Code R brakes question

Swissrider

Well-known member
Nov 1, 2018
362
381
Switzerland
I accidentally pumped out one of the pistons in my code R brakes today. I managed to get the piston back in but as I had lost some fluid I had to bleed the brakes, which was overdue anyway. Having bled them, I am having a problem with brake rub - the pistons don't retract enough and there is virtually no play at the lever. The brakes work well but are being slightly applied all the time. I also bled the back brake and this is fine. I have taken the pads out, pumped the pistons our, lubricated them with brake fluid, pressed them back in and replaced the pads but the problem remains. So, I don' think the pistons are sticking. Should I let a bit of fluid out? And if so, at the lever end or the caliper end? Thanks.
 

blueglide

Member
Jan 2, 2021
89
98
Tucson, AZ USA
Make sure your brake caliper is centered. They can be adjusted slightly inward or outward on the brake caliper mount to make sure they are equal distant from the rotor. Mine was doing the same thing and a slight adjustment to get them centered in relation to the rotor fixed it.
 

Clubby

Active member
Oct 3, 2020
159
132
Tayside
Sounds slightly overfilled. Can happen if you’ve bled with wrong size bleed block.
I’d undo the lever bleed port and see if any fluid leaks out. Don’t remove completely, but if there is too much fluid the excess should escape as you loosen it. Other possibility is just a thick set of new pads that need ridden in a bit.
 

Swissrider

Well-known member
Nov 1, 2018
362
381
Switzerland
I did take the lever bleed port screw out and no fluid came out. Maybe I need to push the pads apart (they are not new - they have had three days of fairly intense use - 2500m of descent) to release some fluid. I guess the worse that can happen is that air gets in and they become spongy or the lever comes all the way back to the bars. Many years ago I had a problem with binding brakes and just released a bit of fluid which cured the problem. I know it is not the capliper adjustment. I'll post how this goes!
 

Mikerb

E*POWAH Elite World Champion
May 16, 2019
6,143
4,673
Weymouth
Yep..I would release the lever port and push the piston all the way back, which will probably push a little fluid out.
 

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