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OEM Brake Line Replacement

bobr9

143439
99 R1100RT

I am about to start the job of replacing my OEM brake lines with stainless from Galfers. My question: Is there a special procedure to be followed for re-filling and bleeding the brake system from a completely empty state as opposed to the procedure used for normal bleeding with fluid already in the system?
Any help, guidance, or references to this type of procedure would be appreciated. Thanks...Bob
 
You don't have to empty the master cylinders completely and I suggest you don't pump all the fluid out.

I went to a medical supply place and bought myself the largest syringe they had and some taigon tubing suitable to fit onto the bleeder screws. Clamp the tubing onto the syringe. Warm it up to stretch it if you have to. Speed Bleeder sent me some nice stretchy silicone type tubing when I bought bleeders there once that works well for this. I've since put my OEM bleeders back on though since I changed my bleeding method. You need lots of rags or paper towels no matter how you do this and I cover all areas of the bike below the masters with lots of rags just in case of a drip. They happen...

Once everything is together suck up the new fluid up into the syringe and tubing, then hold the rig upside down and push all the air out. Don't worry about air in the syringe. It will rise up when you pump it in.

Attach the tube carefully as you can to not allow any air in to the bleed screw and open the bleeder. Pump the fluid in. You will have to do this several times while removing any old fluid from your master reservoir as you go.

Replacing the brake fluid from the bottom up instead of pumping it down with the master was the only way I could totally bleed the air out of my system after installing new lines. It works so well that I will do annual brake fluid replacement that way from now on.

Way easier to push bubbles up rather than down. I think I was doodling during the physics class that explained why air rises so easily in liquids. :laugh
 
Hmmm...interesting. So, maybe a stupid question, but how did you drain the system in the first place if you do not empty the master cylinder? Also, why did you elect to remove the speed bleeders? Thanks
 
Hmmm...interesting. So, maybe a stupid question, but how did you drain the system in the first place if you do not empty the master cylinder? Also, why did you elect to remove the speed bleeders? Thanks

Not a bad question at all. Remove the brake lines only from the bottom up and have rags at the ready to catch the small amount of fluid they contain. A jar or other suitable container can be used to catch the rest when you take the top end off. At that point the lines will drain completely on their own.

You can also just pump out all the fluid including the masters if you want to and catch all the fluid from the bleeder screws which is less messy but will take longer to refill and bleed out.

Either way, filling from the bottom up like the factory did is much easier and quicker when it comes time to get the air out.

I removed the speed bleeders because you cannot pump fluid back into the system through them. There is a spring loaded ball in them. This makes the speed bleeder a one way valve and the fluid can only be pumped out from the master.
 
A MityVac will save you a lot of aggravation on this project. Bleed from the calipers and from the ABS modules. There's no trick to it that I've ever found. I just bleed and bleed, and eventually the lever firms up.
 
If you fill them from the bottom up, you will still need to burp the calipers at the bleeder to get that last little bit of air out of them.
The bleeder is on the highest point of the caliper. Its the only way to get the air out.

The bleeder is higher up than the line going in, so you can't push the air down into the line going in the caliper. Just look at it.

I would loosen one line, hold the brake lever in (front or rear) by hand or bungee and replace the line. THEN pump the lever and bleed as normal. Things should work out fine. Don't ever let the master cylinder get empty or suck air. It should be no big deal. If the master cylinder does suck air, you just have to start over.

Using a clear tubing in a glass jar from the bleeder is one way to see what is going on. Don't be shy about pumping the lever. Being a little aggressive will push the air through the system.

Just a little air makes the lever feel mushy.

David
 
If you haven't started the job, send back the Galfers and order the Spieglers. The line from the ABS down to the the T fitting is not labeled correctly and is a poor design. I did not discover the problem until I had all the other lines on the bike. Galfer customer service was worthless in helping resolve the problem. Spiegler on the other hand made up a single, properly designed line that I fitted up to the bike without any further problems.

Galfer
small.jpg

Galfer at T
small.jpg


Spiegler top Galfer bottom
small.jpg

small.jpg
 
I have been a fan of the "Happy Wanderer Method" (tm) for about 20 years. Works first time, every time. Its never failed me. Ever.
 
If you haven't started the job, send back the Galfers and order the Spieglers. The line from the ABS down to the the T fitting is not labeled correctly and is a poor design.

How long ago was this? My line appears to be a different design than the one you have shown, so maybe Galfer has redesigned it? Hope so. Thanks for the input and heads up though. I'll take a very careful look when I get the tupperware off and am able to see the routing.
 
Yep. I found some 60 cc/mL syringes at a local Medical Supply joint for $1.99 each.
I always start by sucking up the old fluid out of the master(s) with an old turkey baster.
Rags, rags, and more rags. Or paper towels. Cover everything that even looks like it _might_ get a drip on it. Old towels work well for this especically up top for the tank etc.
 
How long ago was this? My line appears to be a different design than the one you have shown, so maybe Galfer has redesigned it? Hope so. Thanks for the input and heads up though. I'll take a very careful look when I get the tupperware off and am able to see the routing.

I replaced mine about a year ago. It sounds like they corrected the kit since then - good for Galfer.
 
Has anyone done this with speed bleeders already installed in the front calipers? I have replaced the front lines and am getting ready to bleed the system. Speed bleeders were already installed on the front calipers. I just watched a video which stated that they should not be used for the initial fill and bleed after line replacement as the air may prevent developing enough pressure to overcome the spring in the check valve. They recommend using the OEM bleed screws to get an initial fill and bleed, then switching to the speed bleeders, however I do not have the OEM bleed valves.
 
You don't have to empty the master cylinders completely and I suggest you don't pump all the fluid out.

I went to a medical supply place and bought myself the largest syringe they had and some taigon tubing suitable to fit onto the bleeder screws. Clamp the tubing onto the syringe. Warm it up to stretch it if you have to. Speed Bleeder sent me some nice stretchy silicone type tubing when I bought bleeders there once that works well for this. I've since put my OEM bleeders back on though since I changed my bleeding method. You need lots of rags or paper towels no matter how you do this and I cover all areas of the bike below the masters with lots of rags just in case of a drip. They happen...

Once everything is together suck up the new fluid up into the syringe and tubing, then hold the rig upside down and push all the air out. Don't worry about air in the syringe. It will rise up when you pump it in.

Attach the tube carefully as you can to not allow any air in to the bleed screw and open the bleeder. Pump the fluid in. You will have to do this several times while removing any old fluid from your master reservoir as you go.

Replacing the brake fluid from the bottom up instead of pumping it down with the master was the only way I could totally bleed the air out of my system after installing new lines. It works so well that I will do annual brake fluid replacement that way from now on.

Way easier to push bubbles up rather than down. I think I was doodling during the physics class that explained why air rises so easily in liquids. :laugh

:thumb
 
Has anyone done this with speed bleeders already installed in the front calipers? I have replaced the front lines and am getting ready to bleed the system. Speed bleeders were already installed on the front calipers. I just watched a video which stated that they should not be used for the initial fill and bleed after line replacement as the air may prevent developing enough pressure to overcome the spring in the check valve. They recommend using the OEM bleed screws to get an initial fill and bleed, then switching to the speed bleeders, however I do not have the OEM bleed valves.

see post #4 above.
 
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