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harlond
01-27-2019, 09:53 AM
I'm working on a 1986 Specialized Rockhopper frame. Looking at the rear cantilever brake posts, it is apparent that the non-drive side post is not parallel to the drive-side post, but instead is canted slightly outward. I acquired the frame only recently and don't know it's history. But it is obvious from the condition of the frame that it was ridden plenty, so presumably the brakes worked OK, and I suppose any lack of parallelism was addressed by toeing in the brake shoes on the non-drive side.

Is there any reason I should make an attempt to bend the brake post toward a more parallel alignment? And if the answer is yes, how would I do that? The post isn't very long, and there doesn't look to be much scope for bending in the post. (FYI, I've already cold set the rear drop outs to 135mm.)

BTW, the seat post lower bottle cage mount is installed so that it points slightly to the right rather than straight ahead. Doesn't look to me like it would prevent installation of a bottle cage, and I assume the frame was just built that way. Which is what I assume about the brake post, too, but I could be wrong. (I recall reading the very early Rockhoppers were built by Giant, not sure that bears on the issue one way or another, just saying.)

Thanks.

Hindmost
01-27-2019, 10:37 AM
I can't imagine that trying to cold set a cantilever post would end well. As you say, the cantilever/v brake has a lot of adjustability. Whereas, many metal bottle cages can be tweaked into line when installed.

unterhausen
01-27-2019, 10:59 AM
I have never seen a canti post that can be cold set satisfactorily, and many will come apart because the boss is just swaged to the base. It's not a great situation, but the brakes will work okay. It's harder to keep them from squealing when the posts are catywumpus.

pbarry
01-27-2019, 11:04 AM
Do you have the one piece boss/post or the female boss with the post threaded into it?

harlond
01-27-2019, 11:12 AM
Do you have the one piece boss/post or the female boss with the post threaded into it?One piece, thanks.