Rear brake sticking cali 1400

[lucian]

Well, I feel obligated to report my first ever problem with my 2014 custom 14.(12,000miles) Took it out for a ride today and immediately noticed the rear brake dragging. Bike had not been ridden for a couple of weeks but noticed no issues last time out. Any way, I have pulled the rear caliper off and popped both pistons out and will clean them up and re install and see what happens. My concern is if it could be related to the abs pump and not just as simple as a sticking caliper.The front brakes are  unaffected. Also I am wondering if there is any special process for bleeding the rear with abs? Appreciate any and all advice, thank you   dave

[Sasquatch Jim]

 It sounds like you are going the right direction by cleaning all the moving parts.  It doesn't take much dirt or corrosion
 to make a rotor drag in the caliper.   I've never had a non skid device so I don't know about them.

[apex1397]

Check to make sure heat shield on right head pipe is not interfering with brake pedal movement. Seen it before.

[lucian]

I have it reassembled, cleaned up and lubed all caliper parts,bleed it out and went for a test run.No improvement, seems as though it must be an abs issue. It is like once pumped up the pressure wont relieve, damned if I know. I will call the good folks at Seacoast and see if they can have a look. Thanks for the response and I will pass on anything I find. I am just glad it happened hear instead of on a road trip. I did find it possible to gently pry the pads open with my jack knife when it happened and ride on with just using the fronts, but when reapplied the rear will stay pressurized.

[Vasco DG]

Make sure the plunger hasn't come loose and extended on the lever and also make sure the return springs are strong enough and the lever is returning to the end of its travel. Highly unlikely to be ABS related. Far more likely to be due to the piston not returning far enough to uncover the priming port.

Pete

[lucian]

Will do Pete , thanks for that. Fortunately the the griso remains bullet proof.

[lucian]

Just took a look at the pedal and master cyl. and the lock nut on the plunger is tight, and the return spring is good , but when the pedal is retracted the plunger flops around in the end of the master cyl. with about a quarter of an inch of free play. I can't tell if it is because the cylinder isn't returning all the way or it was adjusted that way, but it seems excessive. Tomorrow I will try and muscle that behemoth on the lift for a closer look. Looks like a real pos boot that protects the plunger and cylinder bore ,and given where it is located facing forward I wouldn't be surprised to find it full of who knows what in there. Some new pads are in order too as it pretty much toasted them. Thanks for the help, I will report back tomorrow. dave

[lucian]

Had a look at the master cylinder today and found no issues. A BMW mechanic told me that it could likely be that the pads have worn too thin. Which in turn allows the rear caliper pistons to protrude to the point of being able to cock from the rotational force while braking and then stick. Will try some new pads before I loose any more sleep over it. Cali owners keep an eye on your rear pads as they seem to wear extra fast on this bike. Fronts are virtually like new and the rears are toast. I was quick to assume that the sticking toasted the pads when in fact the pads may have been worn to the point of causing the sticking. The old chicken and egg thing again. Will have an update when I find some new pads.  dave

[lucian]

Problem solved. Slapped in a new set of pads and took it out for a romp with no more issues. Although I dismantled the rear caliper and cleaned things up, I think the bmw guy may have been right. I guess I should not be surprised that a 700lb. bike eats rear pads for breakfast. Clearly I must try to even out the wear with the fronts more, but that nice big foot brake is just so easy. Surprisingly the old pads still have 1/16  of an inch of pad left on them but they still caused the brake to stick after I had cleaned up the caliper. I will probably replace the rotor with the next rear tire as it is starting to show a wear track, which I suppose would also incrementally add to the piston protrusion. Any how I am glad it was an easy fix for a change. Thanks for the input and cali owners keep a close eye on your rear pads.

[Caffeineo]

Thanks for following up with the solution. 
Glad it was an easy fix.