Bleeding ABS bikes

[Coyote Chris]

For some reason, I have never considered trying to run the ABS pumps on my bikes when changing brake fluid. Modern bikes of some makes allow you to run the front and rear pumps using an app and a blue tooth to obdii cable. The FJR has a meathod where you put the bike in gear, side stand DOWN, put in a jumper in a plug, turn the bike on and press the now disabled starter button for four seconds. The vehicle computer now goes through a routine where it runs the front pump, the rear, and then the front pump again.
I have never even had the ABS come on with any of my bikes. Some people just find a wet surface and try to lock up the front and rear brakes to get the pumps working.
Not sure what the proceedure is on the XT and VFR.

I am wondering how many people do this on their own here or just blow off the ABS.

 

[ST1100Y]

I just draw lots of fluid though the system while replacing, to ensure flushing the modulator as well...

Which apparently hadn't been done during the previous ownership of ze GF's NT700VA, as my vacuum brake bleeder drew quite an amount of "banana milk" out there during my first service on it...

 

[Frosty]

If the ABS pump module is not activated, does that mean the fluid in the module never circulates How old could it be? Absorbed water in brake fluid causes corrosion. Hence recommendation for replacement every two years.
Just did two ABS bikes (VFR no ABS). On the BMWF800GT I used the GS911 device with a laptop. On the Triumph 900GT I used a Blue tooth device connected to the OBD connector and an Android Tablet with Tune ECU software. In both cases, I cycled the ABS pump and then flushed the brakes with new fluid. Then I ran the ABS pumps again with the apps to put clean fluid in the pumps. Finally I used the rest of the 1 Qt DOT 4 fluid to bleed and fill the brakes.

 

[Coyote Chris]

I just draw lots of fluid though the system while replacing, to ensure flushing the modulator as well...

Which apparently hadn't been done during the previous ownership of ze GF's NT700VA, as my vacuum brake bleeder drew quite an amount of "banana milk" out there during my first service on it...

An interesting idea. I think I need to see a schematic of a VFR brake system. When I do a fluid change, I use speed bleeders and pump lots of fluid though the various passages.
According to the web, ST1100Y is correct and Frosty is wrong in the case of my VFR. YOU ONLY NEED TO ACTIVATE THE ABS MODULATOR IF IT HAS AIR IN IT.



No, you do not need to activate the ABS modulator to perform a routine brake system flush on a 2014 Honda VFR (8th Generation VFR800F/FD). [1, 2]
The system can be bled and flushed normally using traditional manual methods, vacuum bleeding, or pressure bleeding. Fluid passes freely through the open valves inside the modulator during normal maintenance. [1, 2, 3]
However, the rules change depending on your specific situation:

1. Routine Maintenance & Fluid Flushes
If you are just changing out old brake fluid with fresh DOT 4 fluid, you can proceed with a standard bleed. You only need to open the reservoir, clear out the old fluid, and pump fresh fluid down to the caliper bleed nipples until it runs clear. [1, 2, 3]

2. When Modulator Activation IS Required
You only need a specialized scan tool or jumper wire sequence to electronically cycle the ABS solenoids if:

• Air has gotten trapped directly inside the ABS module.
• You have replaced the ABS modulator unit itself.
• The brake master cylinder ran completely dry during a flush, introducing large quantities of air upstream. [1, 2, 3]

A Note on the 2014 VFR Braking System
Unlike previous generations (such as the 6th-gen VFR800 VTEC), the 2014 8th-generation VFR800 dropped the complex Linked Braking System (LBS). It uses a conventional, unlinked setup where the front lever controls only the front brakes, and the rear pedal controls only the rear brakes. This makes flushing the system straightforward and identical to any standard, non-linked ABS motorcycle. [1, 2]