1975 Norton 850 Commando Mark 3 Workshop Manual (P/N 00-4224)

• Covers the 1975 Norton 850 Commando Mark 3 with electric start, detailing Interstate, Roadster, Hi-Rider, and Interpol configurations
• Official Norton Triumph International publication No. 00-4224
• Packs 56 detailed exploded-view diagrams, 27 torque specification tables, and a fully illustrated electrical wiring layout
• Documents the critical engineering transition to the electric-start, left-foot-shift Mark 3 build

Manual Contents and Engine Systems

This technical documentation breaks down the complete powertrain. You get a direct look at the air-cooled 828 cc engine and the Mark 3 specific electric start mechanism. Detailed sections cover cylinder head servicing, decarbonizing procedures, and valve guide replacement. It also maps out crankshaft reassembly sequences step by step. The text dives deep into specialized transmission servicing. You will find the 4-speed gearbox internals, selector fork inspection parameters, and the primary drive assembly for the left-foot-shift model. Lubrication system data is fully laid out for maintenance and overhauls, highlighting the oil pump and anti-leak valve modifications unique to this series.

Specifications and Dimensional Data

Expect heavy technical data. Comprehensive tables map out all major motorcycle systems, including chassis, engine, and electrical specs. The manual provides precise tightening torques in both lbf/ft and kg/m for engine mounts, cylinder head bolts, and crankshaft components. Crucial dimensions are clearly listed, such as the 0.006-inch intake valve clearance and the 150 cc front fork oil capacity per leg. Ignition timing for the fully advanced position is dialed in at 28° BTDC. Restoring classic British motorcycles exposes you to heavy lifting, combustible fluids, and electrical hazards. Always ventilate your workspace properly, disconnect the battery before inspecting the wiring harness, and verify part integrity before applying final torque.