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Lopen is sneller....
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Discussion Starter · #1 ·
I got some nice Hope two piece rotors for my boss a couple of months ago. They look pretty bling and she did not experience any trouble with them. In fact the only down side was that I could not hear anymore how long I had to wait.

Last weekend we went to the PassPortes for some lift assisted fun. After almost every DH run her rear break would drag so bad you could hardly move the wheel, bien sur after cooling a couple of minutes it got better but never drag free like before.

Has anyone similar experience with the two piece rotors (the normal ones never had this problem on park days) or is this just a sure sign to give the brakes some love and DOT5?

Here is a picture of my boss exploring some trails at Portes du Soleil.
 

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Uzzi said:
...After almost every DH run her rear break would drag so bad you could hardly move the wheel, bien sur after cooling a couple of minutes it got better but never drag free like before....
Sounds like you have a bit too much fluid in the system. On a long downhill, the fliud heats up and expands. If there is too much fluid in the system, and the expansion resevoir has no room for the extra volume, it causes the caliper pistons to extend, applying the brakes. When the fluid cools, the pistons will retract. Resetting the slave pistons (manually pushing them back) will probably remove the parasitic drag, since the pistons simply did not retract to thier original position. I don't think the 2-piece rotors are to blame.

Cheers,

Tom
 

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Lopen is sneller....
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Discussion Starter · #3 ·
Thanks!

Can I best let go some fluid at the brake piston or at the lever? I think I will bleed them anyway is there a trick to make sure I don't have to much fluid in the system again?
 

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Uzzi said:
Can I best let go some fluid at the brake piston or at the lever? I think I will bleed them anyway is there a trick to make sure I don't have to much fluid in the system again?
I don't have Hopes, so I'm not familiar with Hope's bleeding procedure. With Maguras or Shimanos, you can open the resevoir, push the slave pistons all the way back, then close the resevoir using the recomended proceedure to eliminate any air. Maguras come with a spacer to put into the caliper to hold the pistons open during bleeding to ensure you don't put too much fluid in. With Hayes, we've cracked open the bleed valve, pushed the pistons back, and closed the valve being careful not to let air in - which was a common fix when you replaced worn pads, and had previously bled the brakes with worn pads and without pushing the pistons back.

Cheers,

Tom
 

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Lopen is sneller....
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529 Posts
Discussion Starter · #5 ·
When I was working on the brake, planning on letting go some fluid I discovered the retainer spring had snapped (well that's what I think). Could this cause the dragging or should I still let go some oil...well I guess I try a new spring first...
 

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It's difficult to diagnose problems over the web, but by the sounds of the symptoms, it still sounds like you have too much fluid in the system, the spring clips are only supose to keep the pad from rattling or rubbing after the slave pistons have retracted (they are not desiged to retract the pistons).
 
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