Avid SD7's won't tighten on the bosses
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Avid SD7's won't tighten on the bosses
I am trying to install a brand new set of Avid Single Digit 7 v-brakes on the rear of my Surly 1x1. The bike is 2 years old and has had an SD7 on it before (I cannibalized it to build a Karate Monkey, now I'm rebuilding the 1x1 and using a new rear brake).
I slide the the arms onto the bosses, making sure the pin is in the center hole, and tighten to the specified torque using a torque wrench, but both arms are still loose on the bosses. They rattle around and slide up the bosses at least half a millimeter.
I have lightly greased the bosses and the mounting bolt and I just can't figure out why I can't get these things tight.
Any ideas would be appreciated.
I slide the the arms onto the bosses, making sure the pin is in the center hole, and tighten to the specified torque using a torque wrench, but both arms are still loose on the bosses. They rattle around and slide up the bosses at least half a millimeter.
I have lightly greased the bosses and the mounting bolt and I just can't figure out why I can't get these things tight.
Any ideas would be appreciated.
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arent there supposed to be washers your using? Are you using them
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I've had this happen with a couple of frames. I just filed the boss shorter to remove most of the slop. On the bike I had, the bosses were threaded into the frame, so I wasn't worried about messing it up. Not sure what the surly is like though.
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Thanks for the responses, guys, but I'm still stumped. Yes, I'm using the supplied washers. And I tried adding an extra washer and that didn't change anything. After studying the situation it looks to me like the mounting holes for the brake arms are too long (deep). It's as if the arms are bottoming out on the little lip at the base of each boss too early, making it impossible to tighten the arms. It's almost like I'd need to make the bosses themselves a little longer.
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A washer should fix the problem. It should extend the brake outward so it will tighten. If not take some post off, but I don't see how it will help if the washers didn't. I have the same brakes and they are not perfectlly still on the posts. Half a millimeter is not much.