Bought another GS last week knowing the iABS/Serv assist pump was failed. New pumps are $3,000 and these are not rebuildable...well they are but its around $1,500 - $2,000 with shipping and insurance to and from Europe and about 8 weeks to have the repair. So the servo-ectomy it is. Sure it abandons the ABS but these bikes actually ABS was an option. There were available w/o so I'm just going back to its roots.
3/16" brake line - about $0.03 worth
Bubble flare tool - $19 at HF
2 hours and 2 minutes of your time
Remove the tank and expose the servo pump. pull the hairpin clips so you can pull the rigid brake lines
Pull the filter screen out of the pump
Suck out all the brake fluid you can
Undo the upper bake line fitting at the jumper on the right side of the head stock
Old rigid brake lines removed and new jumper (I had the jumper already made.)
Install the jumper in the crossover fitting and snug. Front circuit is now bypasses
A piece of tape over the opening where the old rigid brake line was
Put the old rubber boot back over the tape to seal off the pump
Undo the hairpin clip for the rear circuit
Undo the rigid brake line at the rear master cylinder and remove the old rigid brakes line. You will have to cut the one in the middle to get it out.
Now onto the rear jumper. Since BMW uses a special fitting here, we need to harvest one end of an old brake line and then bubble flare the other to make a jumper/adapter
Rear jumper bubble flared and ready for final tweaking/fitting to get it just right
Rear jumper installed
Bleed the rear caliper and 2 hours and 2 minutes later you're all done and have excellent non-ABS brakes
Some people remove the ABS pump as it does lighten the bike by about 7 pounds but if you do this you will have to remove the "brain box" on the right side and then make a waterproof cover and mounting bracket. If you do not reuse the brain, you will lose brake lights and speedo function. Haining gone through the trouble of removing the ABS pump, making a cover plate and mount its it far easier to abandon the ABS pump in place. Then it is sealed and sturdily mounted, and you retain brake light and speedo functions.
Cheers,
P-14
3/16" brake line - about $0.03 worth
Bubble flare tool - $19 at HF
2 hours and 2 minutes of your time
Remove the tank and expose the servo pump. pull the hairpin clips so you can pull the rigid brake lines
Pull the filter screen out of the pump
Suck out all the brake fluid you can
Undo the upper bake line fitting at the jumper on the right side of the head stock
Old rigid brake lines removed and new jumper (I had the jumper already made.)
Install the jumper in the crossover fitting and snug. Front circuit is now bypasses
A piece of tape over the opening where the old rigid brake line was
Put the old rubber boot back over the tape to seal off the pump
Undo the hairpin clip for the rear circuit
Undo the rigid brake line at the rear master cylinder and remove the old rigid brakes line. You will have to cut the one in the middle to get it out.
Now onto the rear jumper. Since BMW uses a special fitting here, we need to harvest one end of an old brake line and then bubble flare the other to make a jumper/adapter
Rear jumper bubble flared and ready for final tweaking/fitting to get it just right
Rear jumper installed
Bleed the rear caliper and 2 hours and 2 minutes later you're all done and have excellent non-ABS brakes
Some people remove the ABS pump as it does lighten the bike by about 7 pounds but if you do this you will have to remove the "brain box" on the right side and then make a waterproof cover and mounting bracket. If you do not reuse the brain, you will lose brake lights and speedo function. Haining gone through the trouble of removing the ABS pump, making a cover plate and mount its it far easier to abandon the ABS pump in place. Then it is sealed and sturdily mounted, and you retain brake light and speedo functions.
Cheers,
P-14
