Bicycle Power Calculator

Assumptions:
Constant speed analysis, Bike weight = 22 lb, 12 speeds
27" diameter wheels, 6.75" pedal crank, 95% mechanical efficiency
Drag coefficients reference "Science of Cycling", E.R. Burke, Leisure Press, 1986, pg 126.

Inputs
Desired Constant Speed (mph)       Rider's Weight (lbs)
% Grade (+ for uphill,- for downhill)
Gear Ratio (#Teeth Rear/Front)
Air Resistance Coefficient (lbf*s^2/ft^2)
Rolling Resistance Coefficient

Calculated Outputs
Total required input power from the rider       HP
Power needed to overcome air resistance      HP   %
Power to overcome rolling resistance in tires HP   %
Power needed for elevation change               HP   %
Power lost to mechanical losses, friction, etc. HP   %
Calories burned per mile kcals
    Average Pedal Force Lbs     Average Traction Force Lbs
    Pedal Speed RPM                Tire Speed RPM

23 June 1998 by John S. Lamancusa - Penn State University (jsl3@psu.edu)
Accuracy checked by ME288 Product Dissection class
Modified to work with Netscape 4.0 by Matt Lindenberg

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