[Stan83402]

The good news is that I found, while doing a pre-ride inspection, a slight leak in the right front brake hose just above the caliper.

So, I am about to start my first major repair on my 02 K1200LT just when the really good riding season is about to start here in Idaho -bummer. I have had her 6 months and have logged 3000 miles.

I have spent the last few hours reading and downloading all the info I could find on this site. Looks like I will be removing the tupperware (for the first time) and replacing all the brake lines - I know, easier said than done. I don't have a Clymers Manual - does it provide directions for what I am going to do? I noticed on Amazon and other sites there seems to be different versions covering a 02 LT ie. M501-1, M501-2, M501-3. Does it matter which one?

Thanks

 

[jzeiler]

The Clymer does not tell you how to bleed the system of air once you replace the lines but rather refers you to the dealer. It is not a simple task but doable for the average mechanic with some tips and instruction. There are two separate circuits for both front and rear the fluid does not mix or flow between them. Many here have done this task with great success so there are support resources here should you choose to do the job.

 

[jrlakin]

I am sure in the Hall of Wisdom there is a post somewhere for the procedure to "bleed" the system. I, with the significant help of one of my friend (Billd) on here, just replaced my brake lines on my 2000 LT, along with replacing the ABS unit. The 99-01 have a different ABS system, and are much easier to do. However, two years ago we also replaced the ABS unit on my 05 GS which has a similar servo assist system, and I am sure we found the instructions on here.

 

[smahon]

Well, here is my $0.02. I just did all the brake lines on my '05 using info from this site and an excellant video by John Z. I replaced mine with Spieglers and I'm happy with them. That being said, if I had to do it again, I would *not* replace the two brake lines on the control circuits. These are the lines from the hand and foot levers to the ABS unit. Those two lines were such a PITA and the fluid in them was virtually clear. Neither of these lines are under much pressure, even when hard braking, and I just don't feel it was worth the time it took to replace them and then bleed the air out of those circuits. It made a mess and just took too much time. BTW, these lines are much easier to flush if you haven't changed the brake lines.

The wheel circuits, on the other hand, were much easier to replace, had very dirty fluid, and were a snap to bleed. Much bigger bang for the buck/time IMO.

 

[Voyager]

I am sure in the Hall of Wisdom there is a post somewhere for the procedure to "bleed" the system. I, with the significant help of one of my friend (Billd) on here, just replaced my brake lines on my 2000 LT, along with replacing the ABS unit. The 99-01 have a different ABS system, and are much easier to do. However, two years ago we also replaced the ABS unit on my 05 GS which has a similar servo assist system, and I am sure we found the instructions on here.

Here is the instruction procedure I just used today to flush my brakes.

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

I also bought and watched John Zeiler's video and that was helpful also, but is somewhat incomplete as John did not bleed all three ports for the control circuits as described in the BMW manual and the manual at the link above.

It is a pain doing the full procedure and I spend nearly 6 hours doing this (and that was with the tupperware already removed at the start), but it was my first time, I was making the special "tools" such as the spacer blocks, and I just don't move that fast anymore!

However, all appears to have went well, but I was surprised to get a fair bit of air out of the rear control circuit. This was surprising as I was only flushing the system, and had no lines opened or replaced. I can't imagine the air being in the system and not having brake troubles or a fault code, but I get several bubbles out of the rear control circuit when bleeding the first port in the sequence. However, after bleeding ports 2 and 3 adn then coming back to 1 for the second bleed (again per the manual above), the air was mostly gone and only got a bubble or two the second time.

 

[jzeiler]

I also bought and watched John Zeiler's video and that was helpful also, but is somewhat incomplete as John did not bleed all three ports for the control circuits as described in the BMW manual and the manual at the link above.

The video is designed to cover just the flushing of old fluid with new while not letting any air in which would require a bleed. As you found out the bleed is a bit more complicated.

Maybe I need to do a bleed video as well just need some donor bikes that want to replace their brake lines.

 

[Voyager]

The video is designed to cover just the flushing of old fluid with new while not letting any air in which would require a bleed. As you found out the bleed is a bit more complicated.

Maybe I need to do a bleed video as well just need some donor bikes that want to replace their brake lines.

It wasn't clear to me from reading the BMW manual and other sources, if flushing through the control circuit port was sufficient to remove all of the old fluid. I recall reading somewhere that if you don't also flush through the integral and metering ports you leave some amount of old fluid in the system. However, I am far from certain as I have never taken a BMW ABS unit apart to see what is inside. Something I will do some day if mine ever dies. It would be fun to see the inside up close and personal.

 

[jzeiler]

Yeah originally BMW had you flush all three for each side but I never got much dirty fluid out . Then a bulletin came out reducing the requirement (as a cost saver) that reduced it to the one tall nipple. I never got as much as a quarter inch of dirty stuff out of the other ports. I had one apart the other day not much area for fluid in those ports.

 

[Voyager]

Yeah originally BMW had you flush all three for each side but I never got much dirty fluid out . Then a bulletin came out reducing the requirement (as a cost saver) that reduced it to the one tall nipple. I never got as much as a quarter inch of dirty stuff out of the other ports. I had one apart the other day not much area for fluid in those ports.

Thanks, John, Iwas not aware of that bulletin and didn't come across it during my searching. It wasn't clear to me how much of a benefit this was, but I figured it was good practice if nothing else. At 5 years of age, my LT will likely need new brake hoses in a few more years so knowing how to do a full bleed can't be a bad thing.