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Just got Avid BB7s for my rigid Redline Monocog. Great. Installation seems straightforward. Until I spin the rotor in the brake body, and get consistent rubbing, no matter what I do. All adjusters are opened up as far as they'll go. So that's puzzle No. 1.

Then on the front (rigid) fork, when I drive the install bolts all the way in, the tip of the screw actually catches the rotor as it spins. Too long? Shave down the bolt? Washers? WTF?

Any and all tips welcomed.
 

· Just a flesh wound
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Washers

Maybe the bolts are rubbing the rotor all the time. If you open the BB7's all the way you would need a very thick rotor to rub all the time, unless it was skewed badly. Or maybe the caliper is hitting the outside edge of the rotor. Do you have the right adapter for the rotor size? Is the adapter upside down? Is the rotor compatible with the bb7?
 

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I have BB5's on my Redline Flight, and don't have any of those issues. I have had several sets of BB7's, have them on my Niner right now. I'm guessing that you did the installation as per the instructions, they do not self adjust so alignment is very important.

I would guess you could fix the issue on the front fork with washers, depending on how bad it is, I'd definitely try a washer before cutting the bolt. I do have one washer on each bolt for the BB5 on the rigid fork on my Flight.
 

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You need to have a really close look at the calliper, positioning yourself so you are looking into the 'slot' that the rotor runs through. Look at the rotor, and it must run throught the middle of this area, but also it shouldn't be out of line, either height-wise or length wise. There is not a brake made where the rotor won't run through it without rubbing if its set up perfectly. You just need to figure out how yours is misaligned.

Some pics for us will help a lot
 

· Meh.
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The bolts are probably too long because your disc tabs may be thinner. Use a washer. It's no big deal.

Can you see which pad it is rubbing on? It is possible that you have maxed out the side to side adjustment of the caliper and either the rotor or the adapter needs to be spaced over.
 

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I don't want to sound like I'm asking a stupid question, but have you followed the Avid installation instructions? Here is what they say as far as aligning the caliper (to which I've paraphrased a bit).

A. Make sure the CPS bolts are loose. (The CPS bolts are the bolts that attach the caliper to the mounting bracket.)
B. Turn the inboard (closest to the wheel) knob clockwise until it pushes the ro-
tor so it is in a position that is closer to the outboard side. Note that the rotor should not be centered between the walls of the caliper body. The spacing should be 1/3 on the outboard side, 2/3 on the inboard side.
C. Turn the outboard pad adjustment knob in until it is firmly squeezing the rotor against
the inboard pad – thus immobilizing the actuating arm. Your caliper is now in perfect
position and ready to be tightened. You’ll back the pads off again in a few moments.
D. Tighten the two CPS bolts that attach the caliper to the mounting bracket. Tighten
one and then the other, repeating until they are at the specified torque.

If you follow these (and obviously the remainder of the instructions for the BB7) you'll get good alignment, even without facing your frame's mounts.
 

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Do what he posted and if your rotors are straight and you have the right adapters there should be no problems. Sometimes though, you do get warped rotors out the box, but I've nevr seen any that would rub both side with the pads adjusted all the way out.

Team Fubar Rider said:
I don't want to sound like I'm asking a stupid question, but have you followed the Avid installation instructions? Here is what they say as far as aligning the caliper (to which I've paraphrased a bit).

A. Make sure the CPS bolts are loose. (The CPS bolts are the bolts that attach the caliper to the mounting bracket.)
B. Turn the inboard (closest to the wheel) knob clockwise until it pushes the ro-
tor so it is in a position that is closer to the outboard side. Note that the rotor should not be centered between the walls of the caliper body. The spacing should be 1/3 on the outboard side, 2/3 on the inboard side.
C. Turn the outboard pad adjustment knob in until it is firmly squeezing the rotor against
the inboard pad - thus immobilizing the actuating arm. Your caliper is now in perfect
position and ready to be tightened. You'll back the pads off again in a few moments.
D. Tighten the two CPS bolts that attach the caliper to the mounting bracket. Tighten
one and then the other, repeating until they are at the specified torque.

If you follow these (and obviously the remainder of the instructions for the BB7) you'll get good alignment, even without facing your frame's mounts.
 

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Also you can do this: loosen the CPS bolts, Give the brake lever a squeeze and tighten the bolts then release the lever this should align the caliper perfectly!
 

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NO, it will not it will align the caliper since these are SINGLE PISTON brakes, so the side without a piston constantly rubs. If however you did this but before gave the inner pad a few turns in and then released it after it would, easier solution though (which as as I remember is part of the SRAM setup) is to tighten down the pads manually to the prescibe 1/3-2/3 ratio, tighten the CPS bolts and then back the pads off appropriately.

ae111black said:
Also you can do this: loosen the CPS bolts, Give the brake lever a squeeze and tighten the bolts then release the lever this should align the caliper perfectly!
 

· 2010 RockHopper Comp Disc
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You need to first take the calliper off and evaluate that the outboard piston has not been hyper extended, you can do this by pushing it in, If you turn out the outboard adjuster all the way, the silver piston should come very close to going inside the calliper. If it doesn't, then you need to push it in. If it wont go in then you need to disassemble the calliper and un hyper extend the piston. Not a very hard job.

Now that you have the calliper in good working order, put it on the mounts. Tighten down the cps bolts just enough, so you can move the calliper around. Now Turn out the inboard pad until you get a 1/3(outboard) and 2/3(inboard) separation, just like the instructions. Though you absolutely must make sure that your outboard piston does not become hyper-extended. I believe it comes hyper extended after 19-20 clicks, so keep it the outboard pad under 15 or so clicks. If you need to go over 15, then compensate with the inboard pad. Remember that as pads wear you will need to extend the outboard piston, so we don't want it to hyper extend in the future.

Before you tighten down the outboard pad, spin the wheel while the inboard pad is properly set. Keep spinning it and as you do so tighten the outboard pad 1 click at a time. Keep spinning the wheel until you tighten it down with the outboard pad. Now the rotor should be secure, but make sure you do not crank down on the knobs, just secure the rotor. Now tighten the cps bolts in a 1/4 of a turn increments until tight and secure.

Now click each pad out around 4-5 clicks and spin. If you hear rubbing turn out the outboard pad first, and if its not it then re tighten it and turn out the inboard pad until there is no rubbing. Though minor rubbing is ok.


I hope this helps. It took me about 5 installs to figure out this method and it works great for me.
 

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LyNx said:
NO, it will not it will align the caliper since these are SINGLE PISTON brakes, so the side without a piston constantly rubs. If however you did this but before gave the inner pad a few turns in and then released it after it would, easier solution though (which as as I remember is part of the SRAM setup) is to tighten down the pads manually to the prescibe 1/3-2/3 ratio, tighten the CPS bolts and then back the pads off appropriately.
funny it works on my bike as long as I adjust the inboard adjuster correctly a quick squeeze and it's perfect...... Awe nevermind!
 

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Prophet Julio said:
Or maybe the caliper is hitting the outside edge of the rotor. Do you have the right adapter for the rotor size? Is the adapter upside down? Is the rotor compatible with the bb7?
I've got this problem. Domain 302 with Maxle and 185mm Avid BB7. I put the whole wobbly pile of spacers BB7 comes with between caliper and post mount and still there's no room to put the front wheel on. The wheel just doesn't go in the fork because the caliper is too forward, hits the rotor and blocks the wheel. WTF?

160mm SLX with same wheel and fork was just throw it in and ride. So what am I doing wrong here with the BB7? :confused:

EDIT: Ok, I figured it out. I need an adapter. Damn. Back to 160 for now.
 
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