Can someone do a rough power calc for me?

Discussion in 'Cycling Training' started by Aztec, Mar 8, 2004.

  1. Aztec

    Aztec New Member

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    Sorry to ask something so lame of the group... Can someone calculate what the generic power required is to hold 25.5mph with a 175lb combined weight rider and bike on a flat with no wind?

    Thanks for any help. I want to compare this to what my HAC4 thinks.
     
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  2. SLS

    SLS New Member

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    Frontal Area 0.50 m2
    Coefficient Wind Drag 0.50 dimensionless
    Air Density 1.056 kg/m3
    Weight 79.4 kg
    Coefficient of Rolling 0.004 dimensionless
    Grade 0.000 decimal
    Wind Resistance 17.2 kg m/s2
    Rolling Resistance 3.1 kg m/s2
    Slope Force 0.0 kg m/s2
    Cadence 100. rev/min
    Crank Length 170. mm
    Pedal Speed 1.78 m/s
    Average Pedal Force 129.8 kg m/s2
    Effective Pedaling Range 70. degree
    Effective Pedal Force 333.8 kg m/s2
    Speed 11.40 m/s
    Power 231.1 watts

    Here is the web page if you wish to play with the numbers
    http://www.analyticcycling.com/ForcesPower_Page.html

    Hope this helps.
     
  3. acoggan

    acoggan Member

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    I think you miscalculated air density using the forms on Tom's site. Either that, or you assumed moderate altitude...
     
  4. SLS

    SLS New Member

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    I went with 1500 feet instead of sea level & slipped the gradient down to 0 due to "flat road" - sorry I should have pointed that out. Thanks
     
  5. Aztec

    Aztec New Member

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    Whoops -- I should've mentioned altitude. About 10 measly feet above sea level. Right along the coast.

    Thanks for the help!
     
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