FORCE AND MOMENT CHARACTERISTICS OF MOTOR=CYCLE TYRES

Abstract

Experimental investigations of various steady state forces and moments generated due to interaction between dry concrete pavement and (i) free rolling, load bearing tyre and (ii) braked load bearing tyre are carried out on a flat type tyre testing machine developed at this University. A measur- ing system comprising a six component analyser was used to determine the force and moment components. Electrical resistance strain gage type transducers were used for the measurement of the six components of forces and moments acting at the tyre-pavement contact patch. The lateral force, aligning torque and overturning moment components are measured for Srichakra 2.50-18 6 Ply. and 2.75-18 6 Ply tyres at six typical values of normal force and three inflation pressures at different slip and inclinat- ion angles under free rolling and under braked wheel condit-ions. Rolling characteristics of the two tyres are determined for different slip and inclination angles. Transient charact-eristics with respect to a step slip angle input are also investigated. A comparison is made with the available data. Finally various tyre stiffnesses are established as empiric-al functions of the normal load and longitudinal slip.