A tire-wheel assembly must be balanced. As the wheel rotates, centrifugal force acts outwards. Any heavier part will vibrate vertically, and slap the road surface with each wheel revolution.
Automated Tire Pressure Monitoring Systems or TPMS provide a means of reliable and continuous monitoring of the vehicle tire pressure and are designed to increase safety, decrease fuel consumption and improve vehicle performance.
Space-saver spares are for emergency use only, they're designed to get you to a service center where you can have the regular tire fixed or buy a new one.
During cornering, tire distortion makes a vehicle move at an angle to the direction of the wheels, called slip angle. Cornering force returns the tire to normal position. As cornering force increases, so does slip angle.
The center of gravity is the balance point of the entire vehicle. Its position is determined by the load on the front and rear wheels. It is always above the road, and between the tires.
