Stiff hydraulic lever and slow-to-return pistons

The answer (just resurrecting

The answer (just resurrecting this old thread) was; flow  slightly restricted due to a burr where the hose was cut. Removed burr and everything was fine.

guyrwood wrote:

Interesting, glad you got it sorted. I’ve literally just ordered the exact same brakes, any hints and tips for fitting and bleeding them?

Step 1: buy the kit from here:  http://www.epicbleedsolutions.com/

Step 2: follow youtube videos. But in summary:  open bleed port on shifter and thread in the threaded syringe  (A) (without the plunger). Full that syringe half way up. Attach syringe (B) and hose to calliper bleed port and pull down a little bit of a vaccum with it. Open up the calliper bleed port and pump the brake; the fluid will be pumped from the top syringe at the shifter to the bottom syringe at the calliper. Keep going, replacing the fluid at syringe A  as needed. Throughout, tap the hose, shifter and calliper to encourage more air out. Once done, close the calliper bleed valve and pull down a vaccum on syringe B so it slurps up the fluid as you pull it aray from the port. At the calliper end use synring B to empty out the fluid that remains in syringe A. Unscrew syringe A and wipe away fluid. Screw in the bleed screw. Done.

I recommend doing this with the wheels off, pads out and callipers detached from the frame; that way you can angle it all around to ensure the last bubbles are removed.

For anyone following this, it

For anyone following this, it turned out to be a tiny piece of swarf in one of the brass fittings that are pressed into the hose.

Thanks. Good advice!

Thanks. Good advice!

However, there’s no air on this system; I’m absolutely certain of it. Like you I also do various tricks to get the air out including removing the callipers and putting them at an angle that moves the air to the bleed hole as well as suspending the frame as an angle to get the air past the bottom bracket.

The lever isn’t soft – the brake responds immediately and in the same way as the other lever. It also – unlike if it had air in it – bites hard without sponginess beyond what you’d expect from the designed elasticity of the system. The issue is purely that it’s stiff and returns slowly.

They move out some amount for

They move out some amount for sure and I can pump them out a good few mm with a few pulls – sufficiently to give me enough exposed cylindrical area to get some brake oil around the pistons. The difference between them and the fronts is that the fronts move out under pressure and instantly retreat about half a mm when I let go, but the rears retreat the same distance much slower (as mentioned above it takes about a second). Due to the slow retreet if I have the rotors in subsequence pumps of the lever just ram them harder against the rotors and the levers become stiffer earlier.