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Discussion in 'Boat Design' started by Guest625101138, Jul 14, 2008.

  1. jehardiman
    Joined: Aug 2004
    Posts: 2,507
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    Location: Port Orchard, Washington, USA

    jehardiman Senior Member

    We abandoned them for submerged HPV's because the "power units" didn't like the "I thought I broke it" feeling as the pedal pressure gave way at the end of the stroke. We replaced them with "stair-stepper" units and everyone like that better as well as having better physical arrangement.
  2. portacruise
    Joined: Jun 2009
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    Location: USA

    portacruise Senior Member

    Elliptical sprockets are more prone to having the chain fall off on a derailleur shifting arrangement because of the non circle shape would be be my guess.
  3. BlueBell
    Joined: May 2017
    Posts: 983
    Likes: 135, Points: 43
    Location: Victoria BC Canada

    BlueBell Ahhhhh...

    One reason high cadence works well on a bicycle is the cyclists ability to even the power delivery.
    The same can be said for clip-in pedals, not the strap variety, but the quick release "click" ins.
    When I was racing, the coach would tell us to imagine spinning, not pounding.
    The bio-pace chainrings were fine, I had a set.
    Felt very strange, broken as John says.
    I took them off and sold them.
    I like the flywheel idea but not for the weight penalty...

    Edit: I didn't have any problems with the chain falling off.
    The spring loaded derailleur had no problem taking up the slack.
    kerosene likes this.
  4. portacruise
    Joined: Jun 2009
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    Likes: 28, Points: 48, Legacy Rep: 218
    Location: USA

    portacruise Senior Member

    Curious if the bio pace sprocket had to be aligned with a timing mark on the bike chain?

  5. Squidly-Diddly
    Joined: Sep 2007
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    Location: SF bay

    Squidly-Diddly Senior Member

    I had a Bio-Pace on typical MTB. Timing mark wouldn't make sense because only the front gears were Bio (normal 3 gear front) so as you'd shift the rear sprocket the chain links would "just do what they do" and average out position at any one time.

    As far as the Bio Pace itself? Seemed pretty good. Never noticed it unless I switched to regular bike and tried to notice. Not sure why its not standard. I guess the tensor roller spring gets a workout, and the lower-return part of chain goes up and down.
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