Triumph Unit 650 Primary Cover TR6 T120 1968-1972 PN# 57-2439 70-9245

Description

Although correct for the 1968-1972 Triumph 650 models, this primary chaincase cover is compatible with the earlier unit-construction models where a provision for strobe-timing is desired. This cover can also be fit to the right-shift 1973-1974 Triumph 750 twin-cylinder models with the triplex chain primary drive when the necessary internal modifications are carried out.

The reproduction primary chaincase cover features a nicely polished finish, however, due to the manufacturing process, there may be some visible waves and minute pock-marks in the finished product. The bare cover includes the level plug and sealing washer, but not the timing pointer. Sourced from LF Harris in the UK.

Sealed by a gasket, the chaincase cover houses the alternator and primary drive system. When fitted to the 1963-1972 models with the duplex primary drive chain, there are no modifications necessary. When fitted to the 1973-1974 models with the triplex chain, reliefs must be carefully ground from the cover screw bosses in the interior of the cover to allow for the added width of the primary drive chain and clutch chainwheel. Additionally, a shorter timing pointer must be used to avoid scoring the alternator rotor.

The brake pedal and left-side footrest must be loosened or removed to allow the chaincase cover to be fitted into place. Cover screws are threaded directly into the drillings in the outer rim of the primary drive chaincase. A good quality gasket is necessary to seal the oil in the chaincase, and is fitted between the outer cover and the chaincase.