As far as the driver is concerned, road handling is above all measured by the extent to which the vehicle responds to the driver's actions. Everything should run smoothly, consistently and without any surprises.
For car manufacturers, road handling is one of the major aspects of performance. Linked as it is to safety and driving pleasure, performance in this area is a deciding factor for tyre approval. Indeed, it is one of the performances most commented on by professionals (opinion leaders and at press events), as well as by drivers.
Handling development is particularly complex as it depends on a range of factors at three different levels, namely:
• the vehicle (geometry and weight distribution),
• the elements involved in ground/vehicle contact (tyres, steering and suspension),
• the driving assistance systems (stability control and the steering axle).
The tyre plays a key role in road holding because at the end of the chain it ensures the transmission of the efforts between the vehicle and the ground to maintain the trajectory defined by the driver.
The handling performance of tyres is assessed through a number of tests (both objective and subjective, on dry ground, wet ground and on machines).
Road handling is mostly repairable by doing a geometry. But in case of a big impact, the mechanical parts of the vehicle can be affected and damaged.