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Discussion Starter · #1 ·
Hello everyone, I recently got a new Surly Big Dummy. I have had it for a few days, done a few short miles on it and everything was working great. One day, I decide to put slime in the tubes and drill out the rims for schrader valves. It is getting late and dark, and I am in a hurry to get this project wrapped up.

Getting it all put back together and what do you know, I put the front wheel in backwards(unknowingly), with the disc on the opposite side of the caliper. I clamp down the wheel skewer, and grab the wheel to give her a spin, just to test everything. I try to spin the wheel and it does not spin. I try again, both times with a decent amount of force. I am confused, then I realize they do not spin because the wheel is on backwards, and the dish is causing the spokes to hit the BB7 brakes.

My question is, would that be enough force to bend the caliper mounting bracket that is welded onto the fork? Ever since this event occurred, it seems I cannot get the BB7's outer pad(& mounting hardware!!! ) to stop rubbing, even in the most backed out position.

Also, if it is bent, how to bend it back? Or is new fork the answer?

I know, I know. Let the flaming begin, embarrassing situation, and I would think of my self as a decent bike mechanic any other day.
 

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Is there not enough caliper-sliding room to re-align with the rotor?

I think if anything bent it might be the adapter, not the fork mounts, but I doubt it did. You probably did not put as much force on it as if you were braking hard.

-F
 

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Most unlikely that you did any actual damage.

If backing out the pads doesn't stop rubbing, loosen the bolts that tighten the caliper to the adapter, align the rotor around the center (a bit biased towards the inner pad) and everything should work out fine.
 

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Discussion Starter · #9 ·
Most unlikely that you did any actual damage.

If backing out the pads doesn't stop rubbing, loosen the bolts that tighten the caliper to the adapter, align the rotor around the center (a bit biased towards the inner pad) and everything should work out fine.


What if I have both pads backed all the way out, and the bolts that tighten the caliper to the adapter loose, and there is no side-to-side play(like I know there should be) because the rotor is still hitting the outer pad, and the adapter, and the conical alignment washers? I know this shouldn't be, there should be side to side movement to be able to align the caliper properly, like you are explaining. If I tighten down the caliper mounting bolts, pulling the caliper all the way out to help ease the problem and center the rotor, there is still no hope in centering it between the pads. It is still touching the outer pad and conical washers.

It sounds like I am not strong enough to bend the welded bracket, and that sounds right. Maybe the welded bracket has been a little off the whole time? Maybe one of the dropouts is slightly off? Can quality control on frames/forks be a little out of line sometimes? The only other thing I can think of is spacers on the axle/hub, but they are brand new wheels that came with the bike, and everything wheel wise seems correct to me. Maybe I am missing something else. Also, I have set up multiple BB7s before on multiple bikes, so its not my first time around the block, although I sometimes question that as I put the wheel in backwards the other day.:madman:
 

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Discussion Starter · #10 ·
I also double checked the rotor being screwed onto hub correctly, and everything is fine there as well
 

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When the caliper was pressed against the spokes with the wheel flipped, it would have moved outwards (if it was bent at that point). This would cause the rotor to rub against the inner pad, not the outer pad and conical washers.

The rotor probably didn't touch anything on the opposite side so it should be fine. Doesn't hurt to check but I would look elsewhere.

To isolate the problem, begin installation of the brake caliper from zero: mount the adapter on the fork and mount the wheel. How does it look? The rotor should be close to the adapter with a couple millimeters (rotor thickness) of clearance. You should see at this point if the hardware is bent.

If it is bent, you can bend the mounting tabs on the fork with an adjustable wrench or face them with a flat file, doing both at the same time with one stroke.

Once the adapter looks right next to the rotor, it's time to mount the caliper. The rotor should no longer rub the conical washers and you should be able to center the rotor.
 

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If you bent anything, it was a spoke. The caliper & associated mounting hardware was designed to take more force than you can put on it with your hand.

I say this next part not to lecture, but because it took me FOREVER to learn: When something's going wrong during a repair, NEVER try to force it. Slow down, look for the problem & use your brain to figure out a solution.

Can't tell you how much time/money I could have saved by following that advice sooner LOL.
 

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I know it falls in line with a computer tech asking you to check to make sure it is plugged in first..... but are you sure the wheel is seated in the dropouts correctly? I know I have slipped a wheel in quickly, not paying attention, and had it caught at an angle in the dropout. First sign of problem was the brakes rubbing badly. Checked all sorts of things before thinking of the most obvious thing, the wheel was not set correctly. Just figured it wouldn't hurt to check.
 

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I can't picture in my head how exactly the OP mounted the wheel backwards. :confused: Please post a pic...it may help a beginner like me avoid similar scenario.
 

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I can't picture in my head how exactly the OP mounted the wheel backwards. :confused: Please post a pic...it may help a beginner like me avoid similar scenario.
Pull wheel off of bike (out of dropouts), turn wheel 180 degrees so brake rotor is on the opposite side, put wheel back into dropouts.
 

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Omg...

Hello everyone, I recently got a new Surly Big Dummy. I have had it for a few days, done a few short miles on it and everything was working great. One day, I decide to put slime in the tubes and drill out the rims for schrader valves. It is getting late and dark, and I am in a hurry to get this project wrapped up.

Getting it all put back together and what do you know, I put the front wheel in backwards(unknowingly), with the disc on the opposite side of the caliper. I clamp down the wheel skewer, and grab the wheel to give her a spin, just to test everything. I try to spin the wheel and it does not spin. I try again, both times with a decent amount of force. I am confused, then I realize they do not spin because the wheel is on backwards, and the dish is causing the spokes to hit the BB7 brakes.

My question is, would that be enough force to bend the caliper mounting bracket that is welded onto the fork? Ever since this event occurred, it seems I cannot get the BB7's outer pad(& mounting hardware!!! ) to stop rubbing, even in the most backed out position.

Also, if it is bent, how to bend it back? Or is new fork the answer?

I know, I know. Let the flaming begin, embarrassing situation, and I would think of my self as a decent bike mechanic any other day.
another "somebody hide their tools..." :shocked: :eekster: :eek:ut:
 
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