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Thread: Modify a fork

  1. #1
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    Modify a fork

    I have a fork that I would like to have modified. I would like to increase the rake from 50 mm to about 58 mm and move the brake bosses. The guy who built it for me years ago has retired. The guy who modified another fork for me is too busy. Another guy whose name I was given sent me a snooty e-mail implying if I wanted to modify a fork I was an idiot.

    Anyone have any ideas?

  2. #2
    Senior Member ftwelder's Avatar
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    Few frame builders also build forks. Of those who do, only a fraction rake the fork after building and would have tooling to rake a built fork. Of those who can rake built forks, even fewer are able to modify an existing fork without altering their existing tooling.

    I think the cost of modifying your fork may either exceed the value of the fork or render it useless due to a failure of some type during the modification process.
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  3. #3
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    Google "fork bending mandrel". There are a lot of ideas for wood forms you could use to do it yourself. In the end, if you mess it up you will be in the same situation you are in now, wanting a new fork. Reynolds is the only company I've found that sells a pre-bent blade so it's safe to assume that all of those curved blades on hand built bikes out there were bent by the builder. It's just a question of how much effort to put into this fork before it's easier to wait for the builder you talked to.

  4. #4
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    You can bend your own fork blades by bending each blade one at a time, and this appears to be the main method. The right way to adjust the fork is with the kind of bender than bends both blades at a time, which is pretty unusual in the average shop. People do stuff like shove both blades under a door. The good news is that 8 mm isn't that much. And it is possible to bend the blades in sequence, but then it becomes essential to have a controlled method, and to have excellet measurement devices.

    There are folks doing the bending, a pall of mine who lives over the border in NY, NY got someone to do him a fork, I have no idea whom, but it is out there. Conceptually custom builders should be doing custom front end geometry, and it takes the ability to get the forks right to do that. I have thought of doing it by kerfing the top of the fork, and then welding the kerf shut.

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