Brake Fluid

[Chef Eric]

Good morning! I have 2002 R1150RT and my brake failure warning light and general caution is flashing. I have brakes but I have been told I need to fill my brake fluid. I have checked the remote resivoir. How do I top off the rear master cylinder or do I need to take it in to get serviced? Does this require a full brake system bleed?

 

Thanks!

[dirtrider]

Good Morning Chef

 

With both the ABS and General light flashing and the brakes working that does sort of point to low fluid levels in the ABS controller reservoirs.

 

To access those reservoirs you first need to remove the plastic Tupperware, then remove the gas tank, that then will allow access to the ABS controller. Once you get to the ABS controller there are a couple of caps on the top that you remove to check the internal fluid levels. Your flashing light issue isn’t caused by low fluid in the external reservoirs by the front lever or rear pedal it is relating to the fluid level in the ABS master cylinders under the gas tank.

 

If your brake pads are worn out that can lower the fluid level in the end that has the worn pads. SO, if you have very worn brake pads on one end or the other then installing new brake pads on that end can sometimes put the flashing warning light out as that forces some of the caliper fluid to get pushed back into the ABS controller reservoir.

 

There is one other way, (IF) you study the system and FULLY understand how it works. With enough knowledge on how the system functions, what end is causing the problem, and how the integral reservoirs interrelate to the brake system you can force some brake fluid back up into the integral reservoirs back in through the caliper bleed fittings. This is not something to try unless very knowledgeable on your ABS system. This way MUST be done without introducing any air into the brake system.

 

[Chef Eric]

Thanks for the feedback.

[ElevenFifty]

The correct procedure would be to replace the pads as needed, then to perform a brake system bleed ... it is not that hard and there are is a good pictorial guide in the FAQ section. You'll need a couple of special tools ...

 

1 - a funnel with a screw in stopper in place (for adding fluid to the ABS controller),

2 - a turkey baster or better, one of those large turkey injector syringes with a couple of inches of tubing attached (for removing fluid from the lever reservoirs

3 - some tubing that fits over the brake bleed nipples and runs to a container of brake fluid (to prevent air from being sucked into the system while you pump out the old fluid)

 

One of the great things about the ABS system is that (once you have a funnel full of fluid screwed into the fill opening, and the flow-back reservoir connected to the nipple) the brake circuits are dead easy to bleed. You just turn on turn on the key and tap the brakes ... the system will pump out all the old stuff while it sucks in the new fluid. Keep clean fluid in the funnel as the bike drinks it ... eventually the old yellow-brown fluid will be evacuated and the clean stuff will start to flow.

 

The controller circuits are a bit more complicated to do because the clearances for tools sucks and you have to bleed in a specific order, but all that is covered in Leslies slide show.

 

It really isn't that difficult and can save you a ton of cash.

[Goomicoo]

I just looked at my controller on the '96RT. It's not the same as the one in Leslie's slide show. It only has 2 bleed screws. I'm going to have to rush order a book although I kind of like taking things apart blindly. Putting them back together is another matter however.

[dirtrider]

Afternoon Goomicoo

 

Your 1100 has the ABS-2 brakes not the I-ABS system that is on the 1150. Your unit doesn’t have the apply and control sides, just a straight through system.

 

You can bleed your ABS-2 system at the caliper fittings just like a conventional brake system, then you can just go back and bleed at those two ABS controller fittings if you want to. Most people don’t bleed the ABS fitting on the 1100 bikes but on a bike that has been sitting like yours has probably not a bad idea to bleed there.

 

[NonComp]

I recommend bleeding at the ABS II controller at least once. I found a lot of black gunk and air in my '96 1100 when I bought it. The ABS II units are easy to bleed, but expensive to replace.

[ltljohn]

Chef Eric,

You should change the fluid in your system. It is not hard to do once you know how. Update your profile a bit, there may be someone close to you willing to assist. You may want to attend a tech day in your area.

[Goomicoo]

Afternoon Goomicoo

 

Your 1100 has the ABS-2 brakes not the I-ABS system that is on the 1150. Your unit doesn’t have the apply and control sides, just a straight through system.

 

You can bleed your ABS-2 system at the caliper fittings just like a conventional brake system, then you can just go back and bleed at those two ABS controller fittings if you want to. Most people don’t bleed the ABS fitting on the 1100 bikes but on a bike that has been sitting like yours has probably not a bad idea to bleed there.

What would be the proper procedure? Thanks

[philbytx]

I bleed both ABS II and iABS systems, for my R1100R and my R1150RT.

 

On ABSII.

This still requires taking off the tupperware and getting the tank out of the way. After you get it nekkid :

Remove the top off the handlebar brake reservoir, drain fluid (Turkey baster or clean tubing) and refill with fresh fluid.

Note: You will need a bleed screw for the "blind" fitting on the RH front brake caliper. I use a SpeedBleeder SB1010S, which is the same bleed screw for my R1150RT clutch circuit. If you go to SpeedBleeders to buy, get yourself the catch bag & tubing while you are at it, makes life a lot easier

Ok, when you pull the front brake lever to bleed, make sure to cover your brake reservoir as it will spurt back. I use a folded up shop towel.

Bleed from LH front, then RH front (blanked off, use the SB1010S), then ABSII controller. And check the fluid quantity in reservoir to make sure you don't go too low!!!

Rear brake is the same procedure but with only one bleeder at the rear caliper.

 

 

[Goomicoo]

So I bleed the ABSII controller the same way as I would a caliper?

[dirtrider]

Morning Goomicoo

 

Yes, but do it last as that way only a very little amount of old fluid will be in the top of the ABS controller. One ABS fitting is front brake circuit and one ABS fitting is rear brake circuit so you will have to pump the appropriate end.

 

[Goomicoo]

Will do. Thanks