Bicycle Power Calculator Bicycle Power Calculator
Assumptions:
Constant speed analysis
Bike weight = 22 lb
Drag coefficients reference "Science of Cycling", E.R. Burke, Leisure Press, 1986, pg 126.

Inputs
Wheel Diameter (inches)        Crank Length (inches)
Desired Constant Speed (mph)       Rider's Weight (lbs)
% Grade (+ for uphill,- for downhill)       Mechanical Losses (3-5% is typical) %
Gear Ratio (#Teeth Rear/Front)            
Air Resistance Coefficient (lbf*s^2/ft^2)
Rolling Resistance Coefficient (lbf/lbf)       

Calculated Outputs
Total required input power from the rider       HP     Watts
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

1 June 1999 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