r1100rt brake bleed sequence question

[TracyPrier]

Hi guys

 

About to do a brake fluid flush on the 2000 1100rt.

 

I see that there are 2 bleed nipples on top of the ABS unit.

 

Am I right in thinking they are to bleed the circuit from the resevoirs to the ABS?

 

And what sequence do I bleed in?

 

Thanks all and God Bless

Tracy

[Mudman]

Tracy,

Do yourself a huge favor and do not loosen those bleed screws on your ABS. They are mounted in a fixture that uses a blind nut inside of the module. If you encounter a very tight bleed screw you stand a chance of loosening the underlying nut. Bad MOJO. You may be unable to get it retightened and now you have a leaking ABS module.

 

The standard procedure is the bleed your brakes in a conventional manner ignoring the ABS bleed screws. The manual and service bulletins want you to retract the pistons of the front calipers to get a good flush and then remove the rear caliper and after retracting the pistons with a spreader tool bleed it with the brembo sign facing up. This releases air bubbles that can be trapped in the mounted position. This is the best method.

 

If you don't have the tools you can try just bleeding the calipers as they are mounted, but if you end up with a soft pedal or lever you will likely need to do the full procedure described.

 

Having fun yet?

[John Dickens]

The BMW service manual makes no mention of bleeding the ABS unit but there are members of this board that recommend doing so.

Retracting the pads will push almost all of the old fluid out of the calipers ensuring a more complete change of fluid. I tend to change pads at about the half worn point so I tend not to bother with this step as the pistons are not far out anyway.

 

As for the order of bleeding I have always bled the longest line first so my order would be:-

 

Front nearside

Front offside

 

The rear system is independent of the front so you can bleed it first or last. It doesn't matter

[Joe Frickin' Friday]

Tracy,

Do yourself a huge favor and do not loosen those bleed screws on your ABS. They are mounted in a fixture that uses a blind nut inside of the module. If you encounter a very tight bleed screw you stand a chance of loosening the underlying nut. Bad MOJO. You may be unable to get it retightened and now you have a leaking ABS module.

 

Wow, that's news. My understanding was that on a newish bike, if the brakes still felt spongy after a traditional bleed, there might still be air present at the ABS unit, which could be removed by bleeding at the ABS bleed fittings.

 

Bleeding at the ABS module bleed fittings is also an issue if air is somehow introduced into the system, either through a screwed up bleed job, or through replacement of the lines. But if you're confident there's no air in the system, then there's no need to bleed anywhere but at the calipers.

 

NOTE TO NEWBIES: this applies only to bikes WITHOUT the servo-assisted brakes. If you've got servo-assist, click here and here to see how to bleed your brakes.

[smiller]

Do yourself a huge favor and do not loosen those bleed screws on your ABS. They are mounted in a fixture that uses a blind nut inside of the module.

News to me too! How certain of you of the above info? May I ask the source?

[Mudman]

This is straight from BMWNA training. Nothing in the repair manual suggests using these points when bleeding the brakes. They there primarily for new module installation. While I agree it may be necessary to use these bleed points, they should be avoided if possible for the stated reasons. The chamber they bleed from is very small when the ABS is inactive henceforth they are usually not needed. If you have spongy brakes I would be sure you thoroughly bleed the system and tapped the calipers with a soft plastic handle (screwdriver)to loosen clinging air bubbles. I have done many bikes and not had to bleed from the ABS II module unless the module was replaced.

 

Bottom line: it is not prudent to take a chance of ABS II module damage from using it's bleeding screws if the bleed job can be accomplished using the bleed points at the calipers. This follows factory procedures.

[Ken H.]

The BMW service manual makes no mention of bleeding the ABS unit but there are members of this board that recommend doing so.

I can't speak for every member of course, but for the R1100 series non-EVO brakes, many of us ignore the bleeders on the ABS unit. The 1150 series is a different matter where there are six bleeders on the ABS unit that must be bleed in a specific order.

[TracyPrier]

Hey thanks Mudman and others

 

Great news I'll stick to the simple method (which always suits me )

 

The pads are all new so I'll just bleed with calipers in-situ and go from there if there is any spongyness.

 

Last question: will 500mls of DOT4 be enough or do I buy 1 litre??

 

Thanks

Tracy

[Mudman]

500ml should be more than enough.

 

Have fun and keep the water spray bottle handy in case you spill