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  1. #1
    Slow But Still Pedaling
    Reputation: JimInSF's Avatar
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    Freewheel Spin, Chain Tension/Sag and Measuring Drag

    Hi all, I got my new Rohloff bike this week (pics to follow) and it seems a little draggier than when I first test rode it. This could be because my first real ride on it was in 20mph winds though, and could also be because when I tensioned the rear suspension, I ended up with pretty high chain tension.

    This got me to thinking - how much tension are folks running on their chains if you're not using a tensioner? How much sag do you get with one finger's light pressure?

    And how many times will your rear wheel rotate or how many seconds will it spin if you give it a spin with your hand holding the rear end up in the air? I know this is not a valid comparison to a derailleur setup, but just want to know how my new unit compares to other Rohloffs out there.

  2. #2
    mtbr member
    Reputation: Corporal Punishment's Avatar
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    I own an alfine hub (no rohloff experience). When I first got the hub, there was quite a bit of drag. After a few rides that went away. There are a lot more parts and pieces inside these hubs than a simple freewheel. Give it some time to break in.

  3. #3
    1*14*29*2.1 & 1*1*29*2.4
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    not sure of how many turns, but it will visibly slow down reasonalbly soon. It's due to the oil seal I think. some is due to the crank wanting to spin a bit. If you have over tightened your chain thenthat could contribute too. Just use it like any other drive train. I think no less than 1cm deflection should be about right. Mine gets quite loose after a bit of wear and it's no big deal to have it a little floppy as it never comes off. Also remeber you'll likely get tight spots from out of roundness of your chain ring. best to set it with 1cm deflection at that tight spot.

  4. #4
    mtbr member
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    The Speedhub has a 1000km break-in time. If you have just got the hub, then this excess drag is probably due to the hubs age. The hub also needs some time for the oil within it to get through the bearings and lubricate both these and the seals. Dry seals cause an enormous amount of extr afriction.

    Also try hitting the axle with a hammer as they recommend.The hub uses a free-floating bearing on the sprocket side and if this gets slightly out of line then drag is also increased.

  5. #5
    Slow But Still Pedaling
    Reputation: JimInSF's Avatar
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    Hit the axle with a hammer? This is a scary prospect, any pointers to details would be much appreciated.

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  7. #7
    Slow But Still Pedaling
    Reputation: JimInSF's Avatar
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    Much obliged!

    After loosening the chain a bit by moving the chainstays inward, it smoothened out and quieted down noticeably, it's only got a bit over a hundred miles on it so I'll give it a thousand to break in - hopefully by the end of the summer.

  8. #8
    Music & Bikes
    Reputation: fokof's Avatar
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    FYI

    Mine has about 10K on it and it still drags a bit in some particular speeds.

    It also shifts a lot better than when new
    "There is a big difference between kneeling down and bending over" -FZ

  9. #9
    Slow But Still Pedaling
    Reputation: JimInSF's Avatar
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    Yeah, I've got another one with 10k+ miles on it and this one actually seems better new than the older one!

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