Why you should flush your brake fluid properly

[Jetfixer]

The factory recommended interval for brake fluid flushing is every 2 years. Yes, of course you can bleed the brakes the old fashioned way, one wheel at a time. However, there is no way to bleed the ABS unit without hooking up to BUDS/BUDS2. During the procedure, BUDS will tell you which wheel to do and for how long. It will then have you bleed the ABS unit. During this step of the procedure, BUDS will cycle the ABS unit on and off numerous times, getting all of the old fluid out and replaced with new clean fluid. I did a flush on a friends 2016 F3T today. The bleeder screw on the ABS unit has considerable corrosion and the fluid that came out is very cloudy, dirty, and contaminated with water. (Brake fluid absorbs water out of the air). Getting all this moisture out of the fluid will prevent corrosion in your calipers, brake lines, and ABS unit. Corroded calipers and/or ABS unit can prevent them from functioning properly, which means they might not apply properly or release properly causing dragging brakes.

20230325_150139.jpg 20230325_150207.jpg

[Cobwebs]

I always wondered how much the fluid gets circulated from one end of the system to the other between flushes. Does it just sit dormant or does it visit all areas. Would not using BUDS still eventually get all the fluid exchanged especially if you activate the ABS unit ocassionally. Never had corrosion problems so presumed I was doing it right.

[UtahPete]

I'd like to do the job properly but don't have access to BUDS. Is there anyone with the tools and knowledge to perform this within a days' ride of Salt Lake City?

[Jetfixer]

I always wondered how much the fluid gets circulated from one end of the system to the other between flushes. Does it just sit dormant or does it visit all areas. Would not using BUDS still eventually get all the fluid exchanged especially if you activate the ABS unit ocassionally. Never had corrosion problems so presumed I was doing it right.

First off, there is absolutely NO circulation of brake fluid. Ever. In ANY vehicle. (Except Airbus aircraft). When you press on the brake pedal, you push fluid from the reservoir to the calipers. Period. When you release the brake pedal, the pressurized fluid nearest the reservoir simply relaxes and returns to the reservoir. The fluid within the brake lines, calipers, and most importantly, the ABS unit simply gets pressurized, then depressurized. There is virtually no flow of fluid. Meanwhile, the fluid that is trapped in the calipers and ABS unit get repeatedly heated and cooled by your braking action. The hottest point being at the brake pads. This degrades the fluid over time. Add to this the inherent absorption of moisture in the fluid, and you can see the results in my photo above. As stated above, you need BUDS to activate the ABS unit to flush out the trapped fluid within it. Short of that, you are simply only flushing out the lines and calipers, which is absolutely worth doing, but don't think you are getting it all.

[Isopedella]

How about doing the flush in the normal way and ignore the ABS unit initially.
Then have a crazy mad few minutes putting the ABS through a repeated workout?

Like getting up to some speed (dont be stupid here - safe place - look behind you - up an down an empty lot coms to mind ) then hit the picks big time, enough to activate the ABS.

Then repeat over and over.
Then re-bled in the normal way.

I'm guessing fluid goes into the ABS unit from the master cylinder.......
Then comes out back into the system after activation.

I'm also guessing that Jetfixers bag is the total product from the whole system, some 7 years old as he says its from a 2016 but dosnt mention it been done since new.

Just throwing it out there.

[Ddub]

So those of us without BUDS can expect to pay how much for this service? And since you have BUDS and are close?

[Jetfixer]

How about doing the flush in the normal way and ignore the ABS unit initially.
Then have a crazy mad few minutes putting the ABS through a repeated workout?

Like getting up to some speed (dont be stupid here - safe place - look behind you - up an down an empty lot coms to mind ) then hit the picks big time, enough to activate the ABS.

Then repeat over and over.
Then re-bled in the normal way.

I'm guessing fluid goes into the ABS unit from the master cylinder.......
Then comes out back into the system after activation.

I'm also guessing that Jetfixers bag is the total product from the whole system, some 7 years old as he says its from a 2016 but dosnt mention it been done since new.

Just throwing it out there.

The quick answer is NO. Just as in the calipers, the fluid in the ABS unit is trapped, and is simply pressurized and depressurized by stomping on the brake pedal to activate the ABS module. There is NO flow of fluid. And yes, the photo shows the collected fluid from all of the bleeders. But I don't know if this particular bike was ever bled before. It was bought used, without knowing it's history. My point is, if you only bleed the calipers in the traditional method, you will NOT know the condition of the fluid in the ABS unit. Since the ABS unit is installed as an emergency device, I would not mess around with it. You use your brakes every time you ride. How often have you felt the ABS unit activate? This is the device that lurks in the background waiting to save your butt. If you take care of it, it will take care of you.

[Jetfixer]

So those of us without BUDS can expect to pay how much for this service? And since you have BUDS and are close?

I work on friends' bikes as a side hussle to my main job. Since I try to be fair, I tell my friends to find out what a dealer would charge for any given service and I'll do it for half. This person called a local dealer and was told it was a 5 hour job and would cost $700. I told her that was BS and I'd do it for $175. An independent motorcycle shop told her (without using BUDS) that it would be $175-200, plus $19.99 for DOT 4 fluid. Really? A quart of DOT 4 at Wally World is less than $8. And yes, I'm 1/2 hour south of you.

[Freddy]

One of these is a good thing to have. It eliminates guessing on moisture content. Just put the 2 probes in the fluid, not the whole tip of the pen as the plastic it's made of doesn't like brake fluid - 'go figure.'

https://www.ebay.com.au/itm/31370571...3ABFBMssS7ueNh

For those who can't get BUDS to do the flush, activating the ABS unit periodically is better than not doing it as, although it doesn't move any fluid as Jetfixer says, it does 'exercise' the tiny valves inside the ABS unit. This will help to keep them free. I repair early Kawasaki 1400GTR / C14 ABS units which are prone to moisture content failure (if not flushed/bled as often as recommended) due to there being no option in the dealer tool (KDS3) to do what BUDS can do on Spyders.

[Cobwebs]

First off, there is absolutely NO circulation of brake fluid. Ever. In ANY vehicle. (Except Airbus aircraft). When you press on the brake pedal, you push fluid from the reservoir to the calipers. Period. When you release the brake pedal, the pressurized fluid nearest the reservoir simply relaxes and returns to the reservoir. The fluid within the brake lines, calipers, and most importantly, the ABS unit simply gets pressurized, then depressurized. There is virtually no flow of fluid. Meanwhile, the fluid that is trapped in the calipers and ABS unit get repeatedly heated and cooled by your braking action. The hottest point being at the brake pads. This degrades the fluid over time. Add to this the inherent absorption of moisture in the fluid, and you can see the results in my photo above. As stated above, you need BUDS to activate the ABS unit to flush out the trapped fluid within it. Short of that, you are simply only flushing out the lines and calipers, which is absolutely worth doing, but don't think you are getting it all.

So any moisture is only in the reservoir because it doesn't circulate ?

[Freddy]

No. It can get in thru caliper piston seal and even thru rubber hoses.

[Peter Aawen]

So any moisture is only in the reservoir because it doesn't circulate ?

No. It can get in thru caliper piston seal and even thru rubber hoses.

And cos the rest of the 'un-tainted fluid' is more hygroscopic than the originally moisture tainted fluid which is now at least partially diluted, then as more moisture is absorbed from any source, the contamination will then be effectively passed from molecule to molecule until ALL your brake fluid is contaminated - and it doesn't need to move at all to do that!!

Brake fluid will effectively suck ANY moisture that it can from any source it gets access to; so every time you open the Reservoir, the surface of the fluid there sucks whatever moisture it can out of the atmosphere and keeps on doing that while-ever there's still any air remaining in contact with the exposed surface of the brake fluid; PLUS cos there's always a thin film of fluid left on the cylinder walls as they operate, it'll be sucking moisture in thru the piston seals & cylinder walls every time the brakes go on OR off; and as mentioned, there's also the brake fluid that slooowwly permeates thru any rubber/non-metallic sections of brake line, only as soon as the first brake fluid molecule makes it into contact with the air/atmosphere, the rate that moisture gets sucked back thru the rubbery stuff is massively accelerated!!

And once you've got any moisture in there, your brakes will no longer be working at their peak levels - which will gradually be getting worse and worse as you get more water in there!!

[Cobwebs]

And cos the rest of the 'un-tainted fluid' is more hygroscopic than the originally moisture tainted fluid which is now at least partially diluted, then as more moisture is absorbed from any source, the contamination will then be effectively passed from molecule to molecule until ALL your brake fluid is contaminated - and it doesn't need to move at all to do that!!

Brake fluid will effectively suck ANY moisture that it can from any source it gets access to; so every time you open the Reservoir, the surface of the fluid there sucks whatever moisture it can out of the atmosphere and keeps on doing that while-ever there's still any air remaining in contact with the exposed surface of the brake fluid; PLUS cos there's always a thin film of fluid left on the cylinder walls as they operate, it'll be sucking moisture in thru the piston seals & cylinder walls every time the brakes go on OR off; and as mentioned, there's also the brake fluid that slooowwly permeates thru any rubber/non-metallic sections of brake line, only as soon as the first brake fluid molecule makes it into contact with the air/atmosphere, the rate that moisture gets sucked back thru the rubbery stuff is massively accelerated!!

And once you've got any moisture in there, your brakes will no longer be working at their peak levels - which will gradually be getting worse and worse as you get more water in there!!

Ah ok, so the molecule to molecule contamination could that be used to advantage by just bleeding as usual if you don't have Buds and in effect drawing the contaminated fluid left in the ABS unit into the newly introduced fluid thus lowering the total percentage of water present? Not 100% uncontaminated but neither would be Buds flushed after say a month or so or doesn't it work like that?

[Peter Aawen]

Ah ok, so the molecule to molecule contamination could that be used to advantage by just bleeding as usual if you don't have Buds and in effect drawing the contaminated fluid left in the ABS unit into the newly introduced fluid thus lowering the total percentage of water present? Not 100% uncontaminated but neither would be Buds flushed after say a month or so or doesn't it work like that?

You're right about the 'Not 100% uncontaminated' bit, and while it does lower the overall total percentage of water present in your contaminated brake fluid, there's really no 'used to advantage' bit to it at all, cos once it's contaminated at all, it only gets worse from there... It's sorta like adding a dash of petrol to wine or to your beer; if it's a tiny amount, you might not spit it out immediately... but if you then start gradually adding more petrol in the hope of making it taste/become safer, it really doesn't cos just like your Spyder's brake fluid is contaminated with any moisture in it & so degraded somewhat/not working quite as well as it should, once the wine or beer becomes contaminated with any petrol, then even if you don't spit it out immediately it's STILL unsafe and basically no good from there on in! Make Sense??

And Please, don't anyone try that, it really ISN'T safe, it's just an example of how once something that was once drinkable/useable gets contaminated, it becomes bad; and from there on in, no matter how much more contaminant you might add, it only gets worse!!

[Freddy]

Like the man says:

Ryde More, Worry Less!

[BLUEKNIGHT911]

The factory recommended interval for brake fluid flushing is every 2 years. Yes, of course you can bleed the brakes the old fashioned way, one wheel at a time. However, there is no way to bleed the ABS unit without hooking up to BUDS/BUDS2. During the procedure, BUDS will tell you which wheel to do and for how long. It will then have you bleed the ABS unit. During this step of the procedure, BUDS will cycle the ABS unit on and off numerous times, getting all of the old fluid out and replaced with new clean fluid. I did a flush on a friends 2016 F3T today. The bleeder screw on the ABS unit has considerable corrosion and the fluid that came out is very cloudy, dirty, and contaminated with water. (Brake fluid absorbs water out of the air). Getting all this moisture out of the fluid will prevent corrosion in your calipers, brake lines, and ABS unit. Corroded calipers and/or ABS unit can prevent them from functioning properly, which means they might not apply properly or release properly causing dragging brakes.

20230325_150139.jpg 20230325_150207.jpg

I've thru to post #15, and learned a lot .... Thanks ..... That bag has all the fluid from the Spyder. Does anyone know how much fluid is in the .... ABS unit ????? .... thanks ..... Mike

[FrogmanDave]

I've thru to post #15, and learned a lot .... Thanks ..... That bag has all the fluid from the Spyder. Does anyone know how much fluid is in the .... ABS unit ????? .... thanks ..... Mike

I was wondering the same thing. I have read here it is a miniscule amount.

[UtahPete]

According to the 4 ads I checked NONE of them will send it to the USA ..... however if you go to e-bay in the U.S. they sell for as low as $2.00 shipped free ..... I think I'll get one ..... Mike

https://www.amazon.com/brake-fluid-t...e+fluid+tester

[Isopedella]

Many ways to check the fluid.
You can also use a Digital Multi meter.
The procedure.

Set it to volts.
Insert your positive meter probe into the brake fluid while avoiding contact with the reservoir itself. Negative to an earth.

Any reading over 0.30 volts is too much.

----------------------------------------------------------------------
You could check your coolant while your there with the multi meter.

Start her up. When the engine reaches operating temperature, insert the positive probe directly into the coolant.

Rev the engine to 2,000 rpm and place the negative probe on the negative battery terminal.

If the digital meter reads . 4 volts or less, your coolant is in good condition.

[Knizar]

Why is it that the Spyder and other MC's are recommending this complete brake fluid change every 2 years, when our other POV's (cars, pick-ups, & such) have made NO major mention about having this done periodically? Even after more discussion on this, how many of us will actually put-out money to the dealers to get this job half/ass done. I would Gladly ride my trike to South Carolina and have Jetfixer do it before I would trust my local dealership to complete this task! "they won't let me watch them" Food for thought, another .02 cent opinion! Bill

[Isopedella]

Possibly a CYA approach based on worst case scenario I would guess.

Any problems - well you were informed.

[Knizar]

Possibly a CYA approach based on worst case scenario I would guess.

Any problems - well you were informed.

True, I agree, kind of like the side effects on a pill bottle. After reading the side effects that you could get makes a person second guess whether or not you want to take the pill!

[kj2364]

Just for another point of view, in 50 years of cars, trucks, motorcycles, snowmobiles, 4 wheelers, you name it, I have never changed brake fluid in anything and probably never will. Have many vehicles and toys from new to 30+ years old with 100K+ miles. Never had a brake problem with anything.(other than shoes/pads of course) Not saying it isn't a good idea to do it, just that's it's never been a problem for me.

[DaniBoy]

I just flushed mine. First, I removed the OEM bleeders and replaced them with Speed Bleeders on just the three wheels, and left the VSS alone. It holds such little fluid that it really can be ignored if you’re going to flush every two years. As per BajaRon, the fluid is NOT static. What little is left in the VSS will eventually mix with the rest of the system. Also, he said that if done properly, i.e. NO trapped air, that the VSS can indeed be bled without BUDS. I don’t have access to BUDS, so I’m just going to leave my VSS be. With only a Tablespoon or so, combined with a biannual flush, it shouldn’t make a difference that I can see.

[Knizar]

I'm all for getting the brake fluid tested, and then pursue the recommendations of the handbook.