A cyclist expends power to overcome a number of forces including gravity, air resistance or aerodynamic drag, acceleration, rolling resistance, wheel bearing and drivetrain friction. Fortunately it has long been possible to reflect all of these forces in a mathematical model of cycling power such that we can understand with high precision the power a rider would need to produce to achieve a certain speed or event time or conversely the speed or time that could be expected for a given power output. We incorporate such a model into the following calculators which can be applied to practical analysis of racing.

## Power Components Calculator

Use this model to calculate the power output required to achieve a certain time on a simple one-sector course or to understand how required power output is spent in terms of components required to overcome the different forces of resistance.

## Power-Speed Scenarios Calculator

Use this model to study the impact of several variables on required power, given a certain speed, or on speed given a certain power output. The kinds of variables you can study include weight, road gradient and aerodynamic drag.

## Power Sector Model (Time Trial) Model

This is a 10 sector course model that can be used to model power, speed or time applicable to events such as time trials and cyclo sportives. As an extension you can easily study the impact of air pressure on time trial performances.

## Variable Power Pacing Model

Use this model to experiment with variable power pacing strategies while checking that your pacing plan remains within the limits of the rider critical power curve.

## Velocita Ascencionale Media

VAM or "Velocity Ascended, Metres Per Hour" is a metric of climbing ability developed by Doctor Michele Ferrari.

## Effects of Altitude

Both a physiology and a power & speed model. Use it to evaluate the tradeoff between reduced power due to oxygen sparsity and aerodynamic benefit of thin air in terms of the combined effect on a riders speed at altitude.

You know your power, weight and the gradients of the climbs you will be riding in a target event. But what gearing do you need? This calculator combines a "speed given power" and a "cadence given gearing" calculator so that that you can accurately determine a comfortable minimum gear.

## Tyre Selection

Rolling resistance is the second most important use of a rider's power after aerodynamic drag. But which tyres choices can help you reduce it, and what are the differences between clinchers and tubulars, butyl and latex inner tubes? This calculator can tell you.

## Acceleration and Wheel Inertia

Acceleration is an important part of bunch or criterium racing and sprinting. This model allows you to study the power cost of rider and bike weight in this so-called "non steady state" cycling as well as the importance of wheel weight and inertia, a key consideration when shopping for wheels.

## The Hour Record

How far can a cyclist go in an hour? It's a beautifully simple challenge with a beautifully simple answer - but it depends! Use this compact utility to model or estimate an hour record performance on any of the velodromes used historically or planned for future record attempts.