Target Audience:
Honda motorcycle owners and independent repair shops servicing the CB400 and CM400 models from 1978-1981.
Value Proposition:
Provides essential factory-level technical data for maintenance and repair, crucial for preserving the longevity and performance of these classic Honda motorcycles.
Manual Completeness:
Covers both CB and CM variants, manual and automatic transmissions, and multiple model years through included supplements, offering broad applicability.
Model Years Covered:
1978, 1979, 1980, 1981
Transmission Coverage:
Manual Transmission (5-speed), Automatic Transmission (2-speed Hondamatic)
Supplementary Coverage:
Includes supplements for 1978, 1979, 1980, 1981 models, indicating updates and variations across these years.
Estimated Page Count:
Approximately 300-400 pages (includes main manual and supplements). Exact count not specified, but described as 'complete'.
Manual Type:
Factory Service Manual / Repair Manual
Format:
Print (physical book)
Engine And Drivetrain:
Engine disassembly, assembly, tuning, lubrication, cooling system, fuel system (carburetors, fuel pump), ignition system (points, coils, timing), exhaust system, transmission (manual and automatic), final drive (chain).
Chassis And Suspension:
Frame inspection, front fork assembly and overhaul, rear shock absorber inspection and replacement, steering head bearing maintenance, wheel and tire service, brake system (front and rear drum/disc), control cables.
Electrical System:
Wiring diagrams, battery, charging system (alternator, rectifier/regulator), lighting (headlight, taillight, signals), ignition switch, starter motor, horn, instrument cluster.
Bodywork And Trim:
Body panel removal and installation, seat, fuel tank, fenders, handlebars, controls, trim pieces.
Maintenance And Tune Up:
Regular service intervals, oil changes, filter replacements, spark plug service, carburetor synchronization and cleaning, valve clearance adjustment, brake adjustments, chain lubrication and adjustment, battery care.
Troubleshooting:
Diagnostic procedures for common starting issues, engine performance problems, electrical faults, braking issues, and transmission problems.
Repair And Rebuild:
Detailed step-by-step instructions for engine overhauls, carburetor rebuilds, transmission servicing, brake caliper/master cylinder servicing, fork seal replacement, and electrical component repair.
Depth Of Coverage:
Comprehensive, covering all aspects from basic routine maintenance and adjustments to full engine and transmission rebuilds. Includes torque specifications, clearances, and diagnostic flowcharts.
Print Quality:
Described as 'Clean, complete with no missing pages', implying good original print quality.
Binding Type:
Likely staple-bound or perfect-bound for factory manuals of this era.
Paper Type:
Typically durable paper stock suitable for workshop use.
Engine Type:
Air-cooled, 4-stroke, SOHC parallel-twin
Displacement:
395 cc (395 cubic centimeters)
Bore X Stroke:
67.0 mm x 55.5 mm
Valve Train:
SOHC (Single Overhead Camshaft), 2 valves per cylinder
Horsepower Approx:
Approx. 35-40 HP @ 9,000 RPM (varies slightly by year/model)
Torque Approx:
Approx. 23-25 lb-ft @ 7,000 RPM (varies slightly by year/model)
Carburetion:
2 x Keihin constant velocity (CV) carburetors, 30 mm (CB400T/CM400T) or 32 mm (later/specific variants)
Fuel Tank Capacity:
Approx. 10-12 Liters (2.6-3.2 US Gallons)
Ignition Type:
Electronic Ignition (CDI) with points for timing reference in early models, progressing to full electronic ignition.
Overall Length:
Approx. 2150 mm - 2250 mm (varies by model)
Overall Width:
Approx. 800 mm - 850 mm (varies by model)
Overall Height:
Approx. 1150 mm - 1250 mm (varies by model)
Dry Weight:
Approx. 170 - 185 kg (varies by model)
Wet Weight:
Approx. 185 - 200 kg (varies by model)
Safety Standards:
Met all applicable safety regulations for motorcycles of its era (e.g., DOT standards for lighting).
Braking System:
Front: Single disc brake or drum brake. Rear: Drum brake.
Suspension Performance:
Front: Telescopic forks. Rear: Swingarm with dual shock absorbers.
Frame Construction:
Steel cradle frame providing structural integrity.
Instrumentation:
Analog speedometer, tachometer, odometer, trip meter, and indicator lights (neutral, oil pressure, turn signals, high beam).
Safety Features Era:
Focus on fundamental mechanical systems rather than electronic aids. Safety relies on rider skill and well-maintained braking/suspension.
Connectivity Features:
N/A (No electronic connectivity features)
Oil Change Interval:
Recommended every 3,000 km (approx. 2,000 miles) or 6 months, whichever comes first.
Valve Adjustment Interval:
Recommended every 6,000 km (approx. 4,000 miles) or 12 months.
Spark Plug Service:
Inspect every 6,000 km, replace as needed (typically every 12,000-18,000 km).
Engine Oil Type:
SAE 10W-40, API SE or SF grade motorcycle oil.
Engine Oil Capacity:
Approx. 2.0 - 2.2 Liters (with filter change).
Fork Oil Type:
Honda Suspension Fluid SS-8 or equivalent SAE 10W fork oil.
Fork Oil Capacity:
Approx. 160 cc per fork leg.
Carburetor Issues:
CV carburetor diaphragms can degrade over time, leading to poor throttle response. Needle jets can wear. Periodic cleaning and synchronization are essential.
Ignition System Wear:
Points and condensers (on early models) require regular maintenance. Stator and ignition coils can fail with age.
Cam Chain Tensioner:
Automatic cam chain tensioner can sometimes fail, leading to rattling noises. Manual adjustment or replacement is an option.
Brake Wear:
Drum brakes require periodic adjustment. Disc brake pads and fluid should be checked and replaced as needed.
Hondamatic Transmission:
While generally reliable, the Hondamatic requires specific fluid levels and occasional servicing of the torque converter.
Honda Motorcycles 1970S:
Honda was a dominant force in motorcycling, known for reliable, technologically advanced, and accessible bikes. The CB/CM series represented a strong offering in the mid-size segment.
Cb400 Lineage:
The 400cc parallel-twin engine platform was a staple for Honda, evolving from earlier models and providing a versatile base for both sporty (CB) and cruiser (CM) variants.
Production Period:
The CB400/CM400 series was produced from the late 1970s into the early 1980s, serving as a popular middleweight option.
Industry Reputation:
The CB/CM400 series was well-regarded for its reliability, smooth parallel-twin engine, and versatility, making it a popular choice for commuters and leisure riders.
Performance Reviews Era:
Contemporary reviews often praised the balanced handling, user-friendly power delivery, and fuel efficiency of the 400cc twins.
Certification Standards:
Manufactured to meet global motorcycle safety and emissions standards applicable at the time of production.