Drive Chain: Description and Operation

PRIMARY DRIVE
The primary drive is a triplex chain transmission. A chain tensioner consisting of two spring-loaded, hydraulically damped tensioner pads is located between the two sides of the chain. The oil trap of the chain tensioner housing is continually topped up with oil from the primary chaincase. Non-return valves in the oil ways between the oil trap and the tensioner pad cylinders provide the hydraulic damping.