Spoke lacing on a Rohloff

Discussion in 'Cycling Equipment' started by Dan Burkhart, Dec 27, 2004.

  1. Dan Burkhart

    Dan Burkhart New Member

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    Hello all. Hope Santa was good to everyone. I just finished building a Speedhub into a 26" Mavic X517, and contrary to Rohloff's insistence that 26" wheels must be built 2 cross, I made it 3 cross using 256mm spokes, and it looks ok to me. The nipples come out of the rim at a slightly greater than normal angle, but not as severely as a 4 cross 36 spoke wheel I have with a Sachs 7 speed hub.
    Just wondering if anyone else here has built them 3 cross and how they held up over time.
    Thanks
    Dan
     
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  2. Per Dan Burkhart:
    >Just wondering if anyone else here has built them 3 cross and how they
    >held up over time.


    Haven't tried 3x, but how much do you weigh?

    I'm about 220# and have toasted 3 517's laced 2x on the rear....so now I use
    something stronger in the rear.
    --
    PeteCresswell
     
  3. Tom Ace

    Tom Ace Guest

    Dan Burkhart wrote:

    > Hello all. Hope Santa was good to everyone. I just finished building

    a
    > Speedhub into a 26" Mavic X517, and contrary to Rohloff's insistence
    > that 26" wheels must be built 2 cross, I made it 3 cross using 256mm
    > spokes, and it looks ok to me. The nipples come out of the rim at a
    > slightly greater than normal angle, but not as severely as a 4 cross

    36
    > spoke wheel I have with a Sachs 7 speed hub.


    What was your goal in lacing 3X?

    2X on a Speedhub already has a lever arm larger than you
    get with tangential lacing on a typical large-flange hub.
    That is, Rohloff 2X is already overkill for torsional
    stiffness. 3X just makes the angle at the rim worse,
    without any significant benefit that I can think of.


    Tom Ace
     
  4. Dan Burkhart

    Dan Burkhart New Member

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    I weigh about 245, and I have been riding this bike for 5 years on the original Mavic 223s with nary a broken spoke or a tacoed wheel, so I thought the 517 would work ok. After hearing about your experience though, I guess I better keep an eye on it.
    Dan
     
  5. Dan Burkhart

    Dan Burkhart New Member

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    Yeah, I realize all that now. It was just my thick headedness thinking that what Rohloff really meant was that 2 cross was the minimum, so I went ahead and ordered the spokes for 3 cross. So not wanting to waste perfectly good double butted spokes that are probably a length not useable for any other application, I went ahead and built it.
    Dan
     
  6. Per Dan Burkhart:
    >I weigh about 245, and I have been riding this bike for 5 years on the
    >original Mavic 223s with nary a broken spoke or a tacoed wheel, so I
    >thought the 517 would work ok. After hearing about your experience
    >though, I guess I better keep an eye on it.


    245? Is this for road or MTB? If MTB and I could, I'd unlace that puppy right
    now and return it....cut your losses while you can.
    --
    PeteCresswell
     
  7. Dan Burkhart

    Dan Burkhart New Member

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    It's for MTB. I'll take it under advisement, thanks. I had no idea the X517 was such a dud.
    Dan
     
  8. daveornee

    daveornee New Member

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    It's not a dud, but it is light weight and intended for rider + load (not bicycle, but water, tools, etc.) of 90 kg or less.

    A 3 cross build from a Rolhoff hub won't help and it might make it tougher on the spokes.

    F519 or XM 719 are rated at 115 kg.
    D521 is got to be rated @ 125 kg or more, but it isn't listed any more with Mavic's technical site.

    Have you considered Velocity Synergy rim?
     
  9. Chalo

    Chalo Guest

    (Pete Cresswell) wrote:
    > Per Dan Burkhart:
    > >Just wondering if anyone else here has built them 3 cross and how

    they
    > >held up over time.

    >
    > Haven't tried 3x, but how much do you weigh?
    >
    > I'm about 220# and have toasted 3 517's laced 2x on the rear....so

    now I use
    > something stronger in the rear.


    At 350+ pounds, I felt that I needed something stronger than *any*
    32-spoke wheel. (Rohloff claim that their hub makes a wheel that is as
    strong as a 48-spoke rear wheel because it is dishless. I don't know
    what measure of wheel strength they use to justify that claim. I
    wanted 48 spokes anyway.)

    So I set about adding some extra holes to the hub shell-- 8 extra on
    the left and 16 extra on the right-- and laced up a 48-spoke wheel in a
    crow's foot pattern:

    http://img140.exs.cx/img140/328/bohmdriv6fo.jpg

    That's 32 cross-2 spokes plus 16 radial ones, attached to a 750g Snow
    Cat rim.

    I used a 2.5 axis CNC mill to drill the hole pattern. I made a special
    fixture plate to securely hold the opposite flange without marring it.
    Thus I did not have to disassemble the hub for the machining operation.


    I filled the 8 unused spoke holes with tiny screws, to make it easier
    to keep track of the lacing pattern. The spokes worked out to be
    unusal sizes-- 240mm and 220mm long-- so I had to have them cut to
    order.

    Drilling into a hub that expensive was an uneasy operation, but it all
    went according to plan. I am confident that my hole pattern is held to
    tighter tolerances than the original drilling.

    Chalo Colina
     
  10. gearoidmuar

    gearoidmuar Guest

    3 cross should be fine.
    Radial spoking can cause problems if hub not strong enough to withstand
    straight pull. The more oblique the pull, the more metal there is to resist.
     
  11. daveornee

    daveornee New Member

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    When I said 3 cross could be harder on the spokes with this hub, I meant the rim/nipple end of the spokes. With such a large diameter flange the spoke angle at the nipple can be a problem. It is dependent on the nipple angle and how the rim socket/eyelet/interface deals with the angles and stresses involved.
    If you will notice, Chalo's build didn't go to 3 cross, but it did include some radial spokes.
    I suggest the OP take a look at the angles of the spoke departure from the nipples.
     
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