No rear brake

[SANDPSYCHO]

I have a 2011 and due to 2 cross county moves and life I hadn't ridden the bike since 2020. So now life has settled down and I wanted to get out and ride. I bought new tires, changed the oil and installed a new set of front brake pads. I take it out for a ride and at first the brakes has a stranger vibration. I figured it was the front pads seating in and it went away in less than a quarter mile. I hit the first gas station and notice the rear brake lever goes all the way down and doesn't hold the bike on basically flat ground. So the ride is over and I head back home.

I start reading up on possible reason and I keep seeing issues with the ABS pump and it's $1100 and $1300. So I'm thinking down another the rabbit hole I go. Is this likely the issue? How much is it going to cost on avarge if I do the work myself? What would a dealership/repair shop charge? I can't help but wonder how much am I going to have to spend to get a bike that's worth $5K ish road worthy or just cut my losses.

[lather]

Brake fluid should be changed every 2 years as it absorbs moisture and clogs up the brake system and the moisture and damge rubber parts. If it has not been changed since 2020 that is likely the problem. A thorough flush and new fluid is what I would try but you likely will need to replace the seals in master and slave cylindars. Good luck!

[maxtog]

Brake fluid should be changed every 2 years as it absorbs moisture and clogs up the brake system and the moisture and damge rubber parts. If it has not been changed since 2020 that is likely the problem. A thorough flush and new fluid is what I would try but you likely will need to replace the seals in master and slave cylindars. Good luck!

I was going to post similar.  I would first change fluid with flush on both front and rear.  It is a good starting point, but I wouldn't hold out hope that it is going to fix a problem where the rear brake pedal goes completely limp.

Also, this isn't likely an ABS problem unless you see an error code on the screen at some point.  The computer monitors that pretty regularly and I think performs some forms of self-testing as well.  So, OP, I wouldn't jump to that conclusion.

[Freddy]

The problem may be that the rear m/cyl piston is stuck with crud part way down the bore.  Get a new one off ebay - ZX 14 is the same. They are good quality despite the cheap price.  Remove the old one and open it up to find that it's full of crud which you don't want to pump into the ABS unit.
Use the original clevis yoke on the linkage and adjust it correctly before fitting the split pin.

[SANDPSYCHO]

I appreciate the advice. I'm going to start with Freddy's suggestions and try a new master I'll order tonight.