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Old 10-26-11, 03:05 PM   #1
StrykerIV
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Tektro 720R - Installed Wrong?

I installed a new Tektro 720R on my girlfriends bike, but something doesn't seem right.

Did I install this incorrectly? Is there something wrong with the brake? Would tensioning the brake or correcting the toe-in fix it? (as you can see, the right brake pad is secured tightly and since the arm is bent outwards, no matter how I adjust the brake pad, it too bends outwards).

Any suggestions?
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Old 10-26-11, 03:33 PM   #2
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Stryker: You could start by closing the quick release lever, the black lever on the side should point down. Then follow this guide http://www.parktool.com/blog/repair-...-brake-service
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Old 10-26-11, 03:54 PM   #3
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You have the entire caliper cocked over toward the left side. Rotate the entire thing clockwise to center the arms.
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Old 10-26-11, 04:51 PM   #4
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the spherical washer should take care of the pad alignment. along with centering the caliper as noted above
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Old 10-27-11, 07:14 AM   #5
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Quote:
Originally Posted by dsbrantjr View Post
Stryker: You could start by closing the quick release lever, the black lever on the side should point down. Then follow this guide http://www.parktool.com/blog/repair-...-brake-service
The quick release would not close because of the angle of the left brake-pad arm. I even loosened the brake pad so that it would "give" as much as possible.

As for the entire caliper cocked over the to the left, it was not. It was installed perfectly straight. Even after taking the caliper off of the bike and looking square at it, both arms were twisted to the left. I had two pro bike mechanics try to install it and they both said it was bent. I've since installed a new caliper without any problems, so I know my fork isn't broken.


As for the spherical washer, it SHOULD take care of the pad alignment, however with the brake-pad arm twisted out so far, there was no way to angle it any further (closer to the bike in the front), let alone toe it in.
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Old 10-27-11, 07:32 AM   #6
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This is supposedly the same caliper installed on a different bike at the merchants store. Notice how the two arms are parallel to one another in this picture. Notice in my picture the two arms are nowhere near parallel.
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Old 10-27-11, 09:03 AM   #7
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If you're saying you think the brake arm opposite from the QR is bent, then I'd agree. Looks bent to me. If you try to angle the shoe to where it should be (If you can) that might work. I'd think the only course you have is to remove the shoe and the wheel and take a big wrench and twist that arm till its back straight again. If you do, I hope it wont brake something. Replacement would be the only other way to fix it. I'm only an amateur shadetree doityourselfer, so I defer to any other advice out there.
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Old 10-27-11, 09:41 AM   #8
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Just had a closer look at your photo. Looks like the brake arm has a twist in it.
If it's new, a replacement from your supplier is in order.
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Old 10-27-11, 11:25 AM   #9
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I don't know what kind of bike that is, but that fork looks to me more like a cyclocross fork. Do they make unicrown forks for road bikes with short reach calipers? The Tektro R720 is a short reach caliper, so maybe it's just incompatible?

Maybe you were looking for the CR720 and got the R720 by mistake?

CR720:
http://tektro.com/_english/01_produc...e&sort=1&fid=2

R720:
http://www.amazon.com/Tektro-R720-Ca.../dp/B0010366KY

Last edited by Metaluna; 10-27-11 at 11:32 AM.
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