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Discussion Starter · #1 ·
Any one have any ideas? Currently my BB7s are giving me no stopping power what so ever. I just replaced the pads and it takes all of your strength in all your fingers just to barely get the rear to lock up. No matter how hard I pull on the front it barely provides any power and is miles away from being able to pop the rear up.
Before I replaced the pads they were kind of doing this though I didn't think much of it because I knew I had very little of the pads lift.
Also my last ride it poured down riding and the trail is basically like riding on a beach so I and the bike were covered in sand. Could the sand have done anything?
I cleaned the rotors with some degreaser, I'm going to try some alcohol in the morning.
I also sand the rotors and pads to see if that would do anything, as well as center the calipers.

Any input would be nice. I'm suppose to ride with some people tomorrow but I can barely stop myself at a slow pace on flat let alone steep fast trails.
 

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local trails rider
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tb2007 said:
I cleaned the rotors with some degreaser, I'm going to try some alcohol in the morning.
What kind of degreaser?

Do the pads press on the rotors OK?

I am running a set of BB5 on one bike and they work fine without any pampering. There have even been a few drops of chain lube on the disc but the only real care has been some soapy water and a rag.
 

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Super Moderator
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the pads weren't braking well, because they weren't broken in....


as perttime, I now ask what kind of degreaser you used...as you may have contaminated your perfectly good pads....
 

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Old man on a bike
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tb2007 said:
Any one have any ideas? Currently my BB7s are giving me no stopping power what so ever. I just replaced the pads and it takes all of your strength in all your fingers just to barely get the rear to lock up. No matter how hard I pull on the front it barely provides any power and is miles away from being able to pop the rear up.
Before I replaced the pads they were kind of doing this though I didn't think much of it because I knew I had very little of the pads lift.
Also my last ride it poured down riding and the trail is basically like riding on a beach so I and the bike were covered in sand. Could the sand have done anything?
I cleaned the rotors with some degreaser, I'm going to try some alcohol in the morning.
I also sand the rotors and pads to see if that would do anything, as well as center the calipers.

Any input would be nice. I'm suppose to ride with some people tomorrow but I can barely stop myself at a slow pace on flat let alone steep fast trails.
What did you do to bed in the new pads? Each time you clean the rotors you're starting over with the bedding of the pads. Making sure your calipers are properly positioned is a good thing.
 

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Most degreasers leave a nasty film of stuff which is sometimes sticky or even slightly greasy, the only things that should some near your rotor is water, mud, pads and denatured alcohol. BB7s are also very sensitive to good cables, you need new ones with new housing to get max power. I was surprised how much mine improved when I changed some really old cables (2/3 fold increase in power on my commuter)
 

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I think n3 is on to something regarding the cables. If you were having the same/similar problem before you replaced the pads and cleaned the discs, I'd suspect loose/improperly-adjusted cables.
 

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narCOTIC
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It's the degreaser you used mate. Get some alcohol on the rotors, and sand out the pads. Then make sure you bed your pads in good (i usually take them on a couple of leisure rides with normal braking until they feel sharp).
 

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Dirt Deviant
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90% of degreasers will leave an oil residue, especially the citrus ones.
Fast drying degreasers can sometimes be used on rotors such as Clean Streak....but not all are good.
Sounds like the orange peelz contaminated the pads and rotors.
Also, whenever you clean the rotors and or sand the pads the brakes need to be bed in. this usually takes 30-50 hard stops from a good speed per brake.
Whenever you change to new pads they need the same bed in process.
One thing that hasn't been mentioned is what kind of levers are you using with your brakes?
Also, using a compressionless housing for the brakes is a must with any mechanical brake system.
I run a BB7 with a 6" rotor (160mm) on the front of my commuter bike and I weigh close to 300lbs. I can easily flip myself over the bars with this setup, so it isn't the brake system, rather the setup.
 

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Discussion Starter · #10 ·
I'm using the Avid Fr-5's. Lets say that it was the degreaser what should I do to the pads. I already tired sanding them, should I bake them? I clean the rotors with some alcohol, should I bake them as well?
 

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Dirt Deviant
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Heating up the pads works really good. If you have a small torch that works even better.
But I suppose the oven deal works good too. I've only used a torch to do so, but as long as you get em hot enough to burn off the oils it works. I'd say 400F until they no longer smoke should do it.
As far as the rotors, don't need to heat them, but give them a good scrubbing with alcohol. Denatured if you have it. If not 99% rubbing works great.91% minumum. Use fresh clean paper towels for scrubbing the rotors.
 

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You should be able to test the pads by just sandwiching them around the rotor with your fingers, and seeing if you can get them to grip by pressing your fingers together. If they grip, then the problem is not the pads/rotor.
 

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Unshaven Yak
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When I and most of my riding buds ran BB7's, we used to squirt a bit of water on the disc and caliper (pads) and that would greatly speed up the bed in process and give the pads some bite almost immediately.

Totally concur with what others have said about the cleaning solution....never tried putting degreaser on anything brake related but I wouldn't expect great results. Dish soap and water are the only elements to have graced my discs for cleaning.

Also, I take it you had to reset the pad-adjustment knobs to accommodate the new pads, that could play into the problem if you set them up for good feel in your garage; we always had to tweak the feel once we got moving.
 

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ballbuster
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Are....

... you adjusting the pad contact point with the lever barrel adjuster? Well, don't!

I see this on Avid BBs all the time. Adjust the lever barrel adjuster to take all the slop out of the cable and housing while the brake caliper's actuator arm is in the fully open position.

THen take some duct tape and mummify the barrel adjuster so you won't be tempted to ever touch it again. Okay, you don't need to do that, but you get the idea.

Adjust the contact point with the red knobs on the caliper. Also, use the red caliper knobs to adjust for pad wear.

If you adjust the pad contact point with the lever barrel adjuster what happens is that the caliper actuator arm eventually ends up bottoming out on the caliper body. That means you can pull the lever with all your might, but the pads will only partially engage if at all.

Oh, and if you are going to use degreaser, only use something like Brake Kleen or something specifically for brakes.... or use 99% rubbing alcohol.
 

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Discussion Starter · #15 ·
Okay still nothing. I have cleaned rotors with with alcohol and soap/water. Baked pads in oven just in case they some how got oil on them. Pads are all adjusted correctly without use of barrel adjuster.
What now?
I guess brake cables or caliper problems?
 

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Legend
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When I glazed my Hayes brakes (sounds like your problem) I do this:
1. Degrease rotor with alcohol
2. Sand braking surface with 180 grit sandpaper until the rotor looks uniformly scratched
3. Put some finer grit sandpaper on the ground (sandpaper side up) and rub my pads on it; this cleans off any glaze thats on there. Dont't be shy, this EATS pads, just so you know, but a few back and forth strokes and the pads should look like "new".
4. recenter the caliper. I would pay special attention to whether the pad touches the rotor at the bottom before the top, because that would indicate a misaligned rotor.

Every time I have had to do this (due to my stupidity, this has been relatively often) they work perfect again (of course, once they're re-broken in).

Cables COULD be the problem, but if you can, without the wheel inside the rotor, actuate the brakes with relatively little force, then i'd go my 4 step programme.
 
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