PURPOSE: To obtain the conditions close to the actually running state by arranging drums vertically, and converting the rotations of tires into the rotations of vertical drum shafts.

CONSTITUTION: Planar drum plates 7 are arranged so as to correspond to tires 8a of an automobile 8. Each plate is arranged on a supporting stage 9 with a vertical shaft 7a. The planar drum plate 7 which is driven by the tire 8a of the automobile 8 that is arranged on the planar drum plate 7 directly drives the shaft 7a of a main body 1 of a dinamometer. The turning force is directly taken out with the main body 1 of the dinamometer as turning torque. Thus the performance of the automobile 8 can be confirmed. An angle θ is provided on the upper surface of the planar drum plate 7. Thus, the heat which is generated by the difference in peripheral speeds of the inner and outer parts of the wheel of the tire 8a can be compensated with the difference in pressure receiving areas. In this way, the contact surfaces between the planar drum 7 and the tire 8a of the automobile 8 under test can be made equivalent to that in the normal conditions, and the conditions close to the actual running can be obtained.