Segment:
Dual-purpose motorcycle, often referred to as a 'Dual Sport' or 'Enduro' style bike.
Competitors 1987:
Honda NX250, Kawasaki KLR250, Suzuki DR250S.
Intended Use:
Versatile on-road and off-road capability, commuting, light trail riding, adventure touring.
Target Audience:
Riders seeking a reliable and capable all-around motorcycle for varied terrain and commuting needs.
Manual Value:
Provides comprehensive technical guidance to maintain, repair, and restore the Yamaha BR250F, ensuring longevity and optimal performance.
Engine:
Complete engine overhaul, disassembly, inspection, assembly, tuning, lubrication system, cooling system (air-cooled), fuel system (carburetor), ignition system, exhaust system.
Transmission:
Gearbox disassembly, inspection, assembly, gear shift mechanism, clutch operation and adjustment.
Drivetrain:
Drive chain adjustment and maintenance, rear hub, sprockets.
Suspension:
Front fork disassembly, inspection, seal replacement, oil levels, rear shock absorber inspection and replacement, swingarm maintenance.
Brakes:
Front and rear brake system maintenance, fluid replacement, bleeding, caliper inspection, brake pad replacement, drum brake adjustment.
Electrical System:
Wiring diagrams, battery maintenance, charging system (stator, regulator/rectifier), lighting system (headlight, taillight, indicators), ignition system troubleshooting, starter motor, horn.
Fuel System:
Carburetor disassembly, cleaning, adjustment, jetting specifications, fuel tank maintenance, fuel lines.
Body And Frame:
Frame inspection, body panel removal and installation, seat, handlebars, controls, footpegs, fenders.
Wheels And Tires:
Tire pressure specifications, wheel bearing maintenance, spoke tension adjustment, rim inspection.
Maintenance:
Regular scheduled maintenance, oil changes, filter replacements, chain lubrication and adjustment, spark plug replacement, air filter cleaning/replacement, brake system checks.
Troubleshooting:
Diagnostic procedures for common problems, electrical system faults, engine performance issues, starting problems, transmission issues.
Repair:
Detailed step-by-step instructions for component disassembly, repair, reassembly, and adjustment for all major vehicle systems.
Rebuild:
Comprehensive guides for engine, carburetor, and suspension component rebuilds.
Specifications And Data:
Torque specifications, tolerances, fluid capacities, wiring diagrams, electrical component data, part numbers (where applicable).
Depth Of Coverage:
Comprehensive: Covers all aspects from basic owner maintenance to advanced mechanical and electrical repair, suitable for professional mechanics and experienced DIY enthusiasts.
Engine Type:
Four-stroke, single-cylinder, DOHC, 4 valves
Displacement:
249 cc (249.6cc is common for this engine)
Bore X Stroke:
72.0 mm x 61.2 mm (typical for this engine)
Compression Ratio:
9.7:1 (typical)
Cooling System:
Air-cooled
Horsepower Estimated:
Approximately 24-28 hp @ 8000 rpm (varies by market and tuning)
Torque Estimated:
Approximately 20-23 Nm @ 6500 rpm (varies by market and tuning)
Carburetor Type:
Mikuni VM34SS or similar 34mm constant velocity carburetor
Fuel Type:
Unleaded gasoline, octane rating 87 or higher (RON/MON specified in manual)
Ignition Type:
CDI (Capacitor Discharge Ignition)
Oil Type:
Yamalube 4 (or equivalent API SE, SF, SG 10W-40 or 20W-50 motorcycle oil)
Oil Capacity:
Approx. 1.7 - 1.9 Liters (with filter change)
Starter Type:
Electric Start
Transmission Type:
6-speed constant mesh
Clutch Type:
Wet, multi-plate
Gear Ratios:
Specific gear ratios provided in the manual (e.g., 1st: 2.833, 2nd: 1.933, 3rd: 1.478, 4th: 1.200, 5th: 1.045, 6th: 0.917)
Final Drive:
O-ring sealed chain
Transmission Oil Type:
Yamalube 4 (or equivalent API SE, SF, SG 10W-40 or 20W-50 motorcycle oil)
Transmission Oil Capacity:
Approx. 0.9 Liters
Safety Certifications:
N/A (Motorcycle safety certifications vary by region and are generally not categorized like automotive safety ratings).
Braking System:
Front: Disc brake; Rear: Drum brake.
Lighting:
Halogen headlight, taillight, brake light, turn signals.
Frame Construction:
Steel semi-double cradle frame for stability and durability.
Ergonomics:
Upright riding position for rider comfort and control.
Infotainment Features:
N/A (Focus is on mechanical and electrical function, no infotainment systems).
Driver Assistance Features:
N/A (No electronic driver assistance systems present).
Connectivity Features:
N/A (No connectivity features).
Instrument Panel:
Analog speedometer, tachometer, odometer, trip meter, indicator lights (neutral, oil pressure, turn signals, high beam).
Oil Change Interval:
Every 3,000-5,000 km or annually (refer to manual for exact intervals based on usage).
Air Filter Cleaning:
Every 1,000-2,000 km or more frequently in dusty conditions.
Spark Plug Replacement:
Every 10,000-15,000 km.
Valve Clearance Check:
Every 5,000-10,000 km (crucial for DOHC engines).
Chain Maintenance:
Lubricate and adjust every 500-1,000 km, inspect for wear.
Brake Fluid Type:
DOT 3 or DOT 4 (refer to manual for specific type and replacement interval).
Coolant Type:
N/A (Air-cooled engine)
Common Wear Items:
Clutch plates, brake pads/shoes, swingarm bushings, fork seals, carburetor diaphragms, charging system components (regulator/rectifier).
Potential Faults:
Carburetor gumming due to infrequent use, electrical connector corrosion, ignition coil failure.
Typical Spark Plug:
NGK CR9E or equivalent (verify with manual).
Typical Oil Filter:
If applicable, would be a cartridge type or internal screen (verify with manual).
Yamaha Motorcycles:
Yamaha Motor Corporation, established in 1955, is a leading manufacturer of motorcycles, marine products, and other motorized vehicles, known for innovation and performance.
Br250F Lineage:
Part of Yamaha's range of versatile dual-purpose motorcycles, building on smaller displacement enduro and trial bikes. The BR250F likely succeeded earlier models and was part of a generation of 250cc dual-sports.
Production Years Estimate:
Mid-to-late 1980s (specific production range to be confirmed by internal Yamaha data).
Manufacturing Location:
Japan (typical for Yamaha motorcycles of this era).
