UPDATED 9/1 - Took the caliper apart and cleaned everything, lubed with DOT4 and put it back together. The interior was grubby and the fluid was disgusting. The fluid in the balance of the system is fresh but this wasn't getting fresh due possibly to some dirt, who knows? Began the bleeding process again and no bubbles, full pedal and plenty of pressure and that's when I first noticed the small pin prick in the OEM rubber brake line coming from the ABS. Each push of the pedal now resulted in a fine spray of brake fluid and that is likely what caused the loss in the first place.
OEM replacement is also rubber and I'm waiting on word from Galfer, 20 minutes from Reno, Nevada, to let me know if their part number is good for ABS. If so, I'll do a stainless wrapped PTFE hose this week and be back in the road. Thanks for looking.
ORIGINAL POST - My first post on my first BMW motorcycle, a 2002 F650GS ABS, 29k miles when I got it and I'm in the process of doing things to make sure it's good to go.
I noticed the pads were at their wear limits (or close) and I replaced the front & rear pads this last week.
I noticed the rear pedal was sinking further than it should BEFORE the pad install. AFTER the install the pedal sinks to the stop and there is no movement in the caliper and I can spin the rear wheel. When I installed the pads the caliper pistons moved readily and allowed me to slide them into place. The piston apparently moved out again but wouldn't apply any pressure.
Thinking fluid is moving past the piston in the MC I then rebuilt the rear master cylinder with a Brembo parts kit replacing everything inside. Re-bled and got some air on every small push and then I chose to reverse bleed from the caliper upward and got rid of apparently all the air yet still nothing to call pressure. The pedal goes to the stop. Clear bubble free fluid on each push and no air but also no brakes.
Is this the ABS causing the frustration? I don't have these problems in front so I'm baffled. What should I be looking at and is this a job for a dealer/marque specialist? Or am I simply missing something? I've read the Haynes and read the Brembo rebuild notes and I'm at a loss for what to do next.
The bike is red if that makes a difference.
OEM replacement is also rubber and I'm waiting on word from Galfer, 20 minutes from Reno, Nevada, to let me know if their part number is good for ABS. If so, I'll do a stainless wrapped PTFE hose this week and be back in the road. Thanks for looking.
ORIGINAL POST - My first post on my first BMW motorcycle, a 2002 F650GS ABS, 29k miles when I got it and I'm in the process of doing things to make sure it's good to go.
I noticed the pads were at their wear limits (or close) and I replaced the front & rear pads this last week.
I noticed the rear pedal was sinking further than it should BEFORE the pad install. AFTER the install the pedal sinks to the stop and there is no movement in the caliper and I can spin the rear wheel. When I installed the pads the caliper pistons moved readily and allowed me to slide them into place. The piston apparently moved out again but wouldn't apply any pressure.
Thinking fluid is moving past the piston in the MC I then rebuilt the rear master cylinder with a Brembo parts kit replacing everything inside. Re-bled and got some air on every small push and then I chose to reverse bleed from the caliper upward and got rid of apparently all the air yet still nothing to call pressure. The pedal goes to the stop. Clear bubble free fluid on each push and no air but also no brakes.
Is this the ABS causing the frustration? I don't have these problems in front so I'm baffled. What should I be looking at and is this a job for a dealer/marque specialist? Or am I simply missing something? I've read the Haynes and read the Brembo rebuild notes and I'm at a loss for what to do next.
The bike is red if that makes a difference.
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