How many cycles to flush ABS HCU?
#11
08-10-2017, 06:30 PM
#12
08-10-2017, 06:43 PM
Road Captain
Ok. This may sound stupid. But wondering if it would work. Put bike on jack. Flush system like normal. Now take about 30 feet of string place it taped onto center of rear tire rolling tire and wind up backwards taping every so often to keep it centered to make it like a pull (recoil start like) from bottom of tire. Turn ignition on. Get someone to press front brake as you open bleeder. Get a kid to run straight back pulling the string and spinning the rear tire. The system recognizes the rear tire spinning and front not spinning then abs kicks in pumping. Wondering if this would work.
#13
08-10-2017, 08:48 PM
Road Warrior
Your right, that does sound stupid ! Basically removing fluid from reservoir with syringe and cracking bleed screws to flush, never let reservoir get low. I had a BMW R1150RT a while ago with the complicated wizzy brakes and there was sequence to follow plus a special funnel. I bet You Tube has some videos on this.
#14
08-11-2017, 06:08 AM
Seasoned HDF Member
Ok. This may sound stupid. But wondering if it would work. Put bike on jack. Flush system like normal. Now take about 30 feet of string place it taped onto center of rear tire rolling tire and wind up backwards taping every so often to keep it centered to make it like a pull (recoil start like) from bottom of tire. Turn ignition on. Get someone to press front brake as you open bleeder. Get a kid to run straight back pulling the string and spinning the rear tire. The system recognizes the rear tire spinning and front not spinning then abs kicks in pumping. Wondering if this would work.
#15
08-11-2017, 08:46 AM
Road Warrior
I just replaced the brake fluid on my 15 Limited. I know the dealer uses the Digitial Tech thingy or whatever it's called to flush out the HCU. Since I am doing this myself, I am asking how many times should I activate the ABS to get the new fluid in and old fluid out of the HCU? I am planning on changing the brake fluid again after the HCU is flushed out. I sleep a lot better when I can avoid going to the dealer for anything.
This whole activating the ABS unit in my opinion is nothing more then once again, INTERNET forum talk. Just like motor oils, its all BS.
Bottom line, bike manual calls for brake fluid change every two years, nothing more then that, no special wording that the "dealer" must do it, ya da ya da but you have people in the forums saying this ABS crap and people going "oh my, I never thought of that"
BS. if and ONLY if some fluid in the ABS unit some how doesnt get flushed out, big deal, brake fluid absorbs moisture so any little tiny bit of moisture that MIGHT be in any little tiny bit of old brake fluid will be dried out/absorbed by the new fluid.
Brake fluid doesnt EVER break down like oil does, it gets changed because it absorbs moisture.
Anyway, that is my feelings on the matter *L* ... and I will simply flush every two years.
The following users liked this post:
robbie52 (08-18-2017)
#16
08-11-2017, 11:05 AM
#17
08-11-2017, 12:06 PM
I too would like to know why a simple power bleeder can't be used? Been doing it that way on cars for years!
#18
08-11-2017, 10:53 PM
Extreme HDF Member
I go several weeks then flush again. Each time the engine is started it does one cycle of the ABS system so I suspect that is sufficient. It has worked. (so far)
Motorcycle ABS systems face different conditions than automotive systems. First they operate in a hotter environment and have a tiny volume of fluid in comparison.
And yes proper flushing of H-D's system is a H-D must. Just bleeding the brakes with a vacuum pump does not access any of the fluid in the ABS module. The digital tech rapid fires it until fully flushed.
It is simply a smart thing to do.
Motorcycle ABS systems face different conditions than automotive systems. First they operate in a hotter environment and have a tiny volume of fluid in comparison.
And yes proper flushing of H-D's system is a H-D must. Just bleeding the brakes with a vacuum pump does not access any of the fluid in the ABS module. The digital tech rapid fires it until fully flushed.
It is simply a smart thing to do.
Last edited by lh4x4; 08-11-2017 at 10:59 PM.
#20
08-12-2017, 07:15 AM
Doing it yourself is the ONLY way to be sure it was done right - or done at all, for that matter.
No confidence at all in dealership "techs", especially where the MOCO's concerned!
I believe that there's a hand-held gadget available online that's the same as the one the dealerships use.
No confidence at all in dealership "techs", especially where the MOCO's concerned!
I believe that there's a hand-held gadget available online that's the same as the one the dealerships use.