In order to achieve high driving performance, a maximum excess traction force is necessary. As far as this is concerned, the points of intersection of the characteristics of the excess traction force in the respective gears represent the correct shifting point between neighboring transmission levels in regard to the optimal accelerating ability in stepped transmissions. These points of intersection are shifted towards lower speeds as a result of the mass factor (see figure).
The optimum shifting points in reference to the maximum climbing ability in a constant velocity drive, lie at the points of intersection of the characteristics of excess traction force. Thus they lie within the points of intersection of the power curves independent of the mass factor.
In contrast to stepped transmissions, CVTs offer the possibility to freely choose the engine operating point for a prescribed power demand. With a corresponding control strategy, the engine can be operated constantly at the point of maximum power output. The vehicle has an optimum climbing and accelerating ability.