02 R1150R intermittent rear ABS fault

I am hoping someone can help shed some light on this intermittent and annoying problem. I have recently started to experience a problem with my rear ABS circuit. Only after parking it for a day at my work on a fairly steep incline on it's centerstand, i go to leave for the day, start the bike and the ABS light will flash fast.
On many occasions after a few minutes of riding i will come to a stop, shut it off and restart it and the fault will clear. The fault only affects the rear circuit and not the front. The front brakes still work fine.
I have tried bleeding the ABS rear circuit several times and this has not solved the problem. It does not happen every time, only about once or twice every 8 to 10 work days. If there is no air in the ABS unit, could it be a faulty rear wheel sensor? If so, how do I check it? I have also read that a weak battery could cause ABS faults but my battery is brand new.
I appreciate any help that anyone can give.

Yes possibly the sensor. The sensor is simply bolted to the top right side of the final drive housing with a single bolt; unscrew that, gently slip the line out of the little holding clip (just forward), and it pulls straight out.
Typical failures are either 1) oil on the sensor, which may indicate a leaking seal inside the drive (and of course impedes the ability of the sensor to see the wheel rotations), or 2) the gap between the sensor and the ring is wrong. (Sorry I don't have the spec handy, bit it's a very small gap.)

A brand-new battery can be faulty... Give it a trickle charge with a known good charger for at least a full day; maybe take it to your local auto parts store and have it load-tested - do NOT let them "charge" or boost it first (as is common practice), you want to see it in an actual as-is condition.

When you bled the rear brakes, did you include the circuit up there inside the ABS pump?
If you bleed manually (no Mity-Vac or equivalent), it's quite easy to still have a little air in there.

slowrider60 said:

I am hoping someone can help shed some light on this intermittent and annoying problem. I have recently started to experience a problem with my rear ABS circuit. Only after parking it for a day at my work on a fairly steep incline on it's centerstand, i go to leave for the day, start the bike and the ABS light will flash fast.
On many occasions after a few minutes of riding i will come to a stop, shut it off and restart it and the fault will clear. The fault only affects the rear circuit and not the front. The front brakes still work fine.
I have tried bleeding the ABS rear circuit several times and this has not solved the problem. It does not happen every time, only about once or twice every 8 to 10 work days. If there is no air in the ABS unit, could it be a faulty rear wheel sensor? If so, how do I check it? I have also read that a weak battery could cause ABS faults but my battery is brand new.
I appreciate any help that anyone can give.

Click to expand...

Paul, Thanks for the info on checking the sensor. My battery is fully charged, no problems turning over. i am not leaking anything from the final drive. I have bled the rear circuit at the ABS unit. i will check and clean the sensor. here is hoping!