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  1. #1
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    Reputation: krolik's Avatar
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    How much 'torque' does the Speedhub generate?

    Hi all. I am currently installing a Speedhub into a Nomad. I am making a diy speedbone based on a hope adapter but - in the meanwhile - I was thinking: is this force on the axle realy such an issue? I mean I know the axle tries to rotate, but is this seriously a problem?
    Any ideas?

  2. #2
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    Id put it like this....Shimano/Sachs/sram etc hubs can make do with toothed washers or a small arm. The Speedhub arm is ridiculously long for a reason. It needs the extra leverage to reduce this torque. I would guess that the cost and ugliness of this arm are things that any manufacturer would like to get rid of, there must therefore be a reason for it.

    I do also remember seeing a few pictures of the internet where a fork end dropout has opened up due to the wrong torque plate being used.

  3. #3
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    Reputation: Speedub.Nate's Avatar
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    Here's your answer, from the Rohloff users manual. It's a significant amount of torque, and because the Speedbone is so short, it's a highly concentrated force acting on the frame in the lower gears.

    Using the torque arm, which is a bit longer, diminishes this force, but it's still as though you were standing on the mid-point of your chainstay.

    speedub.nate
    MTBR Hiatus UFN

  4. #4
    emtb.pl
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    Thanks Nate, I have no idea how I skipped that info in the manual???
    I wonder how much torque on the axle does a standard hub generate. It does to some extend, right?

  5. #5
    emtb.pl
    Reputation: krolik's Avatar
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    Well, it seams the hub DOES generate a lot of force on the plate
    I had three hours to fit the speedhub and prepare the rig for a competition and the custom brake adapter didn't make it in time. So I just placed the oem2 plate in front of the adapter to make it safe in the soft gears and the external steering made it as the hard-gear protection.
    I was pretty sure there wouldn't be any movement but on fast parts of the course the hub did move (originaly placed safely for soft gears).
    Plus I had to run a 160 rotor in the back
    And an xtr rear der as a tensioner
    Anyway - a lot of fun and no issues whatsoever!
    The bike just received a e13LG1, a single pulley tensioner and a 203mm hope rotor.
    here's a pic from the competition. I will add pics of the bike later on.
    DSC0513012.jpg
    DSC05132.JPG

  6. #6
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    Reputation: Speedub.Nate's Avatar
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    Gotta do what it takes to put it on the trail. Good choice on the LG1 -- I run that on my wife's Speedhub setup and I like its flexibility. It's great on frames that don't work well with Rohloff's chain guide.

    After futzing around with our tandem's Speedhub setup, we took it for a short ride with only two axle plate bolts loosely fastened. It was pretty obviously jacked up when we finished. I'm grateful the scrawny bolts didn't shear and strand us.
    speedub.nate
    MTBR Hiatus UFN

  7. #7
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    Quote Originally Posted by krolik
    The bike just received a (...) single pulley tensioner
    I tried to use a single pulley tensioner on my horst link bike, and the chain would drop off VERY easily. I went back to dual pulley tensioner and have almost no problems. So I'd advice you to give the single pulley tensioner some rough testing before you go on long rides or use it in competitions.

  8. #8
    emtb.pl
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    I do give it a test for some time now.
    Good thing about vpp is that the chain gets SHORTER when sus compresses, so the only issue is when you rebound.
    About the force/torque - I had a go with a homebrew hayes 160 brake adapter - I just placed the OEM2 behind the adapter. The force indeed is impressive - it worked fine but when you went with harder gears it rotated in different direction and hit the swingarm - around 120deg rotation I use custommade hope 203 now (monkeybone design).
    This is what it looks like now:
    20090722(001).jpg

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