Why is InfoCrank® a precision instrument? Because each crank, right and left, is designed expressly around a strain-gauge load cell.
A load cell is a transducer that converts a force into an electrical current, and is used for measuring instruments such as lab and industrial scales.
A single InfoCrank arm is so very accurate because the strain gauge measures only tangential force, or torque—the force the rider puts in that drives the bicycle forwards. The load cell design means that side, radial, and twisting loads that are exerted on the crank (but do not move the bike forward) are not measured.
Every Load cell is calibrated at our laboratory. Independent certification tests on completed InfoCrank® sets have been conducted which showed <0.25% average error across all the normal riding zones. The greatest error in 100 tests was one outlier of 0.57%. No other power meter has achieved such high levels of accuracy with such consistent results.
British Cycling test each InfoCrank® they buy before putting it into work on the bikes (track and road) of the Great Britain Cycling Team, Tests on the Road InfoCranks® showed amazing results. Between zero and 464nm (equivalent to 3000w) the Road InfoCrank error was stable and well under 0.6% at every measurement.
The test result below shows the initial tests on the new Track InfoCrank®. This is the starting point from which we work to improve accuracy to the same level as the Road InfoCrank®.
Our cranks are designed so the Torque meters sit exactly where the maximum force is applied.