What is the fluid "circuit" during an ABS activation in a CLOSED SYSTEM? If the released fluid is pumped in a circle, it winds up back inside the HCU. However, if it is flushed away during an OPEN SYSTEM activation with the Harley computer, it is truly changed. Personally, I have NO IDEA where the fluid goes, just asking the question for the guys who do the flush, then ride and activate the system, and flush again. That idea sounds great IF you know the old fluid is pumped into the brake lines and can be emptied with the second flush. Personally, I don't see how that would work, the fluid in the brake line hardly moves, the PRESSURE is relieved momentarily, but the fluid doesn't circulate.

 

my dealer measures the brake fluid (specific gravity? acidity?) and puts that on your service receipt, so you can predict when the brake fluid will erode the ABS module.

this is just another 'Pay to Play" until StoneCold develops an ABS module for the forum....

 

It measures moisture content. You can buy the tool on Amazon for like $20.

 

…..Until they don't. Have your ABS flushed every 2 years, its not a big deal.

 

When purchasing my King in 09 I decided on cruise and theft deterrent but not the ABS. My reasoning was that it could be a added area of trouble and that I really did not need it. Boy, what lame thinking that was. Good or bad that it is, this can be a potentially life saving tool or at least help prevent loss of control. So all that I would like to add is that be glad that you have it and keep it operational to the best of your ability. Any of the above bleeding procedures are positive so take your pick.

 

I'm with you on this. Those are my thoughts exactly. I don't know the particulars on how the system works either and I doubt that most of us on here do. Between my 09 and my 16, (125 kmiles total) the brake fluid has been changed 4 times. I let the dealer do it the first time and I wasn't happy with the cost. I did it myself by flushing the fluid then riding and triggering the ABS front and rear several times then flushing the systems again. I never had any problems. Now with linked brakes and stuff I don't understand, I found that my local indy does it for a reasonable charge ($150 for the brakes and clutch) so he's gonna get the job from now on unless it's proven that another do it yourself method will work fine, which I doubt.

 

+1 When I bought my 09 I asked for ABS. The salesman tried to push me away from it, asked me why I wanted it. He steered me to the exact same bike w/o ABS. When I said I wasn't going to buy a bike without ABS he said they didn't have one in stock, so I had them bring one in from another dealership. I know in my own heart ABS has saved me from at least serious injury and probably death 2 times.

 

You can successfully change all ABS fluids with just a little extra effort.

Drain front and rear as always. Then turn the ignition on and off many times. That is what the digital tech does but in rapid fire. Every time the ignition is turned on the ECM test fires the ABS.

Another method is to ride the bike for awhile. After either method drain and refill the two master cylinders. Keep the H-D $100 in your pocket. I have done these two methods many times on many ABS H-D's since 2010. Failures are at Zero.

The using ADS hard to activate may not be totally necessary as the normal application goes through the system under normal use. Just follow the lines they do not go from the master to the slave cylinder. They pass through the system to each one.

Every time you turn the ignition on and every time you use the brakes hard to activate the ABS the new fluid replaces the supply in the ABS system. Use that knowledge to your benefit.

I get the 1 quart DOT 4 at Walmart for about $8 and it will do 8 to 10 bikes. One heck of a long way from $100 per bike per H-D service dept.

 

For those that think the master cylinder just adds pressure and fluid does not flow seem not to understand that the pressure has flow when it pushes (moves) the piston out to move the pad out. That amount of fluid does not flow backward when the lever is released it flows to the master cylinder. Every time all the time. So after awhile all of the fluid cycles back to the master cylinder.

 

How does the fluid from the brake caliper get back to the master cylinder? There's only one line for each caliper.