Positioning:
The BSA Bantam D14/4 represents an accessible and popular entry-level motorcycle from the mid-1960s, known for its simplicity and usability. This manual targets owners and enthusiasts looking to maintain and repair these classic British lightweight motorcycles.
Competitors:
Competed with other 175cc two-stroke motorcycles from manufacturers like Triumph (Tigercub derivatives), James, Francis-Barnett, and various European marques.
Vehicle Appeal:
Lightweight, economical, easy to ride and maintain, classic British styling, good parts availability for common items.
Coverage Summary:
Comprehensive service, repair, and workshop procedures for BSA Bantam D14/4 models, including Supreme and Sports variants.
Estimated Page Count:
Approximately 150-250 pages (typical for this era of workshop manual)
Type:
Workshop Service Repair Manual
Format:
Likely printed reproduction or potentially digital (PDF)
Engine Systems:
Engine assembly, disassembly, tuning, carburetor settings, ignition system, lubrication, cooling (air-cooled).
Transmission Systems:
Gearbox overhaul, clutch operation and adjustment, gear change mechanism.
Chassis Systems:
Frame, front forks (suspension), rear suspension, wheels, brakes (drum), steering.
Electrical Systems:
Wiring diagrams, lighting, charging system (dynamo/alternator), ignition coil, points, condenser.
Fuel System:
Fuel tank, fuel lines, fuel tap, Amal carburetor (likely models).
Bodywork:
Fenders, fuel tank, seat, controls, basic body component removal/installation.
Routine Maintenance:
Lubrication points, chain adjustment, brake adjustment, spark plug replacement, air filter cleaning/replacement.
Troubleshooting:
Diagnosing common running issues, ignition problems, fueling problems, mechanical noises.
Overhaul Procedures:
Complete engine rebuild, gearbox rebuild, suspension component overhaul, brake system refurbishment.
Special Procedures:
Valve clearance adjustment, timing setup, specific tool usage.
Depth:
Detailed mechanical repair and overhaul procedures suitable for home mechanics and professional workshops.
Digital Format:
If digital, likely PDF with OCR for searchability. Print quality of reproductions can vary.
Print Quality:
Reproduction print quality is generally good for clarity, though original scans may have imperfections.
Binding:
Typically saddle-stitched or perfect bound for printed versions.
Paper Quality:
Standard paper stock, often with glossy pages for diagrams in original manuals.
Type:
Two-stroke, air-cooled, piston-ported single-cylinder
Displacement:
174cc (175cc class)
Bore X Stroke:
Approximately 61.5mm x 59mm (specifics may vary slightly)
Compression Ratio:
Typically around 7.0:1 to 7.5:1
Power Output:
Around 10-12 bhp at 5000-5500 rpm (depending on specific model and state of tune)
Torque:
Approximately 12-14 lb-ft (specific figures vary)
Carburetor:
Likely Amal concentric or Monobloc, e.g., 20mm or 22mm bore. Manual will detail specific jetting and settings.
Fuel Type:
Leaded gasoline with appropriate two-stroke oil mix (e.g., 20:1 or 25:1, manual will specify).
Type:
Coil and points, magneto or dynamo ignition depending on exact year and specification.
System:
Total loss oiling system via pre-mix in fuel. Gearbox oil fill.
Type:
Four-speed constant mesh, foot-shift
Clutch:
Wet multi-plate clutch, operated by cable.
Gearbox Oil:
Specific gearbox oil, typically SAE 30 or SAE 90. Manual will detail type and capacity.
Wheelbase:
Approximately 52-53 inches (1320-1345 mm)
Seat Height:
Approximately 30-31 inches (760-790 mm)
Dry Weight:
Around 220-240 lbs (100-110 kg), depending on model variant.
Fuel Capacity:
Approximately 2.5-3 imperial gallons (11.4-13.6 liters).
Oil Capacity:
Gearbox: approx. 0.5 pint (0.28 liters). Total loss system means oil is mixed with fuel.
Safety Standards:
As per 1960s British motorcycle manufacturing standards. Not subject to modern crash testing protocols.
Braking System:
Full width drum brakes front and rear. Manual covers adjustment and relining.
Lighting:
Headlamp, tail lamp, brake light, indicators (optional on some models). Wiring diagrams included.
Features:
None (analog instrument cluster: speedometer, possibly ammeter).
Features:
None (mechanical controls: throttle, clutch, brake levers, gear shift).
Features:
None (purely mechanical operation).
Oil Change Gearbox:
Every 3,000-4,000 miles or annually. Manual will provide specific intervals.
Spark Plug Check:
Every 1,000-2,000 miles. Manual details gap and type.
Chain Lubrication Adjustment:
Every 300-500 miles, or after riding in wet conditions.
Ignition Timing Check:
As needed, or at major service intervals. Manual provides timing marks and procedures.
Engine Oil Mix:
Refer to manual for specific 2T oil ratio (e.g., Castrol R40 or equivalent mineral-based 2T oil at 20:1 or 25:1).
Gearbox Oil Type:
API GL-3 or GL-4 SAE 30 or SAE 90 gear oil (check manual for precise recommendation).
Brake Fluid:
Not applicable for typical drum brake systems of this era, though cable lubrication is important.
Ignition Points:
Wear and pitting of contact points in the distributor/points assembly, requiring cleaning or replacement.
Carburetor Tuning:
Amal carburetors can be sensitive to wear and require precise adjustment of jetting and needle settings for optimal performance.
Gaskets Seals:
Aging rubber seals and gaskets can lead to oil and fuel leaks. Manual will detail replacement procedures.
Electrical Connections:
Corrosion and looseness in electrical connections, especially on older models, can cause intermittent issues.
Manufacturer:
Burman & Sons (BSA) - Birmingham Small Arms Company, a renowned British manufacturer of motorcycles, bicycles, and firearms.
Bantam Lineage:
The Bantam was BSA's long-running line of lightweight, affordable two-stroke motorcycles, first introduced in the 1940s and evolving through numerous models and engine sizes. The D14/4 is part of the later generation, representing a refined design from the mid-1960s.
Production Period:
The D14/4 model was produced in the mid to late 1960s, around 1965-1968.
Manufacturing Location:
United Kingdom
