🏷️ Basic Information

Make:

Kawasaki

Model:

Z250 / KZ305

Model Designations:

Z250 (KZ250A, KZ250B, KZ250C, KZ250D, KZ250E, KZ250F, KZ250G, KZ250H), KZ305 (KZ305A)

Applicable Years:

1979, 1980, 1981, 1982

Chassis Codes:

KZ250, KZ305

👋 Introduction

Historical Context:

The Kawasaki Z250 and KZ305 models were part of Kawasaki's popular 'Z' series, offering a blend of performance and reliability in the lightweight to middleweight motorcycle segment during the late 1970s and early 1980s. They appealed to a broad range of riders, from commuters to enthusiasts seeking an accessible sporting motorcycle.

Key Competitors:

Competed with models from Honda (CB series), Yamaha (XS series), and Suzuki (GS series) in the 250cc and 305cc classes.

Versatility:

These motorcycles were known for their versatility, suitable for daily commuting, weekend rides, and light touring.

Engineering:

Benefited from Kawasaki's established reputation for robust engineering and performance-oriented designs.

Diy Support:

Provides the essential information for owners and mechanics to perform maintenance, repairs, and diagnostics, enabling significant cost savings and extending the lifespan of these classic motorcycles.

📋 Manual Details

Primary Coverage:

Workshop Service Repair

Secondary Coverage:

Maintenance, Troubleshooting, Adjustments, Disassembly, Assembly, Specifications, Appendices, Supplements

Estimated Page Count:

Varies based on specific edition, typically 300-500 pages for comprehensive coverage

Manual Type:

Factory Authorized Service Manual / Workshop Manual

Language:

English

File Format:

PDF

Digital Compatibility:

Windows, MacOS

📖 Manual Coverage

Engine Systems:

Engine disassembly/assembly, piston, rings, cylinder, crankshaft, camshaft, valve timing, lubrication system, cooling system (air-cooled), carburetor(s) (Keihin, Mikuni models), ignition system (CDI, points), starting system.

Transmission Drivetrain:

Clutch operation, gearbox inspection and repair, gear ratios, chain drive maintenance, rear differential (if applicable to specific sub-models).

Chassis Suspension:

Front fork (telescopic), rear suspension (swingarm, shock absorber(s)), frame inspection, steering head bearing service.

Braking System:

Front and rear brake inspection, adjustment, hydraulic systems (if applicable), brake pad/shoe replacement, master cylinder and caliper service.

Electrical System:

Wiring diagrams, lighting system, charging system (alternator, rectifier/regulator), battery, starter motor, ignition system troubleshooting, instrumentation.

Fuel System:

Fuel tank, fuel lines, fuel filter, carburetor tuning and overhaul.

Exhaust System:

Exhaust pipe inspection, muffler maintenance, gasket replacement.

Bodywork Controls:

Handlebars, levers, cables, seat, body panels, footpegs, fenders.

Maintenance Procedures:

Oil changes, filter replacement, spark plug service, air filter cleaning/replacement, chain lubrication and adjustment, brake adjustment, cable lubrication, battery testing, general lubrication points.

Diagnostic Procedures:

Troubleshooting guides for common starting, running, electrical, and performance issues, fault finding based on symptoms.

Repair Procedures:

Step-by-step instructions for engine rebuilds, transmission repairs, suspension overhauls, electrical component replacement, brake system servicing, carburetor rebuilds.

Adjustment Procedures:

Carburetor synchronization and jetting, ignition timing, valve clearance adjustment, clutch and throttle cable free play adjustment, suspension settings.

Disassembly Assembly:

Detailed instructions for removing and reinstalling major components and sub-assemblies.

Depth Level:

Comprehensive (covering from basic maintenance to complete engine rebuilds and complex electrical diagnostics)

Diagrams Illustrations:

Detailed exploded diagrams, schematic diagrams, and illustrative photos/drawings for procedures.

Specifications Data:

Precise torque values, tolerances, clearances, fluid capacities, electrical specifications (resistance, voltage), performance data.

📊 Manual Specifications

File Format Detail:

PDF (Portable Document Format)

Searchability:

Searchable text content for quick information retrieval.

Print Quality:

High resolution, suitable for printing individual pages or the entire manual.

Image Clarity:

Clear and legible diagrams, illustrations, and text.

Binding Type:

Digital PDF (no physical binding)

Paper Type:

N/A (Digital format)

⚙️ Engine Specifications

Engine Type:

Four-stroke, parallel-twin (most common configurations)

Displacement:

249cc (Z250), 305cc (KZ305)

Bore X Stroke:

Varies by specific model and engine code, e.g., Z250 might have ~54.0 mm x 54.4 mm

Compression Ratio:

Typically around 9.0:1 to 10.0:1

Valve Train:

DOHC (Double Overhead Camshaft) or SOHC (Single Overhead Camshaft), 2 valves per cylinder

Horsepower:

Approximately 27-33 HP (depending on specific model and tuning)

Torque:

Approximately 19-23 lb-ft (depending on specific model and tuning)

Carburetor Type:

Single or dual Keihin or Mikuni carburetors (e.g., VM24, PD26)

Fuel Capacity:

Approximately 10-12 liters (2.6-3.2 US gallons)

Fuel Type:

Unleaded gasoline, octane rating specified in manual

Oil Type:

API SE/SF classification 10W-40 or 20W-50 motorcycle specific oil (refer to manual for exact specification)

Oil Capacity:

Approximately 1.4-1.8 liters (with filter change)

Ignition Type:

CDI (Capacitor Discharge Ignition) or Breaker Point Ignition (depending on model variant)

Spark Plugs:

NGK B8ES, ND X24ES-U or equivalent (refer to manual for exact specification)

🔧 Transmission

Transmission Type:

6-speed constant mesh manual transmission

Optional Transmission:

N/A (Standard manual transmission)

Clutch Type:

Wet, multiple-disc clutch

Final Drive:

Chain drive

Transmission Oil Type:

API GL-4, SAE 80 or 85W hypoid gear oil (refer to manual)

📐 Dimensions

Overall Length:

Varies by model, e.g., ~2040-2120 mm (80.3-83.5 in)

Overall Width:

Varies by model, e.g., ~750-800 mm (29.5-31.5 in)

Overall Height:

Varies by model, e.g., ~1080-1150 mm (42.5-45.3 in)

Wheelbase:

Varies by model, e.g., ~1370-1400 mm (53.9-55.1 in)

Dry Weight:

Approximately 150-165 kg (330-364 lbs)

Wet Weight:

Approximately 160-175 kg (353-386 lbs) (with all fluids)

Max Load Capacity:

Refer to specific model specifications in manual

Front Tire Size:

Typically 3.00-18 or 3.25-18

Rear Tire Size:

Typically 3.50-18 or 3.75-18

Front Wheel:

Spoked, typically 18-inch diameter

Rear Wheel:

Spoked, typically 18-inch diameter

🛡️ Safety Features

Safety Ratings:

Motorcycles of this era were not subject to standardized crash testing like modern cars. Safety features are primarily inherent design elements and rider responsibility.

Braking System Design:

Front disc brake (common on many models) and rear drum brake, providing adequate stopping power for the era.

Suspension Handling:

Telescopic front forks and adjustable rear suspension contribute to stable handling and rider control.

Lighting:

Headlight, taillight, turn signals, and brake light for visibility.

Frame Construction:

Steel frame designed for structural integrity and rider support.

💡 Technology Features

Infotainment System:

N/A (Basic motorcycle technology of the era)

Driver Assistance Features:

N/A

Connectivity Features:

N/A

Instrument Cluster:

Analog speedometer, tachometer (on most models), odometer, trip meter, neutral indicator, high beam indicator, turn signal indicators.

🔧 Maintenance

Oil Change Interval:

Typically every 3,000-5,000 km (1,800-3,000 miles) or 6 months, whichever comes first. Refer to manual for exact mileage.

Air Filter Service:

Clean every 3,000-6,000 km (1,800-3,700 miles), replace as needed. Check more frequently in dusty conditions.

Spark Plug Service:

Inspect and clean every 5,000-10,000 km (3,000-6,000 miles), replace as needed. Refer to manual for specific plug gap.

Chain Maintenance:

Lubricate every 1,000 km (600 miles) or after riding in rain. Adjust tension every 1,000-2,000 km (600-1,200 miles) as per manual specification.

Valve Clearance Check:

Typically at 10,000-20,000 km (6,000-12,000 miles) or as specified in the manual.

Engine Oil Grade:

10W-40, 20W-50 (Motorcycle specific, API SE/SF or higher)

Brake Fluid Type:

DOT 3 or DOT 4 (if hydraulic, check manual for specific requirement)

Fork Oil Type:

Typically SAE 10W or 15W fork oil (refer to manual for type and quantity)

Carburetor Issues:

Clogged jets, vacuum leaks, float level issues leading to poor idling or performance. Diaphragm wear on some models.

Electrical Issues:

Corroded connections, failing rectifier/regulator, weak charging system, CDI unit failure (less common).

Fuel System Issues:

Petcock leaks, fuel line degradation, carburetor float bowl drain issues.

Engine Wear:

Cam chain tensioner wear, piston ring wear, valve seat wear due to age and mileage.

Suspension Wear:

Worn fork seals, degraded fork oil, worn rear shock absorber bushings/seals.

📚 Vehicle History

Kawasaki Legacy:

Kawasaki Heavy Industries has a long and storied history in motorcycle manufacturing, known for innovation, performance, and durability across various engine displacements and styles.

Z Series Introduction:

The 'Z' designation for Kawasaki motorcycles dates back to the 1970s with iconic models like the Z1. The Z250 and KZ305 built upon this legacy, adapting to market trends and technological advancements of the late 70s and early 80s.

Production Period:

The specific models covered by this manual were primarily produced and sold between 1979 and 1982, representing a distinct generation of Kawasaki's parallel-twin motorcycles.

Manufacturing Location:

Primarily Japan

🏆 Awards & Recognition

Model Awards:

While specific awards for these individual models are not widely documented, Kawasaki's parallel-twin motorcycles of this period were generally well-regarded for their performance, reliability, and value, contributing to Kawasaki's strong market presence.