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  • Our ROADHOG forks caused a bit of a stir when they were released to
    compliment our ROADRAT frame. Why? Well, as you can see from the
    photo, the disc mount is positioned on the front right of the fork
    rather than the more usual left rear. As always with Cotic products,
    there were firm engineering reasons for Our ROADHOG forks caused a bit
    of a stir when they were released to compliment our ROADRAT frame.
    Why? Well, as you can see from the photo, the disc mount is positioned
    on the front right of the fork rather than the more usual left rear.
    As always with Cotic products, there were firm engineering reasons for
    placing it where it is, and here's the lowdown:

    Forces Axle movement under disc braking is now a fairly well known
    phenomenon in mountain biking. Basically with the caliper positioned
    left rear (usual place), and a vertical dropout, there is a reaction
    of the braking force which tends to push the axle out of the dropout,
    hence you're relying on the friction of your QR to counteract this
    rather than a completely mechanical stop. Most manufacturers have
    moved to a slightly forward facing dropout to counteract this.

    We've actually never experienced any trouble with this on our mountain
    bikes, but during prototype testing of the ROADHOG fork - which had
    the disc mount in the usual left rear position - we did actually
    experience some axle movement. Nothing actually came undone, but after
    some serious downhill braking on fast roads, the rotors would be
    rubbing a touch and the wheel would 'clunk' home in the dropout when
    we undid the axle nuts. This was clearly unacceptable, so we set about
    finding a solution. Our first port of call was forward facing
    dropouts, but these would have required custom cut version which would
    have increased the fork cost disproportionately. Therefore the design
    problem became how to contain the disc forces whilst using an off the
    shelf vertical dropout. The solution, as you can see, was to place the
    disc mounting on the front. This puts all the forces into the dropout,
    and is still a completely normal International Standard setup, so it
    takes any IS caliper. It also gets the brake away from the back of the
    fork which brings us to.... it where it is, and here's the lowdown:

    Forces Axle movement under disc braking is now a fairly well known
    phenomenon in mountain biking. Basically with the caliper positioned
    left rear (usual place), and a vertical dropout, there is a reaction
    of the braking force which tends to push the axle out of the dropout,
    hence you're relying on the friction of your QR to counteract this
    rather than a completely mechanical stop. Most manufacturers have
    moved to a slightly forward facing dropout to counteract this.

    We've actually never experienced any trouble with this on our mountain
    bikes, but during prototype testing of the ROADHOG fork - which had
    the disc mount in the usual left rear position - we did actually
    experience some axle movement. Nothing actually came undone, but after
    some serious downhill braking on fast roads, the rotors would be
    rubbing a touch and the wheel would 'clunk' home in the dropout when
    we undid the axle nuts. This was clearly unacceptable, so we set about
    finding a solution. Our first port of call was forward facing
    dropouts, but these would have required custom cut version which would
    have increased the fork cost disproportionately. Therefore the design
    problem became how to contain the disc forces whilst using an off the
    shelf vertical dropout. The solution, as you can see, was to place the
    disc mounting on the front. This puts all the forces into the dropout,
    and is still a completely normal International Standard setup, so it
    takes any IS caliper. It also gets the brake away from the back of the
    fork which brings us to....

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