Source of Equation |
Whitt, F.R. & Wilson, D.G., "Bicycling
Science". MIT Press, 1982 |
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Author of Spreadsheet |
Dr Charles Coin, Director of Biketech, biketech@powerup.com.au;
Tel 07 3278 1391; Fax 07 32781392; P.O. Box 144 Sherwood 4075, Qld |
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Notes on Equation |
K1 & K2 are constants which vary according to the type
of bicycle - |
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K1 |
K2 |
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7.845 |
0.3872 |
Roadster bike which is heavy with upright handlebars |
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3.509 |
0.2581 |
Sports bicycle of medium weight with dropped handlebars |
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2.508 |
0.1916 |
Racing bicycle, lightweight with dropped handlebars |
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There is an acceleration factor in the equation which is
not utilised in the big sheet and hence it is assumed that acceleration
that is not gravitational is of minimal effect. |
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Notes on Working Sheet |
This is a rudimentary sheet which I use the last column to
put in the data on the persons best 40 km TT time and thence work out
their steady state power. |
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Notes on Mt Cootha Sheet |
To use this optimally, alter the individual speeds [pink
column] for each increment until a selected wattage [green column] is
achieved. |
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Note that the weight considered must of the bicycle plus
the rider. |
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The heights were measured using a barometer which was
calibrated in feet with the increments to the nearest 10 ft. |
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The distances were measured using the odometer of the Audi
A4 and were estimated to the the nearest 0.05 km. Smaller increments were
to exactly 0.1 km |
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Uses of the Spreadsheet |
To set up suitable schedules for road TT courses. The
course will need to be surveyed into segments and slope of each segment by
using an altimeter [or barometer]. |
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To run experiments of variable power output and its
consequences, i.e. we usually work harder uphill and ease up or coast
downhill. This way the efect of each strategy and the total work done can
be seen. Try and keep the the total work constant and vary the power input
for each increment for the best time. |
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To do "what if" cases of reducing weight,
increasing power etc. |
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Comparing two riders over the same course will show that
each may have the advantage at various stages during the course. |