2006 BMW R1200RT Brake and ABS Bleed

[RoyB]

Greetings all

I recently replaced the transmission on my 2006 BMW R1200RT which has 68,000 miles.  In order to replace the transmission, the frame had to be split requiring the removal of one of the lines from the ABS Controller to the rear brake. There is now air in the system that I need to remove prior to getting the brakes to work again.
I purchased a GS911 in order to assist me in the bleeding process, but find that the Whizzy Brakes on this model may or may not require the use of the GS911.  My question is as follows:

I need to get the air out of the rear line from the ABS to the rear caliper.
How do I bleed the line if the ABS cannot be powered up?  Is this a simple matter of bleeding the caliper and refreshing the brake fluid level in the ABS Reservoir or is there more to this? 
Thanks

 

[mike d]

Just had a look on the Function Chart for your R1200:

https://www.hexcode.co.za/products/gs-911/procedures/iabs2can

Mike

[RoyB]

Thanks Mike.  The link you provided outlines the ABS 2 found in 2007 and later bikes, not my 2006.

iabs2can

Found in models:
The 2nd generation integral ABS, first introduced in Q4 of 2007. This generation, unlike the first is not servo assisted, and is found on most R1200 (K2x) and most K1200 and K1300 (K4x) models.

[mike d]

Sorry, got my systems mixed up:

Function chart for iABS (as on your bike)

https://www.hexcode.co.za/products/gs-911/function_charts/iabs_can_func_chart

And how to bleed them:

http://users.rcn.com/dehager/service/service_abs3.pdf

Mike

[RoyB]

Thanks Mike
In looking at the document, everything looks good until Page 8, item number 20 where the instructions outline turning on the Key to allow the ABS to initialize.  I will go through the bleeding process to see if this happens after removing the air from the rear brake.  I have a MityVac as well as a bleeding solution that uses an air compressor to create a vacuum to pull the fluid from the lines. 

[Jughead]

Why is it that the ABS cannot be powered up?  You unfortunately do need to power it up to bleed it correctly, as the valves need to be activated to clear the air.

What I normally do is re-assemble the bike to a point where I am about to put the tank back on. i.e. all electrical plugs/sockets have been re-connected and the battery has been re-installed and connected. 

Power up, bleed the brakes, power off and complete the re-assembly.

[RoyB]

I believe I have sorted this out with help from those in the know.  The ABS will not activate if there is air in any of the lines, so the air mist be bled out the lines manually.  I started with my Mity-Vac and gave up on that idea.  Instead I did the typical pump and bleed by opening each of the valves in the proper sequence as outlined in the document called BMW Integral ABS Systems Flushing and Bleeding 101.  By following the process multiple times as suggested, I was able to get the ABS to activate.  Once activated, I rolled the bike off of the lift and tried the brakes with the ignition on.  The ABS activated as hoped.  I have other loose ends to tie up prior to reassembly but the bike should be back on the road in the next week or so.
Thanks to everyone who provided feedback.  I hope this helps anyone else who finds themselves in this situation.

[Jughead]

I believe I have sorted this out with help from those in the know.  The ABS will not activate if there is air in any of the lines, so the air mist be bled out the lines manually.

That statement is a little misleading.  The ABS WILL activate if there is air in the system.  In fact, it will even activate without any of the brake lines connected to the pump.

It will, however, not activate if the pump senses a low fluid status.  There are 2 floats under the black cap on the pump that activate the "Level Low" switch.  Just topping up the fluid levels would have resolved the issue.

[RoyB]

Good point worth noting.  There seems to be a great deal of little known facts and details regarding this system. 

[Desmondtully]

Can someone who has a functioning ABS bike help me out with a couple of things?

I am looking for pictures of the front brake MC switch and the pigtail that goes to the harness. I'd like to see what the connectors on both sides look like and what their pinout is.