Results 1 to 15 of 18

Thread: Value of replacing most of the brake fluid in a 2004 RT?

Hybrid View

  1. #1
    Registered User
    Join Date
    Sep 2007
    Posts
    3

    Value of replacing most of the brake fluid in a 2004 RT?

    I like to use the local motorcycle shop for routine service work. They have done a routine motorcycle brake fluid change, which changes out most of the fluid in the front and rear brake lines. I did this before I realized you need to remove the gas tank to access all 3 circuits since it has power brakes. It is time consuming and expensive ( I would need to go to a dealer) for me to properly change the brake fluid.

    My question; how much value is there in a "routine motorcycle" brake fluid change as compared to changing out 100% of the fluid? I am not a mechanic, but I am assuming all 3 circuits have to communicate and by removing the fluid in both the front and rear reservoirs, front and rear brake lines and calipers, you are removing most of the old brake fluid?

    I am guessing people have been either intentionally or unintentionally doing this for years. And I realize it is not the ideal solution, but it is a compromise, and a lot better than not changing out the brake fluid at all.

    Thanks for any opinions.

  2. #2
    Jammess jammess's Avatar
    Join Date
    Aug 2005
    Location
    Florence, OR.
    Posts
    617
    Quote Originally Posted by Thomsen View Post
    I like to use the local motorcycle shop for routine service work. They have done a routine motorcycle brake fluid change, which changes out most of the fluid in the front and rear brake lines. I did this before I realized you need to remove the gas tank to access all 3 circuits since it has power brakes. It is time consuming and expensive ( I would need to go to a dealer) for me to properly change the brake fluid.

    My question; how much value is there in a "routine motorcycle" brake fluid change as compared to changing out 100% of the fluid? I am not a mechanic, but I am assuming all 3 circuits have to communicate and by removing the fluid in both the front and rear reservoirs, front and rear brake lines and calipers, you are removing most of the old brake fluid?

    I am guessing people have been either intentionally or unintentionally doing this for years. And I realize it is not the ideal solution, but it is a compromise, and a lot better than not changing out the brake fluid at all.

    Thanks for any opinions.
    You know it sounds like maybe your shop is treating your 1150 like an older and simpler 1100 with ABS. On my '94 R1100RSL it is not necessary to remove the tank and directly bleed the ABS modulator just bleed and flush the brakes by using only the front and rear wheel bleeders. Needless to say I like the ABS on my '94 much more than the system that WAS on my '04 1150RT. Notice that I use the word "was" as a couple years ago the entire ABS system somehow just disappeared from my '04. Odds are I will regret having removed the ABS system from the '04 when I attempt to sell the big top heavy beast.
    Jammess

  3. #3
    Pepperfool GSAddict's Avatar
    Join Date
    Feb 2008
    Location
    Sechelt, British Columbia
    Posts
    1,297
    Quote Originally Posted by jammess View Post
    You know it sounds like maybe your shop is treating your 1150 like an older and simpler 1100 with ABS. On my '94 R1100RSL it is not necessary to remove the tank and directly bleed the ABS modulator just bleed and flush the brakes by using only the front and rear wheel bleeders. Needless to say I like the ABS on my '94 much more than the system that WAS on my '04 1150RT. Notice that I use the word "was" as a couple years ago the entire ABS system somehow just disappeared from my '04. Odds are I will regret having removed the ABS system from the '04 when I attempt to sell the big top heavy beast.
    Correct, but if you really want to get ALL the fluid changed, you must still remove the tank and pull some fluid thru both bleed nipples at the top of the ABS unit itself. (ABS II units)
    '
    Ufda happens..........

    It's all about the details.

  4. #4
    Pepperfool GSAddict's Avatar
    Join Date
    Feb 2008
    Location
    Sechelt, British Columbia
    Posts
    1,297
    Quote Originally Posted by jammess View Post
    You know it sounds like maybe your shop is treating your 1150 like an older and simpler 1100 with ABS. On my '94 R1100RSL it is not necessary to remove the tank and directly bleed the ABS modulator just bleed and flush the brakes by using only the front and rear wheel bleeders.
    Correct, but if you really want to get ALL the fluid changed, you must still remove the tank and pull some fluid thru both bleed nipples at the top of the ABS unit itself. (ABS II units)
    '
    Ufda happens..........

    It's all about the details.

  5. #5
    Jammess jammess's Avatar
    Join Date
    Aug 2005
    Location
    Florence, OR.
    Posts
    617
    Quote Originally Posted by GSAddict View Post
    Correct, but if you really want to get ALL the fluid changed, you must still remove the tank and pull some fluid thru both bleed nipples at the top of the ABS unit itself. (ABS II units)
    I agree that it certainly doesn't hurt a thing to pull the tank, and on an RSL it is certainly easier than on an '04RT, and open the two modulator bleeders but since the fluid is common to the wheel circuits I think it is not necessary as you can do a complete system flush without touching the two hidden bleeders. Now, I do bleed the hidden bleeders because I do get a few small air bubbles out this way and I do want to avoid the ABS warning lamps and doing a job twice. One thing I can't stand is having to do the same work over because I skipped over something. That really irritates big time.
    Jammess

  6. #6
    . AntonLargiader's Avatar
    Join Date
    Jul 2004
    Location
    Charlottesville, VA
    Posts
    1,372
    Your shop doesn't know how these brakes work, and that is dangerous. They have not 'changed out most of the fluid' at all, and they have possibly left you with a system that might shut down.

    I assume that they changed the fluid in the external reservoirs and then bled a bit of fluid from the calipers. Those two circuits are totally separate. The fresh fluid in the external reservoirs will never go beyond those reservoirs, and the fluid that they bled from the caliper has not been replaced, meaning that the internal reservoirs are now low. You need to get this fixed by someone who knows the system (doesn't have to be a dealership, and it could be you if you are willing to learn about it and do the work).
    Anton Largiader 72724
    largiader.com bmwra.org

  7. #7
    Registered User
    Join Date
    Nov 2007
    Location
    Joplin, MO
    Posts
    950
    Quote Originally Posted by AntonLargiader View Post
    Your shop doesn't know how these brakes work, and that is dangerous. They have not 'changed out most of the fluid' at all, and they have possibly left you with a system that might shut down.

    I assume that they changed the fluid in the external reservoirs and then bled a bit of fluid from the calipers. Those two circuits are totally separate. The fresh fluid in the external reservoirs will never go beyond those reservoirs, and the fluid that they bled from the caliper has not been replaced, meaning that the internal reservoirs are now low. You need to get this fixed by someone who knows the system (doesn't have to be a dealership, and it could be you if you are willing to learn about it and do the work).
    +1000. You now have a dangerous situation.

    the bleeding instructions are found here

    http://advwisdom.hogranch.com/Wisdom/service_abs3.pdf

    or on a CD that Jim sells. It is really fairly easy. I did a braided brake line upgrade and it was the easiest bleeding job I ever did. I really like the system and with the cost of the replacement, you really want clean fluid with good corrosion inhibitors in it.

    Rod

  8. #8
    Registered User
    Join Date
    Sep 2007
    Posts
    3
    Quote Originally Posted by ragtoplvr View Post
    +1000. You now have a dangerous situation.

    the bleeding instructions are found here

    http://advwisdom.hogranch.com/Wisdom/service_abs3.pdf

    or on a CD that Jim sells. It is really fairly easy. I did a braided brake line upgrade and it was the easiest bleeding job I ever did. I really like the system and with the cost of the replacement, you really want clean fluid with good corrosion inhibitors in it.

    Rod
    Thanks for responding. I have viewed the instructions several years ago and decided this was a bit more than I was willing to get into. I will review them again. When I inadvertently had the incorrect procedure done, the brakes performed well, but maybe I just got lucky for 2 years. And I have since had the correct procedure performed. So the 3 circuits don't communicate with each other as was written earlier? And the majority of the brake fluid volume is in the center circuit?

  9. #9
    Registered User
    Join Date
    Jun 2012
    Posts
    213
    Deleted my original reply - even with a disclaimer it might be a disaster.

    I could not believe the reply from AntonLargiader so I tried to find more information.

    I found a diagram:
    bmw_integral_abs_p0034934-b.jpg

    ...and changed my opinion.

    My opinion now is that's a really stupid design and if it were on my bike I would find a way to get rid of it.

    The circuits appear to be isolated hydraulically from each other.
    The circuits that actually do the braking use two separate reservoirs which are hidden under the tank.
    If you bleed fluid from the caliper you deplete that reservoir.
    Furthermore (I haven't read the procedure yet) it appears that in order to bleed the air out of the control side of the system, that has to be done under the tank as well.

    Frankly I wouldn't trust ANYONE to work on these for me unless I was standing there watching them.

    If you lose electrical power to the system the brakes should still work with manual pressure.
    However if you allow the power side of the system to get too low on fluid you'll have no brakes.
    Surely there is a sensor or something to warn you ??? of your impending death ???

    Hidden reservoirs? Requiring the tank be removed? With no visible level indication? Evil.
    Since manual pressure can be passed through - I would think you could re-plumb around the Evil directly to the calipers.

  10. #10
    . AntonLargiader's Avatar
    Join Date
    Jul 2004
    Location
    Charlottesville, VA
    Posts
    1,372
    Quote Originally Posted by scott.lambert View Post
    I could not believe the reply from AntonLargiader so I tried to find more information
    ....
    Frankly I wouldn't trust ANYONE to work on these for me unless I was standing there watching them.
    Scott,

    I just have to wonder about this. If you knew nothing about the system before, how is it that you are going to supervise and check the work of someone who is professionally trained on it?

    This system has been around since the turn of this century. It's nothing new to trained mechanics.
    Anton Largiader 72724
    largiader.com bmwra.org

  11. #11
    Pepperfool GSAddict's Avatar
    Join Date
    Feb 2008
    Location
    Sechelt, British Columbia
    Posts
    1,297
    Quote Originally Posted by AntonLargiader View Post
    Scott,

    I just have to wonder about this. If you knew nothing about the system before, how is it that you are going to supervise and check the work of someone who is professionally trained on it?

    This system has been around since the turn of this century. It's nothing new to trained mechanics.
    Welcome to the internet Anton, it's full of experts.
    '
    Ufda happens..........

    It's all about the details.

  12. #12
    Registered User
    Join Date
    Jun 2012
    Posts
    213
    Quote Originally Posted by AntonLargiader View Post
    Scott,

    I just have to wonder about this. If you knew nothing about the system before, how is it that you are going to supervise and check the work of someone who is professionally trained on it?

    This system has been around since the turn of this century. It's nothing new to trained mechanics.
    I'll have you know I have been full of crap for much longer than that. Since at least 1982.

    I think what I meant to say was that the system is intrinsically dangerous and that knowing what little I have learned about it in the past 20 hours, I would not trust anyone but myself to work on my servo brakes. I would learn all there is to know about it and I would work on it myself.
    I know that's not fair and not reasonable for normal people.

    The OP took his ride to a "local motorcycle shop" - maybe not trained on BMWs.

    The design really bothers me. If you remove fluid from the powered side, fluid leaves the visible reservoirs on the control side.
    Without specialized training, even if you traced the lines under the tank, you'd be within your rights to assume that this fluid came from that circuit.
    There's nothing under there that looks like a reservoir.
    How many of these are out there getting the "routine" service from shops like this?

    I'm not all up in arms about it, I have an 1100 with the Brembo system and I like it just fine.
    It will loft the back tire if I mash on it - I think you can't really stop harder than that without retro rockets.
    I feel like the servo system is an answer looking for a question. A horribly complex answer.

    Godspeed with your whizzy brakes. I'll have none of it.

Tags for this Thread

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •