The Cubic Capacity (cc) of a vehicle is defined as the volume of the cylinder between the piston top dead center and bottom dead center. Cubic capacity is expressed in cubic centimeters or cubic inches.

An increase in the cubic capacity of a vehicle leads to a higher mileage, higher torque at lower rpms, increased number of pistons and cylinders that increase the speed, smoother running of the engine and more power strokes. As we proceed from less than 100cc to above 180cc, the size of the engine increases and thereby fuel efficiency also increases.

The vehicles in the two wheeler segment have been demarcated on the basis of Cubic Capacity. The different capacities are: less than 100cc, 100-150cc, 150-180cc and greater than 180cc.