Abstract: Dynamometer apparatus for measuring the performance of a wheeled vehicle comprising: a support assembly on which the vehicle may be supported; power absorption apparatus mounted on the support assembly for engagement with at least one wheel of the vehicle; a pump connected to the power absorption apparatus for producing a fluid pressure in response to the torque produced by the vehicle wheel; speed measuring apparatus mounted on the support for engagement with the vehicle wheel to indicate the surface speed thereof; and indicator apparatus connected to the pump and the speed measuring apparatus for correlating fluid pressure and surface speed with the performance of the vehicle.