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  1. #1
    Senior Member CanadianBiker32's Avatar
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    Front Disc Brake Alignment questions

    Ok i have mt bike. Disc brakes that are hydraulic, front disc - rotor often goes out of warp.

    Any tools that i can find or use that help to align the rotor properly? instead of just looking at the gaps in the brake pads etc?

    otherwise what is the secret to getting these stupid rotors to work straight? thanks!

  2. #2
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    If then rotor has a solid, uninterrupted circular track, then you can mount an indicator to the fork with something like this (search for flexible indicator mount). Before you buy, make sure you have the clear track, because any hole or slot will make the indicator hop. Or you can simply hole a dry marker steady against the fork or caliper, and use it to marik high spots as you rotate the wheel.

    Either way, you'll bend the disc by brute force, using an adjustable wrench closed down to a narrow slot.

    As to why it warps, possibly the caliper is too far off center, or possibly you're overheating the disc from excessive use of the front brake, or possibly the disc is prone to warping either because of design, or because or residual stress which returns it to (warped) shape when warm enough.

    If you successfully straighten it, and the caliper is centered, and it warps fresh, you might try a new rotor.
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  3. #3
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    Quote Originally Posted by CanadianBiker32 View Post
    front disc - rotor often goes out of warp.
    Some lightweight rotors just can't stay true, knowing details of what you have helps.

    If it won't stay straight, would look at replacing with a Shimano or other sightly heavier weight that holds it's trueness better.

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