F orces are assumed
to be in equilibrium, steady-state conditions.
Power,
Given Speed
P ower is calculated
based on rider parameters, slope, and speed.
Speed,
Given Power
S peed is calculated
based on rider parameters, slope, and power.
Tire
Rolling Resistance
T ire Rolling Resistance.
How much time can be saved by picking the right tire for a time trial?
Forces
on Rider
F orces on a rider due to slope, rolling resistance, air drag, and wheel drag. Forces are given in grams-force and by percent.
Less Weight
on Hill
T wo riders ride
up a hill. One has less weight. What is the difference between
them in distance and time?
Air Density
A ir Density is
calculated based on links to weather information. Power requirements
depend on Air Density.
M ore often than not, forces on a rider
are not in equilibrium. Under these conditions speeds change
as time progresses.
Wind on Rider

W ind's effect on rider over a caurse of your choice. You set wind speed and direction. You set your wheel drag parameters as function of wind yaw angle.
Rider Aero Study

J ohn Cobb, who does wind tunnel testing for some of the best riders in the world, sent us some of his wind tunnel data. We did an analysis and report the results.
Speed &
Acceleration

P osition, Speed,
and Acceleration are calculated over time based on rider parameters,
slope, power, and initial conditions.
Downhill
Sprint

H ow fast will a
rider go in a down-hill sprint based on rider parameters and
slope. What gear?
Wingate Test

C onvert data from
a Wingate ergometer sprint test to a form that can be used in
subsequent calculations.
Sprint Power

G iven parameters
from a Wingate test or assumed parameters, power is plotted as
it changes with time, simulating sprint power.
Terminal Velocity

T erminal velocity
based on rider parameters, slope, power, and initial conditions.
Flying 200m

E stimate of time
for a flying 200m based on rider parameters, wheel parameters, configuration of 333.3m velodrome, Sprint
Power , and path ridden by rider.
500 m TT

E stimate of time
for a 500 m TT based on rider parameters and Sprint
Power .
Kilo Power

E stimate of time
for a 1000 m TT based on rider parameters and Sprint
Power .
A model of pedaling
a bike is presented. The Model lets one make assumptions regarding
strength of the thigh and shin muscle groups and converts these
assumptions into power at the pedals.
Pedaling Model
Concept
E xplanation of
Pedaling Model.
Pedaling
Model
R anges of motion,
plots of position, and power generated are given based on rider
geometry and thigh and shin strength.
Plot Strength
Functions
P lots strength
of thighs and shins .
Plot Forces
At Pedals
P lots radial and
tangential forces at pedals.
Optimal Seat
Height
O ptimal seat height
based on given rider parameters and thigh and shin strengths.
Optimal Crank
Length
O ptimal crank length
based on given rider parameters and thigh and shin strengths.
"Keep the
heel down"
P ower output based
on different geometries created by keeping the heel up or down.
Improved Muscle
Strength
B enefits from hypothetical
changes to thigh and shin strength.
W heel performance
in various situations is evaluated based on measurements you
can take on your own wheels. Enter data on tire mishaps and analyze it.
Wheel
Aerodynamics
and Inertia
Concepts
C oncept of how
to measure wheel rotational inertia is presented as well as a
explanation of the equations used for evaluation. Wheel aerodynamics
is discussed.
Calculate
Wheel
Inertia
M easure rotational
inertias for wheels. A weighing scale, a stopwatch, and a tape
measure are all that are required.
Table of Wheel
Inertias
T able of rotational
inertias and masses for typical wheels.
Table of Drag
Coefficients
T able of aerodynamic
drag coefficients for various wheels.
Criterium
Corner
C riterium corner:
based on your parameters which wheels give the better performance.
Breakaway
B reakaway: based
on your parameters which wheels give the better performance.
Sprint
S print: based on
your parameters which wheels give the better performance.
Climb
C limb: based on
your parameters which wheels give the better performance.
Pursuit
P ursuit: based
on your parameters which wheels give the better performance.
Mishaps
E nter data on tire mishaps.
Analysis
A nalyze tire mishap data.
Example
A n example shows
how the tools presented here could be used. In the example a
hypothetical rider uses the tools to reduce a time trial time
by 20%.
G ear charts show
"gear inches" and "rollout" for various gear
combinations and wheel diameters.
Gear
Chart
G ear charts based
wheel diameter, "gear inches," and "rollout."
Cadence from Speed
E stimate cadence based on chainring, cog, and speed.
Speed from Cadence
E stimate speed from chainring, cog, and cadence.
Gear Selection
T rack gear selection
based on wheel diameter, air density, rider parameters, expected
speed.
Track
S hows the effect
of rider parameters, air density, and wheel diameter on gear
selection for points race.
Pursuit
S hows the effect
of rider parameters, air density, and wheel diameter on pursuit
times.
Long Climb
G ear selection
for a long climb.

Copyright © 1997 Tom Compton All rights reserved.