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  1. #1
    J&L
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    Rear hydraulic brakes seems softer than front?

    Just got a new tandem with identical Hope hydraulic brakes, front and back. The rear brake lever has always been softer and has more travel than the front. Thought it could be air in the system, so I tried bleeding the system. But the difference still remains.

    Have others experienced this difference?

  2. #2
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    I've noticed this on our brakes too. (Magura's and then Hopes)

    I pressume that it's the extra length of the hose that causes it.

  3. #3
    PMK
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    Already mentioned was the hose. It could also be the brakes needing to bed in some, but overall rears are often softer feeling than fronts.

    FWIW, even though fluids are considered non compressible, they will compress. I have not yet needed to accomplish this on a bicycle, but would if a quality hose and good bleed left things soft.

    Prior to pressure bleeding with a syringe or brake bleeder, put the fluid in a clean glass bottle that can seal well. You must use glass so the sidewalls do not collapse and you can see the emulsified bubbles float out.

    Ensure the cap will seal under vacuum, and somehow adapt the cap to you syringe or better still, purchase a MightyVac brake bleeder kit. With more than enough fluid in the bottle, apply and hold a vacuum on the fluid. With proper vacuum, emulsified bubbles will make the fluid cloudy. Once the fluid clears while positioned under vacuum, slowly release the vacuum.

    With care fill your syringe or brake bleeder. Bleed from the bottom up.

    Just a thought, chances are it's the hose expending slightly.

    PK

  4. #4
    J&L
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    Thanks for the input.
    One day I might go the full MightyVac route, but it sounds like they are behaving as expected.

  5. #5
    Professional Crastinator
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    Do all of you run braided stainless hose on your tandem hydros?

    Thanks,
    -F

  6. #6
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    Yep braided hoses here.

  7. #7
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    Quote Originally Posted by PMK
    FWIW, even though fluids are considered non compressible, they will compress.
    Not at the pressure exerted in the this system! It takes a LOT of pressure to compress a liquid.

    Its your brake hose expanding or you have air in the system.

  8. #8
    Down South Yooper
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    I'm running Magura Louise's on my dummy, with a tandem length rear. I had to bleed it several times to get it up to par, but it feels identical to the front. I think I trimmed 3-4" off the 2500mm hose (nothing like mixing units), so the hose is pretty much as long as possible..

    I ended up taking the brake off the bike to bleed it, my arms weren't long enough to do it on the frame, too long from end to end to manage the filling/syringing. Went much easier off the bike. Might give that a try.

    Plum
    This post is in 3B, three beers and it looks good eh!

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