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Discussion Starter · #1 ·
Hello, I would appreciate any help you could give me.

My brother is gone for the summer so I tried riding his 2003 Norco Torrent hardtail bike. It was fine when I rode it about a mont ago. However, when I tried yesterday, I found that while the rear wheel spun nice and smoothly, the front wheel seemed semi-jammed.

I got a screwdriver and unwound the front Hayes HFX 9 hydraulic 8" brakes. I found that the two pads that move closer to stop the wheel were waay to close together. Now I stuck a flat screw head and spread them apart, but when I pull on the brakes again, they come together and don't move back. Now I can't even put the pads back onto the disk.

So how would one seperate the two pads further apart? Any help would be greatly appreciated. Pics are available if necessary.
 

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HFX9 Brakes are....

self adjusting for pad wear. I.e. as the pad wears and gets thinner the pistons adjust for it by moving further out. But there comes a point where if the pads get too thin the pistons move too far out and won't retract anymore or won't retract completely as they should. In this case it's simply a matter of pushing the pistons back (as you did previously) and replacing the old worn pads. The way to check is to remove the pads and measure them. If the pad thickness (including the backing plate) is less then 3mm, they're worn out.

But there is another possibility, sticky pistons. This can happen through use. Dirt and crud gets in there and causes the pistons to stick (not retract). This requires removal of the pistons, cleaning, lubing etc.

If you know what you are doing either fix is realatively simple. If you don't know what you are doing, take it to a shop and have them do it. You can screw things up pretty good if you don't know what you are about. Either way it's most likely fixable. Just don't get in over your head and screw things up worse.

Good Dirt
 

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WendysBurgers said:
I got a screwdriver and unwound the front Hayes HFX 9 hydraulic 8" brakes. I found that the two pads that move closer to stop the wheel were waay to close together. Now I stuck a flat screw head and spread them apart, but when I pull on the brakes again, they come together and don't move back. Now I can't even put the pads back onto the disk.

So how would one seperate the two pads further apart? Any help would be greatly appreciated. Pics are available if necessary.
It sounds as though you're squeezing the brake lever without the rotor in between the pads. Don't do that.

Try this:

1) Remove the pads from the caliper. The left pad is slightly different from the right, so keep track of which is which. If the pads are too close together to make removal difficult, use your flat bladed screwdriver to gently pry the pads apart. Once the pads are removed, do not squeeze the brake lever. If you do, you'll most likely push one of the pistons out of its bore and you'll end up with brake fluid leaking all over the floor. (I learned this the hard way.)

2) Using a 10mm box end wrench (or something close to this size), press both of the pistons back in their bores. Be careful not to damage the pin in the center.

3) Put the brake pads back in the caliper.

4) Put the wheel back on.

5) Check that the wheel spins smoothly prior to squeezing the brake lever. If it doesn't (and if you've properly pushed the pistons back into their bores), the caliper needs to be recentered.

6) Squeeze the brake lever and release; verify that the wheel still spins smoothly afterwards. If not, examine the position of the rotor with respect to the pads. You ought to be able to see a sliver of light between the rotor and each pad. If you only see a gap on one side, try recentering the caliper. If you don't see a gap on either side, take the bike to your LBS and have them look at it.
 

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Discussion Starter · #4 ·
Thanks for your replies. I will try to repair this myself to the most reasonable extent as possible, and take it to the shop if I can't.

So, I did remove the two pads from the caliper. I am pretty sure they aren't wore out, they look thick enough (front brakes are rarely used).

Could I get some advice on how to clean/lube the part of the brake that moves in and out? Would I just apply some oil there?

And here's the troubling part. I tried to assemble the pads back on, to see if they would work, but I just can't figure out how to lock the pads in place. I looked at the manual from the Hayes website, but it is not helpful. I've attached pictures to show what I am working with.

I was working with the outer brake pad first since thats what the manual says. I tried putting the metal pin in first, hooking it to the metal thing inside the caliper. Then I put the pad on, and I know that I have to hook the pin onto the pads, but it is impossible. Is there another way of doing this? I know my description may sound confusing, I hope you understand.
 

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WendysBurgers said:
Could I get some advice on how to clean/lube the part of the brake that moves in and out? Would I just apply some oil there?
Wipe as much dirt as possible away from the area. You can use a bit of rubbing alcohol if you want to get it really clean. I wouldn't try lubing it since you really won't be able to get much lube to penetrate the area and you don't want excess lube sitting around on the outside where it'll do more harm than good. (It'll just attract dirt.) If you must lube the pistons, use some brake fluid (DOT 4, I think). Just make sure you don't have a lot of excess lube laying about. It'll contaminate the pads which will make them squeal and, more significantly, will diminish your braking power.
And here's the troubling part. I tried to assemble the pads back on, to see if they would work, but I just can't figure out how to lock the pads in place. I looked at the manual from the Hayes website, but it is not helpful. I've attached pictures to show what I am working with.
You need to reattach the retaining springs to the pads. Once that's done, the pad assembly slides over that center pin and will snap in place. Sometimes, it takes a few tries to get it in the correct position. If you need it, I can post a picture of a pad with the spring attached.
 

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Discussion Starter · #7 ·
Ok. thanks for the reply.
So what you are saying is that, for me to put the pads back in, the metal springs have to be preattached? (shown in the picture)

What I've been trying is: putting the springs in first, then putting the pads on, and trying to clip the bottom using a thin metal wire.
 

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Discussion Starter · #9 ·
OK. I cleaned everything with rubbing alcohol and successfully put the pads back on, but the gap is still to small to allow the disk to rotate. Is there a more permanent way of making sure that the pistons stay back?

I tried pushing them in with the flat side of a screwdriver, but they just end out sliding out a bit.
 

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WendysBurgers said:
OK. I cleaned everything with rubbing alcohol and successfully put the pads back on, but the gap is still to small to allow the disk to rotate. Is there a more permanent way of making sure that the pistons stay back?

I tried pushing them in with the flat side of a screwdriver, but they just end out sliding out a bit.
I would try to push the pistons back into their bores a couple more times first. When I've done it, I've found that pushing one side in will frequently push the other side out. The box end of a 10mm wrench works well because you can push one side in while bracing the wrench against the other piston. But, again, take care to not damage the center pins upon which the pads are secured.

After doing this (and replacing the pads plus wheel), and prior to pressing the brake lever, the wheel ought to spin freely in the caliper. If it ceases to spin freely after squeezing the brake lever, you have other problems. (These problems could have to do with the centering of the caliper, or worn piston seals, or could even be a master cylinder problem.)

It may be too that there's too much fluid in the system. You can easily remove a bit of it by loosening the bleed valve a little, taking care to catch the fluid that spurts out with a towel. Be ready to tighten the valve again quickly after some of the brake fluid squirts out. (The bleed valve is on the caliper and has a small rubber cap on it.) Take care to not get the DOT brake fluid on your skin or on your frame or fork, as it'll eat the paint away, and will cause skin irritation. Have some water ready to neutralize any brake fluid that ends up where you don't want it. Also, wear safety glasses. (I had some fluid squirt at my face one time when messing around with my brakes. Fortunately, I was wearing safety glasses.)
 
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