Market Segment:
Lightweight British motorcycle, popular for everyday use and clubman racing in its era.
Competitors:
Competed against other British 250cc offerings from manufacturers like BSA (e.g., C15), Triumph (e.g., Cub), and Royal Enfield.
Key Features:
Known for its robust construction, relatively simple mechanics, and usability as a daily rider.
Covered Years:
1958, 1959, 1960, 1961, 1962, 1963, 1964
Manual Type:
Workshop Service Repair Manual
Engine:
Detailed coverage of the 250cc engine, including disassembly, assembly, inspection, and adjustment procedures.
Transmission:
Information on gearbox maintenance, repair, and adjustment.
Electrical System:
Diagnosis, testing, and repair of the motorcycle's electrical components, including lighting, ignition, and charging systems.
Chassis And Suspension:
Coverage of frame, forks, shock absorbers, and wheel assembly.
Brakes:
Details on front and rear brake system maintenance and repair.
Fuel System:
Carburetor adjustment, cleaning, and fuel tank/lines maintenance.
Bodywork And Trim:
Covers removal, installation, and basic repair of fenders, fuel tank, and seat.
Lighting And Signals:
Covers maintenance and repair of headlights, taillights, and turn signals (if equipped).
Routine Maintenance:
Scheduled maintenance tasks, lubrication, and general upkeep.
Troubleshooting:
Systematic diagnostic procedures for identifying and resolving common problems.
Repair And Rebuild:
Step-by-step instructions for component disassembly, overhaul, and reassembly.
Adjustments:
Detailed guidance on making necessary adjustments to various motorcycle systems.
Installation And Removal:
Instructions for removing and reinstalling major components and parts.
Tightening Torques:
Provides specific torque values for critical fasteners, ensuring correct assembly and preventing damage.
Troubleshooting Charts:
Diagnostic flowcharts or tables to assist in pinpointing issues.
Technical Depth:
Comprehensive, covering everything from basic adjustments to full engine rebuilds and detailed diagnostics.
Pictorial Diagrams:
Includes pictorial diagrams, exploded diagrams, drawings, and photos to guide repairs.
Service Tools:
References special service tool numbers and illustrates their usage.
Wear Limits:
Includes wear limits for components, essential for determining serviceability.
Completeness:
100% complete and intact, no missing or corrupt pages/sections.
Engine Type:
Single-cylinder, four-stroke OHV (Overhead Valve)
Displacement:
Approximately 250cc (exact bore and stroke would be detailed in the manual)
Bore X Stroke:
Specific bore and stroke dimensions would be detailed for engine calculations.
Compression Ratio:
Compression ratio specifications for optimal performance and engine health.
Horsepower:
Typically in the range of 15-20 bhp (specific figures available in manual)
Torque:
Torque figures and power curves would be detailed in the manual for optimal tuning.
Carburetor:
Likely a single Amal or similar British carburetor (specific model and jetting details in manual).
Fuel Type:
Leaded gasoline (typical for the era), specific octane rating in manual.
Transmission Type:
Constant mesh, four-speed gearbox
Optional Gearboxes:
Not typically applicable to this model; standard transmission is the focus.
Clutch:
Wet multi-plate clutch (details on operation and maintenance in manual).
Gear Ratios:
Specific gear ratios for each of the four speeds would be provided in the manual.
Safety Ratings:
Safety ratings for motorcycles of this era were not standardized as they are today; emphasis is on mechanical integrity and rider caution.
Active Safety:
Effective braking, responsive steering, and good visibility are key active safety aspects. Manual covers their maintenance.
Passive Safety:
Robust frame construction. The manual's emphasis on correct assembly and adjustment contributes to passive safety.
Oil Change Interval:
Specific mileage/time intervals for oil changes would be provided in the manual's periodic maintenance chart.
Tune Up Interval:
Details on recommended intervals for carburetor adjustment, ignition timing checks, and valve clearance adjustments are crucial and included.
Chain Adjustment Interval:
Recommendations for chain tension adjustment and lubrication.
Engine Oil Type:
Specific viscosity grade (e.g., SAE 20W/50) and type (e.g., motorcycle-specific, not car oil with friction modifiers) would be listed.
Gearbox Oil Type:
Specific type and quantity of gearbox oil would be detailed in the manual.
Fork Oil Type:
Specific type and quantity of fork oil would be listed for proper suspension function.
Common Wear Items:
The manual would cover the inspection and replacement of common wear items such as piston rings, valve guides, clutch plates, and chain/sprockets.
Electrical Gremlins:
Potential for aging wiring harnesses, stator, and rectifier issues would be addressed through diagnostic procedures.
Carburetor Tuning:
The manual provides essential guidance for maintaining optimal carburetor performance, a common point of attention on vintage bikes.
Ignition Timing:
Crucial details on setting and checking ignition timing for correct engine operation.
Manufacturer:
Associated with Associated Motorcycles (AMC) group, which also produced Norton and Matchless motorcycles.
Model Lineage:
The 'Lightweight' designation points to a focus on ease of handling and affordability within AJS's broader model range.
Engine Variants:
While the manual specifies '250cc', potential minor variations in engine tuning or component suppliers over the years are implicitly covered.
Manufacturing Location:
United Kingdom
