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  1. #1
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    650B and Mojo Owners

    Hey,

    Lets start a petition so Ibis will manufacture a longer swingarm to accept the 650B wheel with more clearance.

    David

  2. #2
    Mr.650b - Mr.27-5
    Reputation: Kirk Pacenti's Avatar
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    Quote Originally Posted by Mojo Man
    Hey,

    Lets start a petition so Ibis will manufacture a longer swingarm to accept the 650B wheel with more clearance.

    David
    Where do I sign?

    Cheers,

    KP
    “Those that say it can’t be done should get out of the way of those doing it.”

    Pacenti Cycle Design

  3. #3
    www.derbyrims.com
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    Enough prepaid orders might kick a 650b swingarm up the priority list. How much would you pay for a 650b Mojo swingarm? I'd imagine they would have to sell for over $500.

    The Pacenti 650b tires currently fit the Mojo. The Neo-moto is a tight fit and one of the two I've mounted so far needed aboput 10 or 15 irregularly taller knobs clipped a little shorter, and I'm getting more than the normal number of little rocks clicking the stays when mud sticks to the tire. Tape up your chain-stay yoke well and maintain it.

  4. #4
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    i'm in.

  5. #5
    Reviewer/Tester
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    I've been running both Pacenti tires on my Mojo without any problems. The Quasi fits and the Neo needs a bit of a "trim" but also fits.
    However, a 1/2" longer swingarm would be nice for muddy conditions and if Ibis produce one, i'll buy it immediately.


    R.
    It is inevitable ...

  6. #6
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    Way too vested in the bike not to jump in on this one.

    I'm in.

    Mario

  7. #7
    bike rider
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    1/2 inch longer swingarm is gonna handle differently, in my opinion not as well. Better option would be 1/4 inch longer BB-axle and differently shaped yoke area to get clearence.
    Keep the Country country.

  8. #8
    mtbr member
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    Quote Originally Posted by Lelandjt
    1/2 inch longer swingarm is gonna handle differently, in my opinion not as well. Better option would be 1/4 inch longer BB-axle and differently shaped yoke area to get clearence.

    the troll killer gets the "differently shaped yoke" part, but do tell; what the heck is a "1/4 inch longer "BB-axle"?

    felice navidad,

    tk
    Keeping the 650B forum hater free ever since 2008!

  9. #9
    bike rider
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    BB-axle distance is also known as chainstay length. In my experience bikes handle best with 16.25-16.5" chainstays. The Ibis is already a little long with 16.8". Go over 17" and you hurt climbing traction, manualling, and flickability. Traditionally the only bikes with chainstays over 17" were downhill bikes looking to add high-speed stability. The requisite long chainstays are considered one of the biggest drawbacks of 29" wheels that 650b tries to minimize.
    Keep the Country country.

  10. #10
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    Quote Originally Posted by Lelandjt
    BB-axle distance is also known as chainstay length. In my experience bikes handle best with 16.25-16.5" chainstays. The Ibis is already a little long with 16.8". Go over 17" and you hurt climbing traction, manualling, and flickability. Traditionally the only bikes with chainstays over 17" were downhill bikes looking to add high-speed stability. The requisite long chainstays are considered one of the biggest drawbacks of 29" wheels that 650b tries to minimize.
    I think those are good points. A slightly longer chainstay for the Mojo would slow handling a little at very low speeds, some riders might notice at first going from 650b with the original swingarm to a longer swingarm.

    But a slightly longer chainstay would reduce the stability loss due to the 1/2 inch higher BB and rider weight center going to 650b. For climbing a slightly longer chainstay would help keep the front wheel down with the higher BB. 17 1/4 inch chain stay should not feel sluggish handling with a 13.8 inch BB height and 5.75 inch travel suspension (the longer chainstay would increase travel the same amount).

    An option would be to keep the original swingarm and run the 650b tires smaller than 2.3 size, which do easily fit now with no reported clearance issues.

    With the Neo-Motos in the original Mojo swingarm the outside knobs do rub an XTR front der slightly when in the granny at top out (at sag they don't rub). This is another reason to lengthen the chain stay slightly for larger 650b tires.

    I don't have numbers at hand, but 29'ers with 4 inch or more travel have very near or over 18 inch chainstays.

  11. #11
    bike rider
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    Hadn't thought about the increase in BB height. I still think the shorter the chainstay length the better while providing clearance for bigger wheels. Since we're asking for a 650b specific swingarm it might as well be designed to not raise the BB.
    Keep the Country country.

  12. #12
    www.derbyrims.com
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    Quote Originally Posted by Lelandjt
    Since we're asking for a 650b specific swingarm it might as well be designed to not raise the BB.
    To maintain the same travel and frame angles except the BB moved lower to compensate for the higher 650b axle height then a whole new frame would have to be produced.

    It would be possible now to maintain the current BB height and frame angles, using a 1/2 inch shorter travel fork (130mm is close) and a custom shock with shortened i2i and stroke. Risse Racing Shocks could do it. Maybe PUSH and others could custom other brand shock lengths shorter also. The DW-Link action would probably still perform very well.

    Right now we who are experimenting with 650b on the Mojo just want a tad bit more clearance no matter how it's done. The higher BB height is not really noticeable except for far fewer pedal strikes. The BB-drop is unchanged, which is the primary basis for BB height stability. There's no noticeable climbing or braking stability loss, cornering feels no slower unless the small amount going to 650b front-only. The overall improvement to 650b both ends is almost overwhelming, about as much as upgrading to the Mojo from a previous shorter travel efficient bike.

    Few riders of any brand 26 inch bike converted to 650b, and no Mojo 650b riders I'm aware of, have returned to 26 inch wheels, even if 650b front-only.

    Sorry if I'm being over fanatical. You've got to try 650b to sense the inspiration for my enthusiasm.

  13. #13
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    I'm joining the club. Going to try 650b front and back. I just need some parts to switch to 20mm and 10mm thru axles.
    A bicycle will take you to fantastic places....if you let it.


    Ibis fan since '08 now rolling on the big wheeled Ripley.

  14. #14
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    Quote Originally Posted by 4212darren
    I'm joining the club. Going to try 650b front and back. I just need some parts to switch to 20mm and 10mm thru axles.
    Be sure to heli-tape your chainstay yoke if going to trimmed neo in back. I got a pretty big rub the other day, not sure how it happened but I imagine I went a bit sideways on a landing...anyway, the tape handled it well.
    I keep forgetting to mention once my rear tire got a lil worn I flipped it and really seemed to get a bit more traction with the arrows on the neo in rear pointing the opposite way. This may make it wear a bit faster, but seems to provide better climbing traction. (There seemed to be some slipping on the center arrow shaped knobs once the tire was worn.)
    Last edited by ghawk; 12-28-2008 at 05:32 AM.

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