburr]

This is crazy. I am not looking for a war but know what worked for me on my 2004 Rockster. You are right. I have done just one and still recommend just trying it with the existing unit first, and then replace it with a smaller bore master if you feel it is taking too much pressure for your taste. Where in Ohio? I'm in friggin' frigid Ohio.

[AndyS]

Hi eburr,

This forum isn't about slanging matches. It is about sound constructive feedback. Your point is taken, and in this case, an individual considering a Servoectomy may choose to leave their original rear master cylinder in place until they have done all that work. However, a large percentage of us who have performed this on their RT's have come to the conclusion that it is indeed worth changing it.

I lay my cards on the table. I originally did NOT change mine (because I am tight!), however, I did replace it later because I felt that I needed more feel (not power) at the rear brake.

 

[eburr]

Fair enough.

[BoisePilot]

Can anyone supply the part number and or models that used the smaller rear master cylinder? I removed the ABS system on my 2004RT this summer and and I am very happy with the result with the exception of the rear brake feel. It's not bad but more travel and lighter pressure would make for a better feel.

[dirtrider]

Afternoon BoisePilot

 

 

I have always used the early 1150RT 13mm cylinder (P/N- 34317660427)

 

I think Andy uses the 1100RT 12mm cylinder (P/N- 34312330456)

 

If you want the lightest foot pressure & a little more pedal travel then the (P/N- 34312330456) would be the one.

 

You might PM Andy as he is more familiar with using the 12 mm cylinder on the 1150RT than I am. (I haven't ever used the 12mm cylinder on the 1150RT myself)

 

[Sam Taylor]

FWIW, I have a very early 02 1150 RT (Feb 01) and I consider the brake pedal travel, post ABSendectomy, sub-optimal.

 

But I have not swapped it out as I like a weak rear brake and the fronts are so awesome. And I'm cheap.

[eburr]

So please help me to understand exactly which rear master cylinder my 2004 Rockster ABS came with (assuming 13MM vs. the 14.56MM they were superseded to)? When did BMW go to the 14.56MM unit on ABS equipped units?

 

Once again, while I may have done just one ABS removal/conversion, I honestly can't tell the difference in rear brake pedal pressure required and general braking capabilities on my personal and converted bike when compared to a 2003 stock non-abs R1150r in my shop, both with properly serviced systems. Certainly adequate, almost no free-play and stops the bike quite well IMHO, even if used incorrectly (ex: over-used and/or as the primary braking source).

 

From reading through this string, it is my understanding that my 04' Rockster is exactly the same year as the original poster's R1150r, with the only difference in systems being my Rockster came with braided stainless steel brake lines, while a stock R1150r came with rubber. Maybe the difference in lines has resulted in better brake feel with the 13MM rear MC (if that is what I have) than those who have attempted to the same conversion with rubber lines

 

I'm really trying to figure this out.

 

[dirtrider]

So please help me to understand exactly which rear master cylinder my 2004 Rockster ABS came with (assuming 13MM vs. the 14.56MM they were superseded to)? When did BMW go to the 14.56MM unit on ABS equipped units?

 

Once again, while I may have done just one ABS removal/conversion, I honestly can't tell the difference in rear brake pedal pressure required and general braking capabilities on my personal and converted bike when compared to a 2003 stock non-abs R1150r in my shop, both with properly serviced systems. Certainly adequate, almost no free-play and stops the bike quite well IMHO, even if used incorrectly (ex: over-used and/or as the primary braking source).

 

From reading through this string, it is my understanding that my 04' Rockster is exactly the same year as the original poster's R1150r, with the only difference in systems being my Rockster came with braided stainless steel brake lines, while a stock R1150r came with rubber. Maybe the difference in lines has resulted in better brake feel with the 13MM rear MC (if that is what I have) than those who have attempted to the same conversion with rubber lines

 

I'm really trying to figure this out.

 

Afternoon eburr

 

I haven't actually removed the rear M/C piston on the rockster & measured it but my BMW parts manual shows that the rear master cylinder on the 2004 rockster (with I-ABS system) came from the factory with a 15.87mm rear master cylinder.

 

There was a difference in the (OEM) rockster rear brake pad material between the non-ABS & the ABS bike.

[eburr]

Scratching my head here now. I really can't figure out why the rear brake feels so good then with the stock I-ABS rear master cylinder. It honestly feels the same as the non-ABS R1150r in my shop and about the same as my ABS R1100rt. Could it be better? Maybe so, but I am a religious 75% front 25% rear brake user anyhow, and honestly don't want a more sensitive rear brake, especially without ABS.

 

Oh well.

[littlewimp]

All Done, braided lines fitted and bleed, wiring modified, all ready for the summer .

[eburr]

Did you re-use the existing rear master cylinder like I did, or did you change it for a smaller bore? Once again, with stainless steel lines mine feels fine. Just remember; you should be using 75% front brake 75% a brake, and 25% year.

[littlewimp]

Hi Eburr, I stuck with the standard rear master cylinder for now, once I've ridden it and get the feel for it I wont know if I'm happy as is, tbh I tend not to use the rear brake that much unless its raining, saying that I have to use front and rear on my 1955 royal enfield to get it stopped !

[eburr]

Littlewhimp: You probably knew this, but my quote above should have been "75% front and 25% rear".

 

In rain and related slippery conditions, it is very easy to over-apply the rear brake, putting the bike into a skid and possibly resulting in a low-side crash before you even know what happened.

 

One of the biggest mistakes I see newer and/or less experienced riders make is over-use of the rear brake circuit.

Riders really need to train themselves to use both brakes in conjunction almost every time, especially on manual, non-abs and non-linked systems like this conversion (ABS/Servo delete) produces. While these bikes with stock, fully functional ABS/Servo linked braking systems don't require the operator to use both the hand and foot brake to achieve maximum braking results, if one of the circuits fails unexpectedly (which is common on this particular system and the subject of this thread) it is good to know and routinely practice dual control braking to avoid ever skidding the rear tire and losing control. Also, when you go on to ride a non-linked system bike (like a 55' Royal Enfield), it's a skill you will certainly want in your back pocket!

 

I get what you are saying littlewhimp about using the front primarily and that's great, but people, please make sure to use, but not stomp on that rear brake either, especially on wet surfaces and traveling downgrade! A 55' Royal Enfield obviously has a primitive brake system compared to the BMW (dual drum vs. our 3 disk systems) and will never stop like a modern bike, as you are no doubt well aware!

 

I will be interested in hearing how you feel the rear brake functions using the existing master cylinder after your conversion.

 

 

 

Edited January 4, 2017 by eburr