I have a problem on my rear formula brake that the piston is not being pushed back in to its caliper,(and is constanly rubbing) the spring in the pads seem ok, I have taken the pads out and sprayed the piston with gt45, when i squeezed the brake lever while the pads were out, only one piston was coming out, so I was only able to put a bit of lube on one piston, ( i hope that makes sense) any one any ideas

thanks
craig

TBH – I have zero experience with Formula brakes but ……..

Can you pop the piston out by holding the other one in and clean/lube it? – use silicone grease, red rubber grease or some brake fluid

not GT85

clean the gt 85 off – it might ruin the seals.

the spring in the pads is only to stop rattles.

You need to lube the seals properly – work the piston in and out ( holding the other one in if needed and get some brake fluid / rubber grease on it You don’t need to remove the piston completely unless it is totally seized

I expect the piston has probably dried out, I use a cotton wool bud and brake fluid to re-oil it, then it works for a while. 😉