Originally Posted by
Amt0571
They also tend to have sticky pistons when the wear adjuster is at a medium to high wear setting (you'll notice it because only one pad retracts and the other sticks to the rim). This is the worst issue to fix, you have to clean the pistons on the calipers, and sometimes force the stuck piston to work by holding the working one with your fingers. I've notice that if the bike is parked on the sun, the piston most exposed to the heat tends to stick.
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I have an HS33 in the shop right now with exactly this issue. The right side piston was stuck. I was able to free it up by clamping the left pad and allowing the pressure to force the right pad to move. Through many repeated cycles of applying and forcing the piston back, I was finally able to free it up so it now retracts freely.
The bike it is off of is stored in a highly corrosive environment in a basement parking garage right beside the lake. I don't know if that is a factor.
The owner had me replace it with a cable actuated V brake because he figured it was toast. He was overjoyed when I told him I got the Magura working because it was so superior when it was working.
This is the bike. He needs all the braking power he can get.