Target Audience:
AJS Owners, Restorers, Vintage Motorcycle Enthusiasts, Specialist Mechanics.
Value Proposition:
Provides essential technical data and repair procedures for a specific era of British motorcycle, crucial for maintaining these classic machines.
Documentation Source:
Likely compiled from original factory service bulletins and workshop manuals, offering authoritative guidance.
Practicality:
Designed for practical application in a workshop setting, offering solutions to common problems encountered with these models.
Engine Details:
Detailed coverage of single-cylinder AJS engines, including overhaul, tuning, and component identification. Specifics on carburetor adjustment (e.g., Amal), ignition timing, valve clearances, and lubrication systems.
Transmission Details:
Covers gearbox disassembly, assembly, gear selection mechanisms, clutch operation, and lubrication for both pre-unit and unit construction transmissions where applicable across the model range.
Electrical System Details:
Wiring diagrams for lighting, ignition, and charging systems. Troubleshooting common electrical faults, generator/dynamo maintenance, battery care, and magneto ignition servicing.
Chassis And Suspension Details:
Information on frame inspection, steering head bearing adjustment, front fork servicing (including plunger and telescopic types), rear suspension components (shock absorbers, bushings), and wheel bearing maintenance.
Braking System Details:
Maintenance and adjustment of drum brakes, including brake shoe replacement, cable adjustment, and linkage lubrication. Information on brake rod systems.
Major Rebuilds:
Comprehensive step-by-step guides for complete engine and gearbox overhauls, including piston and con-rod replacement, crankshaft balancing, and gearbox rebuilds.
Routine Maintenance:
Detailed schedules and procedures for oil changes, filter cleaning/replacement, spark plug servicing, chain adjustment, lubrication points, and tire pressure checks.
Diagnostics:
Troubleshooting charts and symptom-based diagnostic procedures for common running issues, ignition problems, and mechanical faults.
Component Overhaul:
Specific instructions for overhauling carburetors (e.g., Amal concentric and Monobloc), magnetos, dynamos, and other key components.
Depth Level:
In-depth workshop level, suitable for experienced mechanics and enthusiasts undertaking full restorations and repairs.
Precision Specs:
Includes critical tolerances, clearances, torque settings, and specifications for engine components, bearings, and fasteners.
Paper Quality:
Durable, high-quality paper stock suitable for workshop environments.
Print Clarity:
Sharp, clear text and line drawings/diagrams.
Binding:
Stitched or bound for durability, allowing flat opening.
Engine Type:
Single Cylinder, Four-Stroke, Air-Cooled
Common Displacements:
Typically 250cc, 350cc, and 500cc variants (e.g., AJS Model 18S 500cc, AJS Model 14 250cc, AJS Model 30/31 350cc).
Horsepower Range:
Varies by displacement, generally 15-30 bhp.
Torque Characteristics:
Emphasis on low to mid-range torque for usability.
Carburetor Types:
Primarily Amal concentric and Monobloc carburetors. Manual provides tuning and rebuilding guidance for these.
Ignition Type:
Magneto ignition (e.g., Lucas, BTH) for most models, with some later models potentially having coil ignition. Manual covers magneto timing and maintenance.
Oil System:
Total Loss or Pump-driven oil systems depending on the specific model variant and year. Manual details oil capacities and recommended oil types.
Type:
Manual, constant-mesh gearboxes, typically 3 or 4-speed.
Features:
Some models may have been fitted with alternative gearboxes or were available with different ratios from new.
Clutch Type:
Dry multi-plate or single plate clutch, depending on the model. Manual details adjustment and maintenance.
Era Context:
Safety features commensurate with the post-war era; no modern safety ratings apply.
Braking Effectiveness:
Drum brakes front and rear. Manual provides maintenance to ensure optimal, albeit basic, stopping power for the era.
Lighting:
Lucas or similar lighting systems. Manual covers bulb types and maintenance.
Oil Change:
Typically every 1000-1500 miles, or as specified for the lubrication system type.
Valve Clearance Check:
Recommended every 2000-3000 miles, or as performance dictates.
Spark Plug Service:
Regular inspection and cleaning/replacement as per manual recommendations.
Chain Lubrication Adjustment:
Frequent checking and lubrication, especially if exposed chain guards are not fitted.
Engine Oil Type:
For total loss systems: Castrol XL or similar (non-detergent, SAE 20W or 30). For pump systems: SAE 20W/50 or 20W/50 motorcycle-specific oil. Manual will specify exact grades.
Gearbox Oil:
EP90 or equivalent gear oil. Capacity varies, typically 0.5-1 pint.
Fork Oil:
Lightweight fork oil, SAE 10W or equivalent. Manual specifies type and quantity per fork leg.
Ignition Reliability:
Magneto wear, points fouling, and weak spark can be common. Manual provides troubleshooting.
Oil Leaks:
Worn seals and gaskets can lead to oil leaks, particularly around the pushrod tubes and crankcases.
Carburetor Tuning:
Amal carburetors can be sensitive to altitude, temperature, and wear. Proper tuning is essential for smooth running.
Transmission Wear:
Wear on dog teeth and selector mechanisms can lead to false neutrals or difficult gear changes.
Manufacturer:
Associated Motorcycles (AMC) Group, Manchester, UK.
Reputation:
Known for producing robust and reliable British motorcycles, particularly successful in trials and scrambles.
Development:
The Singles range evolved from pre-war designs, incorporating telescopic front forks and plunger rear suspension as standards in this period. Key models include the Model 18S (500cc), Model 14 (250cc), and 350cc variants.
Production Period:
1948-1957 covers a significant period of AJS's single-cylinder production before further model changes and eventual absorption into Norton Villiers.