Loading guide...
Workshop Walkthrough
A four-stage preview of a 1967-1977 Norton Commando restoration. The teardown stage walks the separated-sump drain, cam-ring orientation, and three-stage reverse-torque head lift. The engine stage plays the full 750 / 850 top-end procedure on-canvas, including the bore-class audit (71 / 77 / 77.1 / 77.8 mm) and the three-stage head re-torque. The wiring stage previews the three-era Lucas electrical split (MA12 + Zener + points / RM15 + Rita / 850 Rita SSI). The reassembly stage ends at the cold tappet reset.
Teardown: Drain the engine sump and the primary case separately (the Commando does NOT share a sump), mark the cam-ring orientation to the crankshaft pinion -- orientation is non-symmetrical on the Atlas-derived twin -- then remove the cylinder head in the three-stage reverse-torque sequence (28 -> 21 -> 14 N.m) with the slip joints free first.
Workshop Walkthrough
Watch the on-canvas build first, then run the numbered steps below at the bench. Still frames pin to the matching step in the procedure list.
If the inline player will not start, download the walkthrough (MP4).
Family reference
Loading guide...
Read next
A workshop-grounded walkthrough of scope, tools, time, model choice, and the pitfalls first-time restorers hit hardest — written for the reader who has not yet picked a bike.
Open the getting-started pillarRead next
BSA DOHC single-cylinder (1938-1963) -- DBD34 rigid-rear (1938-1948), YA / ZA / ZA-B Golden Flash plunger-rear (1949-1958), DBD34GS Clubman swinging-arm (1956-1962), 1959 Catalina scrambler with Lucas RM13 alternator + negative-earth switchover, and B50SS Clubman continuation (1961-1963). DOHC shim-under-bucket wedge spec (I 0.10 / E 0.15 mm), BTH fotQ versus Lucas W2 / W3 stand-alone magneto split, and the 1956 swinging-arm chassis pivot.
Open the BSA Gold Star Restoration GuideRead next
Triumph unit-construction 649cc / 750cc parallel twin (1963-1979). Lucas E3L dynamo 1963-1968 transition to RM15 alternator + WIPAC diode-board chassis 1969-on, 1968-1969 ground-polarity switchover, Amal 930 (1963-1968) to Amal 932 (1969-on) carb size step, 1971 twinshock to Uni-Trax rear suspension, factory tolerances per sub-model across the Meriden / T120 / T140 production run, and the 14-step factory concours assembly sequence.
Open the Triumph Bonneville Restoration GuideRead next
Triumph pre-unit parallel twin (1937-1959). BTH fotQ magneto splitting the 5T Speed Twin, T100 Tiger 100, TR5 Trophy, TR6 Trophy, and T110 Tiger, BTH-versus-Lucas W2 / W3 stand-alone magneto split on the pre-unit BSA Gold Star sister bike, Magdyno positive-earth harness, and Atlas-style mainshaft / gearbox retrieval tolerances.
Open the Triumph Pre-Unit Restoration GuideRead next
BSA brand-pillar covering the A-series rigid-rear (1946-1963), B-series alloy-head unit-construction (1964-1972), A50 / A65 alloy-head twins, and the Gold Star DOHC single. Includes year-by-year model chart, model-specific tool list, BSA factory service sheet extraction, and the diagnostic matrix covering the magdyno + Amal concentric CV / Premair carburettor pairings.
Open the BSA PillarRead next
Kawasaki 748cc air-cooled three-cylinder two-stroke (1969-1975). Pre-mix oil pump calibration (factory 32:1 under run-in, 40:1 after break-in), Mikuni VM26SC triple-carb sync band (+/-2 cmHg on the three-cylinder stack), CDI trigger pickup air-gap window (0.6-0.8 mm H2 / H2A narrows to 0.4-0.6 mm on H2B / H2C / KH500), and the H2 / H2A / H2B / KH500 model-year deltas including the optional oil-injection delete on the late H2 / H2B / H2C.
Open the Kawasaki H2 Mach IV Restoration GuideRead next
BMW R90S /6 sport flagship boxer-twin (1973-1976, 898cc). Twin-disc front brake (R90S only), Bing 94 slide-carb pair, long-shaft 33/11 final-drive unit, and the 1973/74 mid-model-year ground-polarity switchover from positive to negative earth. Covers the factory contact-breaker points ignition on early 1973 /6 production AND the factory Hella electronic ignition retrofit kit on the late /6 1974-1976 production.
Open the BMW R90S Restoration Guide