What is Performance Analysis? Performance Analysis uses quantifiable computer data to improve your efficiency and speed through positioning. Your efficiency and speed on a bicycle is determined by four main variables: power, oxygen transfer, technique and aerodynamics. You don’t want to just maximize one at the expense of the others. Instead, you want to find…
Because I work with a large range of athletes, from pros and top age groupers to people buying their first road or tri bike, I thought a bit of perspective on positioning might be helpful as there is a lot of often contradictory information about proper positioning and fit technicians out there. Many industry triathlon…
As a solo rider, you do not have the benefit of being protected from the wind by a peloton of other riders as you would in a road race. When you are riding on your own, overcoming air resistance uses 65-70% of your energy. An aero position is designed to help you maximize your aerodynamic…
By Ian Buchanan Much of the bicycle industry has done a good job of creating the impression that different materials offer different ride characteristics. Aluminum is supposed to be stiff and light, but is also known for diminished durability and harsh ride quality; Titanium is supposed to be light, durable, comfortable and compliant, but a…
By Sarah Shorett, co-owner of Fit Werx Frame geometry differences can be a complicated subject. Hopefully this article can help make it a little simpler. Think about bike geometry as you would shoes. There are many different types of shoes and all have a distinct purpose. If you are going for a hike on trails,…
Frame Geometry and Handling – Energy and Power Use Breakdown* % of Total Power Consumption: Frame Geometry and Handling: Intangibile. The bottom line: A bike’s geometry and design combines with your position on it plays a large role in how comfortable you are on the bike, how stable the bike is, and how well it…
Mechanical, Compatibility & Friction – Energy and Power Use Breakdown* % of Total Power Consumption: Mechanics, Compatibility and Friction: 2%-100% of overall energy/power consumption The bottom line: Friction from an adequately maintained drive train, etc. can use up to 2% of your energy. Component incompatibility and mechanical issues are deal breakers. From flat tires and…
Weight of Bicycle – Energy and Power Use Breakdown* % of Total Power Consumption: Weight of Bicycle: ≈08% of overall energy/power consumption The bottom line: First, never forget that you the rider are 85-95% of the total vehicle’s weight – the bike and components are only 5-15%. Bicycle weight plays a comparatively small role in…
Rolling Resistance Energy and Power Use Breakdown* % of Total Power Consumption: Rolling Resistance: ≈10% of overall power/energy consumption The bottom line: Rolling resistance is affected by friction caused by the weight of the vehicle (bike and rider) and how much of that weight has to be absorbed by the tires while riding. Rolling resistance…
Stiffness & Compliance – Energy and Power Use Breakdown* % of Total Power Consumption: Stiffness and Vertical Compliance: ≈15% of overall energy/power use The bottom line: Unless a design uses an effective suspension system, side-to-side stiffness and vertical compliance/comfort will be directly linked. In almost a 1:1 ratio and regardless of material, as a frame…
Bicycle Aerodynamics Energy and Power use breakdown* % of total power consumption: Aerodynamics Total (combination of rider aerodynamics and bike aerodynamics) – 65-85% Total Bicycle Aerodynamics ≈15% of total power use and ≈25% of total aerodynamics Wheels – 5-9% of total aerodynamics Fork – 6-9% of total aerodynamics Frame – 4%-9% of total aerodynamics Other…
Rider Aerodynamics (Fit and Positioning) Power Use breakdown* % of Total Power Consumption: Rider Aerodynamics: ≈50% of total power use (75% of total aerodynamics) The bottom line: If you are on a solo ride and average 20 mph over a 100 miles of varied terrain, lowering aerodynamic drag by 10%, without changing power output, will…