Bleeding Brakes Inc ABS systems.

S1000RR  FORUM

Help Support S1000RR FORUM:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

HongKongPhooey

Well-known member
Joined
Jul 6, 2011
Messages
95
Reaction score
0
Location
Douglas Isle of Man
Hi All, this is a brief how to - Bleed an ABS Front and Rear Brake System.

I must add, I'm not a pro mechanic but this worked for me, so I will share my experience. I will also add, there are many different speed bleeder systems available to buy, though I don't really get on with them, so this is done the old school way.

You will need, a clear glass jar ( I use a clean DRY de-labeled coffee jar ) filled with 1/4 to 1/3 of old brake fluid.

A clear length of plastic tube ( the inside diameter needs to make a snug air tight fit over the bleed nipple. ) about 18 inches long, it needs to be long enough to run from the nipple to the jar without kinking, but not so long you spend ages getting fluid through it. It needs to be clear, so that you can see fluid flowing through it, eventually bubble-less. More about that later.

A small posi-drive screw driver.

A std Torx screw driver ( the same size as all the fairing fasteners. )

A 12mm, 11mm and 8mm spanners.

Old rags and a cable tie x2.

Firstly, undo the rear brake reservoir torx, pass under the sub frame rail and temporarily cable tie to the outside of the frame rail. ( its much easier to get access to the pot and top up this way. )

Now start on the fronts! Undo the reservoir cap using posi-drive screw driver. Lift out the rubber diaphragm and wipe with a clean dry cloth. Put some rags around the reservoir in case of any spillages.

Place the clear tube over the front right caliper nipple. Ensure the other end of the tube sits UNDER the surface of the fluid in the glass jar. Hold the bleed screw solid in the caliper with the 12mm spanner and crack the nipple open with the 8mm spanner. 1/2 to 3/4 of a turn is sufficient.

Now the technique.

Ensure there is always plenty of fluid in the reservoir, if not you will pull air through the system from the top and have to start again. You will probably only ever do this once :)

I use Motul RBF600. Just check what BMW recommends.

Holding the 8mm spanner so its very lightly closed the nipple, open about 1/2 a turn and pull the brake lever back to the bar fully. BEFORE you release the brake lever, very lightly nip the bleed nipple back up. Ensure the end of the tube doesn't come out of the old fluid as you're turning the tube back and forth.

Repeat this process, undo 1/2 a turn, then pull the lever back to the bar, lightly lock off the nipple THEN release the rake lever. The astute amongst you will by now have noticed that every time you release the lever, the brake fluid in the reservoir drops a little but as it refills the master cylinder. I'd guess you have about 10-12 pulls to empty a full reservoir.

I had a virtually dry set of lines and ABS pump and it took about 6 reservoirs to fill the first line from Lever/Master Cylinder down to the calliper.

As you see fluid start to flow through the clear tube, you will see its full of little bubbles, keep pumping and eventually they will become less and less. Remember though to keep topping up the reservoir :). When you can see its virtually free of bubbles, nip the nipple up properly this time.

Now repeat the process for the Left calliper. This side should be quicker as there will be lots of fluid in the line now already before it splits at the T-Piece under the bottom yoke.

Once the front two callipers are are initially bled up, you should now have a reasonable amount of pressure at the lever when both nipples are nipped down.

Now do the same for the rear, as far as I can tell, even on the ABS models, the two circuits do not mix (fluid wise) inside the ABS pump. This makes the rear, much faster and easier to bleed up than the fronts. The only difference to the fronts is the locking nut is an 11mm spanner to hold the bleed screw solid whilst cracking the 8mm bleed nipple.

Once all three callipers are bled, go around and do them all again and pump 5-6 more times per calliper once the clear tube has been filled. Nip everything up to the correct torques, wipe any fluid off or even better, a blast with brake cleaner and re-install the reservoir caps and the rear reservoir back inside the sub-frame rail.

Lastly, put a cable tie around the front brake lever and bar and pull tight. Leave over night. This will help if you have any stubborn trapped air anywhere and send it upwards to the reservoir.

Check the next day and hopefully everything everything should be nice and solid at the levers. If not, repeat until solid.

Hope this helps, I thought bleeding up an ABS system on the S1000 would be a bit of a nightmare, turns out, it wasn't any worse than any other non-abs systems I've bled in the past.

If you're really not sure, your friendly BMW dealer will charge you £90 for the pleasure. Well, at least mine would.

All the best.

Phooey.
 
Thanks.

I think I understood and can picture most of that.

What happens if you dont have any old brake fluid to put in the bottle at the start?

Do you start putting the new fluid into the reservoir before it is completely empty of old fluid?
 
Thanks.

I think I understood and can picture most of that.

What happens if you dont have any old brake fluid to put in the bottle at the start?

Do you start putting the new fluid into the reservoir before it is completely empty of old fluid?

Wouldn't have thought you would need fluid in the jar at the beginning anyway as the tube will full of air to start with, just make sure you tighten the nipple BEFORE releasing the lever. If you don't put new fluid in before the reservoir runs out then you will just suck a whole load of air back into the system and have to start from scratch. :)
 
Last edited:
I wouldn't worry too much if you don't have any old fluid, as you soon will have once you've started. The fluid in the jar acts like block to air flowing back up the pipe. It also allows you to see if any air bubbles are coming through. You will feel the difference between an empty and filled jar once you get going.

If you have a full system, then there will inevitably be a little mixing of the old and the new fluid. However, its a little like changing engine or fork oil, as long as you change the vast majority, you'll be fine.

Just pump the lever until the reservoir is low, but NOT empty! Then top up with fresh and repeat several times per caliper.
 
I wouldn't worry too much if you don't have any old fluid, as you soon will have once you've started. The fluid in the jar acts like block to air flowing back up the pipe. It also allows you to see if any air bubbles are coming through. You will feel the difference between an empty and filled jar once you get going.

If you have a full system, then there will inevitably be a little mixing of the old and the new fluid. However, its a little like changing engine or fork oil, as long as you change the vast majority, you'll be fine.

Just pump the lever until the reservoir is low, but NOT empty! Then top up with fresh and repeat several times per caliper.

Thanks, another question, is it possible to see the difference between the old and new brake oil, like it is with fork and engine oil?
 
I'd say not, though brake fluid is very hydroscopic and if there is any water in there (very unlikely) you'll see that. Old fluid that is open to the air (in your jar :)) goes a lot darker than new sealed fluid, but even then, its almost impossible to see the difference as its being pumped.

I used a full 500ml bottle of RBF600, but that was into a dry ABS system, I'd guess half that would almost entirely change the fluid in your lines.

HTH.
 
and rear...
You have to take them out to fill with fluid, cant see why you should need them?

Those diaphragms are there to keep the fluid settled in the reservoir, otherwise when the bike is being thrown about in turns, braking and acceleration its possible for air to get into the system.
 
Not sure how vital they are. I have fitted a Brembo reservoir and that doesn't have a diaphragm in.
 
Back
Top