A bus is a kind of vibration damper for the chassis of the car. Often rubber, but also special variants of polyurethane are possible. It offers a secluded connection between two suspension parts. Where the bus dampens the energy of the two parts and allows only free movement for hinging. As a result of this hinging, the suspension parts can move freely at, for example, a pit in the road, while it dampens small vibrations and sounds. These can be found on the shock absorber attachments, suspension arms, gearshift and track rod.
Often these bushings are in the form of an annular cylinder and there is a flexible material in the metal housing or outer tube. They can also have an internal crush tube that protects the bush against pinching of the part where it is screwed. The advantage of these buses is that they bring less noise and vibration than a fixed connection and no lubrication is required.
By default, there is already a lot of room for improvement of the buses and its driving characteristics. In addition, the buses are subject to wear. Worn rubbers can adversely affect the driving characteristics. They can also provide unwanted noises. A disadvantage of rubber is that it can deteriorate due to contact with oil, fuel, extreme heat or cold.
KCPerformance has quality buses from daily use to very balanced variants, for even better driving characteristics.