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Increase the efficiency of brakes in an ATV?

  1. May 10, 2008 #1
    how can we increase the efficiency of brakes in an ATV specially?

    I'm working on an ATV these days n plan to use disc brakes....
    i read about cross-linked braking circuit.....can someone tell me how efficient is this system....should i try to employ it?iv heard it has been used in Audi before.....can someone elaborate on its advantages and disadvantages?
     
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  3. May 10, 2008 #2

    Danger

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    I'm not sure what you mean by 'cross-linked' braking. My Roadrunner has 'dual diagonal' braking, which might be the same thing. The master cylinder has 2 outlets. One goes to the left front and right rear wheel. The other takes care of front right and rear left. The idea is to keep the car straight if one of the subsystems fails.
     
  4. May 10, 2008 #3

    mgb_phys

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    What about an anchor?
    ATC = cross country on soft ground = anchor + strong chain + firm attachment to chassis.
     
  5. May 12, 2008 #4
    @danger
    ya dual diagonal is the same as cross linked...does it help in turning or any such advantage?
    as in i am talking about torque effects if u have any idea?
    your roadrunner manual might have details about the system.......
     
  6. May 12, 2008 #5

    Mech_Engineer

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    What exactly are you trying to accomplish with the brakes? "Increasing the efficiency of the brakes" doesn't tell us what your design intentions are.
     
  7. May 12, 2008 #6

    Danger

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    The diagonal system has no effect upon turning or brake efficiency. All it does is minimize complications in the event of a system failure such as a ruptured hose. How it works is that the master cylinder has 2 chambers (you can think of it as 2 separate cylinders, but they run from the same push-rod). One is plumbed to the front left and the back right, the other to the front right and back left. Since the fronts are discs and the rears are drums, there's also a proportioning valve in each circuit. The set-up keeps the car stopping in a straight line, and with proper weight transfer, if something goes wrong. You can't even tell that it's there under normal conditions.
     
  8. May 13, 2008 #7
    most of the more modern systems use 2 lines to each front brake
    and a single line to each rear
    as the fronts stop much better then the rears due to weight transfer

    and drum rears are fast being dropped and all disk systems being used
     
  9. May 13, 2008 #8

    Mech_Engineer

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    Most modern cars have 4-wheel ABS, which means they have individual brake lines to each wheel. Some stripped-down pickup trucks or cars may still have a single brake line to the rear wheels, but they are becoming increasingly rare.
     
  10. May 13, 2008 #9
    What type of atv, like a buggy/sand rail or individual four wheeler ? What are you trying to accomplish with braking? what type of terrian will it be used on?
    I would use disc brakes front and rear. It wouldn't hurt to use a cross link system.
    You could also install cutting brakes(turning brakes).
     
  11. May 13, 2008 #10

    Danger

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    Yeah, I was wondering if the OP was thinking of cutting brakes when he asked about an improvement of turning. That's a whole different critter.
     
  12. May 17, 2008 #11
    its a Baja....4 wheeler....sandy n mountainous terrains...
     
  13. May 17, 2008 #12

    Danger

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    In that case, I'd want a separate brake circuit for each wheel. Unfortunately, human physiology, with its limited number of appendages, would make that difficult to control...
     
  14. May 17, 2008 #13
    we cant have more than 2 brake circuits so i am basically trying to find out what type of circuitry would best fit my case.....we are only using disc brakes....no drums....n max weight would be at d back because our engine and transmission systems are at the back....
    so i have to keep all that in mind too before deciding what kind of break circuit to use....
     
  15. May 17, 2008 #14

    Danger

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    I think that this comes down to a decision of which is more important to you, safety or versatility. For the latter, I would recommend using one circuit for both right wheels and another for the left. With separate controls for them, you can use them as cutting units (think of a bulldozer or tank turning). For maximum safety, the dual-diagonal system would be best. Keep in mind as well that as long as you're going forward, the front brakes are far more important than the rear ones. As soon as you start to decelerate, the weight transfer puts most of the force on the front wheels.
    RayB and Stingray both know a lot more about this stuff than I do, though, so they might have differing opinions. (What is it with cars and guys named Ray, anyhow?)
     
    Last edited: May 17, 2008
  16. May 19, 2008 #15

    Mech_Engineer

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    I personally would recommend a fairly standard brake setup- one "circuit" for the front brakes and one for the rears. It all depends on how a brake circuit is defined. Can one master cylinder with two outputs count as one circuit? What about a single output master cylinder with a T in the line after it?

    I'm not sure I see a definite advantage in using a cross-linked system in an off-road vehicle that will have limited traction anyway...
     
  17. May 19, 2008 #16

    Danger

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    Good points, Mech. I define a brake 'circuit' as being a fluid system that is not affected by leakage in any other system. That was the whole point of the dual-diagonal system in the first place. Since the 2 are completely separate (other than the actuator rod), a blown hose or cylinder in one half doesn't cripple the other half.
     
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