High Quality Content by WIKIPEDIA articles! A cycling power meter is a device on a bicycle that allows measuring of the power output of the rider. Most cycling power meters use strain gauges to measure torque applied, and, combined with angular velocity, calculate power. The Technology was adapted to cycling in the late 1980s and was tested in professional bicycle racing i.e.: the prototype Power Pacer (Team Strawberry) and by Greg LeMond with the SRM device. This type of power meter has been commercially available since 1989. Power meters using strain gauges are mounted in the bottom bracket, rear freehub, or crankset. Certain newer devices do not use strain gauges and instead measure power through handlebar-mounted units that utilize the principles of Newton`s Second Law by measuring a cyclist`s opposing forces (gravity, wind resistance, inertia, rolling resistance) and combining these with velocity to determine the rider`s power output.