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2013 RT Brake Line Replacement

pappy35

Member
In my quest to find the perfect ergonomics on my RT I just installed a set of Illium Works Barbacks which necessitated the installation of a slightly longer front brake line. I've bled the brakes before and have a GS-911. While I was at it I installed Speed Bleeders all around. This work got me wondering about how the ABS actuator works and what the GS-911 procedure actually does.

1) iABS and the GS-911:
The brake fluid runs from the master cylinder through the ABS actuator to a splitter that appears to be inside the lower fork brace and from there to each caliper. When I run the GS-911 ABS 'bleed' function, the system activates and the brake lever slowly bottoms out, I hold for two seconds, release and repeat. What does this actually do? With the brake handle movement, it would seem to me that the brake fluid in the master has to go somewhere but there's no return line so where does the fluid I'm pumping go? I feel like there's something important happening here that I'd like to try to understand better.

2) Bleeding the master cylinder:
The front brakes have always felt a bit spongy (especially as compared to the rear). I can stop just fine. There's no fade. Really nothing about the brakes worry me but the slight sponginess doesn't seem right. There is no bleeder on the front reservoir, how does one check to make sure there's no air trapped up top?

3) Speed Bleeders weeping:
I installed the speed bleeders which come with thread sealant applied (I also bought a bottle for future use). Per the GS-911 procedure, one bleeds, closes, then rebleeds the system after the test. I noticed that during the post-testing bleed they were weeping a very small amount of fluid around the threads. Is this normal? Surely I don't have to apply thread sealant at each use as that would reduce their usefulness.
 
following this...

in my experience on my 13RT, i have never used the GS911 to bleed the brakes...and i flush them at least yearly...and i have never used "speed bleeders" on any motorcycle i have owned, never saw the need...i attach a bleed hose to a container, looping up then down, simply slightly crack open the bleed valve, gently pump the master cylinder (either front or back) and maintain the fluid level in the reservoir, protecting the paint work with towels...right caliper first, then left...continue until the brake fluid is clean...rear is easier, same procedure...

changing brake lines adds a bit of hassle but no much...FTR, i fabricate my own brake lines when required...just did on my 15 S1000R to make using a triple clamp stand possible...:dance

flushing both takes me about 15 min....

the GS911 IS required on the "whizzy brake" versions though....giant PITA to flush them...:banghead

wyman
 
I went with speed bleeders mainly because I'm a one-man operator with respect to vehicle maintenance and I find the reach to the left-side caliper such that it's pretty difficult to watch the drain tube for bubbles (or fluid color change) while simultaneously pumping the brake and opening/closing the nipple. My questions were more about theory (why does the brake handle depress during that test and and where does the fluid go and how does one ensure there's no air trapped up by the master) than about the steps needed to bleed the system. My brain works by understanding how a system works more than by simply learning steps in a process. It's a curse but one that's served me well in my engineering career. I do appreciate your response though. Thanks.
 
I went with speed bleeders mainly because I'm a one-man operator with respect to vehicle maintenance and I find the reach to the left-side caliper such that it's pretty difficult to watch the drain tube for bubbles (or fluid color change) while simultaneously pumping the brake and opening/closing the nipple. My questions were more about theory (why does the brake handle depress during that test and and where does the fluid go and how does one ensure there's no air trapped up by the master) than about the steps needed to bleed the system. My brain works by understanding how a system works more than by simply learning steps in a process. It's a curse but one that's served me well in my engineering career. I do appreciate your response though. Thanks.

i, too, am a one man operation....:thumb
 
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