To aid in the modelling of the performance and to assess the viability of the clock work energy harvester then the car wheel dynamics of a typical small car have been measured. Wheel rotation speed has been measured using a hall sensor and attaching twelve metal disks to the inside of the wheel rim, fig 1a. A bracket was designed, fig 1b, to allow the hall sensor to be attached to the shock absorber and positioned inside the wheel rim close to the metal disks,