Bleedin formula brakes

[ishaw]

No, I'm not missing an g, well maybe I am.

I'm having trouble with a set of formula Rx brakes. I've had them since they were new, and when originally fitted to my bike, they were great. The bike has been mothballed for a few years, I have been putting air in the tyres and pumping the brakes every now and again, but the brakes have developed an issue at both ends, very little piston movement and they are tight on the rotors.

I've bled the brakes but they still remain as they were before the bleed, I've even tried removing fluid to try and get the pistons away from the rotors but nothing seems to change.

Anyone had this issue and solved it?

 

[novocaine]

Sticky seals.

They expand thanks to wet Dot4 fluid.

 

[ishaw]

That's a bummer and surely a design flaw. I don't suppose you know if they can be rebuilt. I am not familiar with these brakes, have hopes on all my other bikes, know a little about servicing them, but not formula ones.

 

[novocaine]

Not a design floor, doesn't happen in use or with fresh fluid, only when left for a long time.

Dot4 is hygroscopic, it absorbs moisture.

Drain them, strip them, clean the seals and leave them to shrink back. Might take a few days. Rebuild with a suitable brake fluid proof grease on the seals.

If you can find me seals that would be win.

I only have 2 spare sets left for a b4 brake, when they are gone so are the brakes.