Good morning my friends. I have a new to me 08 Ultra with ABS, and am wondering, even with ABS, if I can flush the old brake fluid out with my Mity Vac in the same manner as you would a non ABS system? Thanks in advance for your replies.

 

Yes! As long as you don't run the master cylinder dry and introduce any air into the system you should have no problem.

 

I don't understand the need to flush brake systems on a harley. I drive cars for many miles without flushing the brake system. I am not saying it is not necessary, I just don't understand why the need.

 

I'm just operating on the assumption that they haven't been flushed in 5 years, and want to do it for good measure.

 

It's recommended to flush & replace brake fluid every 2 yrs by most manufactors including MOCO

 

You will not get the fluid through the the ABS unit without software to cycle it. Flushing/bleeding ABS brakes is best left to the dealer or other with proper software. And, Yes, flushing ABS brake fluid is a good idea. Not only because of condensation plus heat cycling, but because it can become electrically charged and cause corrosion.

 

Not sure about all that. When I bled by brakes at the two year point, I installed speedbleeders and it was a one man job. I was able to push the discolored brake fluid out and ultimately it cleared up and was looking the same as the new DOT 4 fluid I was pouring into the reservoirs.

I would assume that is has to go through the ABS module to make it to the front or back caliper nipples, but maybe not. I know that if for some reason you get air into the ABS module, the dealer must use the digital technician to cycle the abs module in order to ultimately bleed the air out of the unit.

 

Worth a flush every 3-4 years with a caliper overhaul. improves braking efficiency.

 

Okee Dokee ... Here's the reason for flushing your brake fluid ... Brake fluid is Hygroscopic, ( http://en.wiktionary.org/wiki/hygroscopic ) that means it absorbs moisture from the atmosphere. No matter how effectively you think you have the system sealed up, this is going to happen. The moisture that is absorbed has a lower boiling point than the brake fluid hence, when the fluid is heated, ( by heat generated from stopping ) it will boil and then "gas out" and evaporate leaving ( minimal amounts ) of air in the system leading to a soft/spongy pedal or lever. Also when the moisture is trapped in the system it is corrosive, leading to premature failure of the seals and metal parts within the system. By flushing the fluid ( at least every other year ) you are inhibiting the process and prolonging the components of your hydraulic braking system.

 

While fluid does go through the the ABS Module, the fluid that is in the ABS solenoid can only be bled/flushed by electronic cycling. At least that is how I understand it?