'96 R1100: Replaced Rear Brake MC... Bleed ABS?

[tvpierce]

Good morning.

 

I just replaced the rear master cylinder on my '96 R1100RT.

 

Do I need to first bleed at the ABS unit under the tank, or can I just bleed at the rear wheel?

 

Thanks in advance.

 

[szurszewski]

You can probably get away with bleeding from the rear wheel depending on how much air you let in. If you do have to bleed at the abs block, you can do it without removing the tank.

[AndyS]

Don't you mean the that you changed the 'slave' cylinder?

[tvpierce]

I pumped the reservoir dry with the master cylinder so it wouldn't leak when I removed the brake line. In hindsight, that was not such a great idea.

 

So there is a lot of air in the line now.

 

How do I access the ABS block without removing the tank?

 

Again, thanks in advance.

[Michaelr11]

The rear ABS circuit is a pain because the ABS module is the highest point in the circuit. Makes it very hard to get fluid to move thru once you have air in there.

 

The easiest way to get this fixed - go to a farm supply place and buy an animal syringe. Attach some tubing to the bottom of the syringe and attach the tubing to the bleeder at the rear caliper. Fill the syringe with brake fluid and open the bleeder and the reservoir. Push the plunger of the syringe and force the brake fluid up the circuit. It will fill the lines and the ABS and will fill the reservoir. Reading this explanation takes longer than the process. It works!

[tvpierce]

Does the reverse bleeding procedure negate the need for bleeding at the ABS block?

 

 

[Michaelr11]

Yes. Some will say no, but the R1100 ABS2 system is a complete fluid run from caliper to the reservoir. It's possible that a little old fluid might hide in a crevice but my experience has been that when the fluid is kept fresh, then whenever I have cracked open the bleeder at the ABS the fluid there was also clear and fresh.

[szurszewski]

I pumped the reservoir dry with the master cylinder so it wouldn't leak when I removed the brake line. In hindsight, that was not such a great idea.

 

So there is a lot of air in the line now.

 

How do I access the ABS block without removing the tank?

 

Again, thanks in advance.

 

You need to remove left and right sides of the main Tupperware, and then you can lift the rear of the tank enough to get to the ABS block. I used a chunk of 2x4 to hold the tank up.

 

 

[tvpierce]

OK. I have the tupperware off already for other service. Will try the reverse bleed, and bleed at the ABS unit.

 

Thanks!