Revolutionising High Performance Chain Drive Testing: A Precision Dynamometer with Empirical Bearing Friction Compensation

In elite competitive cycling, where races are won by the smallest of margins, bicycle hardware is under continuous optimisation. However, such is the maturity of today’s bicycles that step changes are implausible and efforts are instead focussed on achieving marginal gains. To meet this need, we present a bespoke chain dynamometer system together with a novel empirical method of compensation for the losses in support bearings, and an associated experimental methodology for high-fidelity emulation of real-world conditions. The dynamometer support bearings’ frictional moments are characterised using a secondary experiment. Independent repeats of a baseline chain and lubricant combinations across multiple test campaigns have yielded a bounds uncertainty of <1.75% of the measured power loss at the 99% confidence interval.