Honda CB450, CB450SC & CM450 Shop Manual Collection, 1982–1985 (P/N 61MC003)

The addenda supplement the base repair procedures with model-specific information. The 1983 update covers the CB450SC, CM450A, and CM450E, while the 1985 update applies to the CB450SC.

Honda identifies the covered model years as 1982, 1983, and 1985. Honda did not produce 1984 CB/CM450 models.

Chapter PDFs and Wiring Diagram Readability

Search and navigation: Text search is unavailable. The final PDF has working bookmarks to the 1985 addendum and Service Tool News. Small wiring labels are legible when zoomed in.

The ZIP contains 328 pages in 27 printable PDFs. The shop manual comprises 298 base pages, including its original cover and front matter, plus the 11-page 1982, 5-page 1983, and 10-page 1985 addenda. The two service publications occupy the last four pages of the final PDF and are included in the total.

Engine Overhaul, Drivetrain, and Electrical Tests

These are selected workshop procedures. The manual also covers starter clutch removal and instrument service.

• Engine overhaul: Cylinder head and piston service, crankshaft and balancer work, bearing selection, and internal transmission disassembly and reassembly.
• Carburetor service: Vacuum piston inspection, accelerator pump inspection and adjustment, carburetor synchronization, and pilot screw adjustment using the idle-drop method.
• Clutch and torque converter: Wet multi-plate clutch service and separate CM450A procedures for primary drive inspection and torque converter stall-speed testing.
• Chassis and brakes: Front fork overhaul, steering-head bearing service, swingarm work, and hydraulic master cylinder and caliper rebuilding and bleeding.
• Electrical diagnosis: Alternator, regulator/rectifier, CDI, electric starter, and safety switch tests, with model-specific wiring diagrams and symptom charts.

The manual suits mechanics familiar with standard workshop procedures and equipped with special tools for jobs such as valve-guide replacement.

Engine and Transmission Repair

Cylinder head, cylinder, and piston work can be done with the engine in the frame. Crankshaft, balancer, and internal transmission work require engine removal. Top-end procedures cover valve-guide replacement and reaming, valve-seat refinishing, and camshaft timing. Bottom-end procedures use Plastigage checks and color-coded charts to select crankshaft and connecting-rod bearings.

The lubrication diagram accompanies oil pump rotor inspection and pressure relief valve service. For the CM450A, the transmission section covers the stator shaft, seal rings, and the gear shifter’s steel balls. The kickstarter has its own procedures. If the engine runs but the motorcycle won't move in gear, the stall-speed troubleshooting chart helps distinguish torque converter faults from gear-specific problems.

Carburetor Updates and California Emissions

Fuel-system coverage includes air cut-off valves, float level, fast idle, and high-altitude settings. The carburetor separation procedure identifies the joint pipes and choke linkage as points that can be damaged during disassembly. The CM450A bulletin illustrates installation of Spring Collar Kit 16020-MC1-305 and specifies wider-gap spark plugs for the low-speed, part-throttle complaint.

The 1985 CB450SC fuel tables distinguish the VB2EA 49-state carburetor from the VB2FA California version. The California section pairs its vacuum hose routing diagram with charcoal canister hose checks and purge control valve vacuum and airflow tests for hard hot restarts. Honda cautions against high-pressure air sources for this valve.

Forks, Brakes, and Electrical References

The CM450E has separate front drum brake and conventional fork procedures. Rear chassis coverage includes hub dampers, drum brakes, wheel bearings, rear shock spring removal, damper inspection, and swingarm bushings. Air-assisted forks hold air and spring pressure. Follow Honda’s pressure-release and motorcycle-support precautions before fork work.

Illustrations include clutch exploded views and CB450SC cable and harness routing. The electrical sections cover the CM450A change relay and side-stand ignition circuit. CDI test tables specify tester types and ranges because unsuitable equipment can give false readings. The tool sheet identifies rotor puller 07933-3950000 as the substitute for 07733-0020001.

Sample Valve Clearance and Stall-Speed Specs

Factory tables include fastener torques, compression test data, wear limits, and separate oil quantities for a refill and for assembly after teardown. Maintenance procedures cover cam chain tension, balancer chain tension, and ignition timing.

For the base models, the manual specifies 0.10 mm (0.004 in) intake and 0.14 mm (0.006 in) exhaust valve clearance with the engine below 95°F (35°C). For the CM450A torque converter, Honda lists 3,550–3,850 rpm as the standard and 3,400 rpm as the service limit for the warm-engine, first-gear, full-throttle stall test.