If the ABS fails you still have your brakes. A Dealer mech told me they dont bleed the ABS, just the system as normal , he said, "there is such a small amount of liquid in the system it will change out on its own if the ABS activates " his words. Tune ecu will open and close the modulator with the Android version ( please check it may be the windows version, I muddle them up). If the fluid in the modulator is locked in the centre of the system then just as you cant bleed it air or water cant enter it.
......which is why I do my own maintenance. See my earlier post #17 if you're thinking of doing it yourself (properly).
There's no issues to bleed ABS brakes. The procedure is described in workshop manual. First you bleed right caliper. Then left. Then master cylinder. Then you bleed ABS modulator via Bluetooth and TuneECU for Android. Then again right caliper -> left caliper -> master cylinder. That's all. Made it with my 675 Daytona ABS this winter.
Exactly Eldon, my thoughts exactly. Bled ABS system today with DealerTool. Was surprised it only activated the system for about 10sec at a time. This correct? Only reason I ask is details mention it’ll max 90sec. Also anyone know the capacity of the brake system?
Generally speaking, it's not the abs module that can be damaged, it's the pump motor due to overheating. I know that on automobile abs systems if you open the bleeder valve (key on) wile on the brakes, the abs pump will activate pumping the fluid out. (abs pump/value bodies have a pressure sensor built in) We would remove all the old fluid from the brake reservoir, add fresh fluid then wile bleeding just keep the reservoir topped up till you close off the bleeder valve. We would keep the activation time under a minute per caliper, then let the abs pump rest for a minute & repeat till all calipers were bled. I would think 15 to 20 seconds per caliper would be more than enough time to get a good and complete flush on a bike's abs system. Also it might be easier with help from a friend, due to the small brake fluid resie's bikes have.
That seems a strange order unless using a reverse bleed process. I would have bled the master cylinder first in order to create the push then nearest to furthest caliper.
So just to clarify... Can the system be bled without the tuneecu tool to open/close the ABS module? I have a 2016 so whilst i think its now supported by tuneecu via bluetooth, not all functionality is available...plus i dont have any of the kit yet. I'm happy with bleeding the brakes then pumping the ABS on the road followed by another bleed, but not sure if this is possible at all without opening up the ABS module first? Ta
So just to clarify... Can the system be bled without the tuneecu tool to open/close the ABS module? I have a 2016 so whilst i think its now supported by tuneecu via bluetooth, not all functionality is available...plus i dont have any of the kit yet. I'm happy with bleeding the brakes then pumping the ABS on the road followed by another bleed, but not sure if this is possible at all without opening up the ABS module first? Ta
You can bleed normally. You will have a small amount of old fluid in the system ( dont worry about it) In fact I have just bleed mine with no electronic tools this afternoon. Just a spanner and a tube.
I never understand how a completely sealed brake system can become "contaminated by water". The only route in would be via the reservoir, which has a flexible seal. I think a lot of it is dealer BS as usual. I had this with a new Fiesta I bought and the dealer said the brake fluid needed to be changed after 2 years. I asked him how it had managed to become unsafe or unusable after 2 years and he didn't know.
Because brake fluid is hygroscopic and absorbs water however i agree i have never seen any brake system contaminated with water ....but i have seen the results of old brake systems that have been left for years and found pistons very rusty presumably from water contamination.
got to help brother-in-law fit some braided hoses and do a brake service on his Harley next week. Stopping is pitiful, but I guess he doesn't go that fast.
The caps on the fluid reservoirs do have a small vent hole in them. This allows free movement of the fluid, other wise pressure could build in the reservoir and start putting pressure on the caliper pistons. The caps do have a seal on them to keep fluid from leaking out, but it dose let ambient air in. The other way moisture can enter the system is through the caliper piston seals. Seals are never 100%. 99.9, but not 100% the seals and pistons will develop micro scratches which allow the moisture in. As stated above, brake fluid is hygroscopic, water will get in. There's probably more ways too, but these are the ones that come to mind.
The hole in the fluid reservoir cap is to allow the rubber bellows to move with the fluid which is to all intents and purposes is sealed and should be air tight.
