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  1. #1
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    Why do most hydraulics have a long lever throw?

    I've been on dozens of hydraulics and they all have the same character trait: it takes a good 2 cm of pull before the brakes are really effective. I could set up V's so that with 3-4mm of pull, they'd have action. I like 'em really tight and although all the brakes work fine, it's just not how I like them to engage. A lot of people call this 'good modulation'. What I'm asking is how can hydraulics be adjusted so there isn't as much modulation? (if you've noticed that Hayes Stroker ad that pops up above - that's what I mean and that's WAY too much lever action for me).

    PS - I know it's a personal preference thing and most propably prefer a longer lever pull. But, they should make hydros adjustable for those of us who don't.
    Last edited by Uphiller1; 10-15-2008 at 06:36 AM.

  2. #2
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    [SIZE=2]Most brakes can be bled so they have less lever movement before they engage like Hope, Avid etc. Some like the latest Shimano XT’s have Free Stroke which allows you to adjust the point at which your brakes engage though I found that feature to be almost useless, other brakes have the same feature that actually has an effect though like the latest Hope brakes which I had a fiddle with last week. Some people put little shims on the back of the brake pads to ensure they engage quicker or move the pisons out a bit though that will obviously take away some pad clearance. I’ve got the Stroker’s and there is quite a lot of lever throw before they engage but like you say, it comes down to personal preference, I like it how it is but you may like the relatively quick engagement of Hope brakes.
    [/SIZE]
    Last edited by EGF168; 10-15-2008 at 09:41 AM.

  3. #3
    Meh.
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    You can just remove the wheel and pump out the pistons a little bit.

    You can purposely overfill the system.

  4. #4
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    its nice to have more throw so you can ride with your fingers on or partially engaging lever and not have the slightest bump move your fingers

    mx

  5. #5
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    i have 08xt's and they have a reach of aprox a 5mm before coming n contact and within another 5mm they are at full tilt.

  6. #6
    dru
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    In answer to the OP, the hydraulic reason there is a fair amount of movement in the lever is the fact that the master cylinder piston has a very small diameter. Your hand generates some amount of force on the small surface area of the mc piston, but moves the piston fairly far in its bore.The caliper pistons are quite large by comparison, and have a large surface area, so a huge amount of force is generated but very little movement.

    Other factors that can cause excessive lever travel are air in the system, spongy lines, flex in the caliper, or brake lever/MC, poor design from the manufacturer, sticky pistons, and warped rotors. The length of the lines matters too, my front brake lever has a much more solid feel than the rear one.

    Drew

  7. #7
    trail addict
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    Quote Originally Posted by Uphiller1
    A lot of people call this 'good modulation'.
    Modulation means more force at the lever translating into more braking force. "Good Modulation" means the brakes don't have an on/off feel to them-you can control them precisely with attention to your lever pressure.
    You better just go ahead and drop that seatpost down to the reflector... the trail gets pretty rough down there.

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