Market Position:
        
        
            The Yamaha Majesty Skyliner is a popular mid-size scooter, known for its comfortable ride, practicality, and fuel efficiency, targeting urban commuters and leisure riders. This manual serves essential support for maintenance and repair.
        
     
    
    
        
            Model Evolution:
        
        
            The Majesty series has a long lineage, with the Skyliner being a significant iteration. The YP125/YP150 likely represents a specific generation or update, focusing on engine refinement and chassis improvements over earlier models. This manual would cover specific technical details relevant to this generation.
        
     
    
    
        
            Key Features Of Manual:
        
        
            Provides in-depth technical data, diagnostic procedures, and repair instructions crucial for maintaining the performance, reliability, and longevity of the Yamaha Majesty Skyliner YP125/YP150.
        
     
 
    
    
    
        
            Systems Covered:
        
        
            
                        
                            • Engine Overhaul and Reassembly
                        
                        
                            • Fuel System (including Carburetor adjustments/cleaning)
                        
                        
                            • Cooling System Diagnosis and Repair
                        
                        
                            • Ignition System
                        
                        
                            • Starting System
                        
                        
                            • Charging System
                        
                        
                            • Lighting System
                        
                        
                            • Instrumentation
                        
                        
                            • Suspension (Front and Rear)
                        
                        
                            • Braking System (Front and Rear)
                        
                        
                            • Steering System
                        
                        
                            • Frame and Bodywork
                        
                        
                            • Wheels and Tires
                        
                        
                            • Drive System (V-belt, etc.)
                        
                        
                            • Lubrication System
                        
 
         
     
    
        
            Electrical Diagrams:
        
        
            Comprehensive wiring diagrams for all electrical circuits, including charging, ignition, lighting, starting, and accessories, aiding in fault diagnosis.
        
     
    
        
            Frame And Bodywork:
        
        
            Includes procedures for body panel removal, fairing inspection, seat removal, and general chassis component checks.
        
     
    
    
        
            Procedures Included:
        
        
            
                        
                            • Routine Maintenance Schedules
                        
                        
                            • Component Inspection and Adjustment
                        
                        
                            • Disassembly and Reassembly Procedures
                        
                        
                            • Troubleshooting Guides for Common Faults
                        
                        
                            • Torque Specifications
                        
                        
                            • Clearance Measurements
                        
                        
                            • Diagnostic Procedures
                        
                        
                            • Wiring Diagrams
                        
                        
                            • Component Specifications
                        
 
         
     
    
        
            Rebuild Instructions:
        
        
            Complete instructions for engine teardown, inspection of components (pistons, cylinders, crankshaft, valves), and reassembly with correct tolerances and torque settings.
        
     
    
        
            Suspension Adjustment:
        
        
            Procedures for adjusting rear shock absorber preload if applicable, and inspection/service for front forks.
        
     
    
    
        
            Technical Depth:
        
        
            Comprehensive service and repair information, suitable for qualified technicians and experienced DIY mechanics. Covers diagnostics, repairs, and adjustments beyond basic owner's manual level.
        
     
    
    
        
            Diagnostic Procedures:
        
        
            Detailed step-by-step troubleshooting guides for identifying and resolving mechanical and electrical faults, including fault codes if applicable.
        
     
 
    
    
    
        
            Binding Type:
        
        
            Likely perfect bound or spiral bound for durability in a workshop environment.
        
     
    
        
            Paper Type:
        
        
            Durable, possibly semi-gloss paper to withstand workshop conditions and frequent handling.
        
     
    
    
        
            File Format:
        
        
            Not specified, but typically PDF for digital versions or printed book.
        
     
 
    
    
    
        
            Primary Engine Type:
        
        
            4-stroke, Liquid-cooled, SOHC, 4-valve
        
     
    
        
            Bore X Stroke:
        
        
            YP125: 52.0 x 58.0 mm, YP150: 57.3 x 57.9 mm (typical for these displacements, manual will confirm exact figures)
        
     
    
        
            Displacement:
        
        
            YP125: 125cc class, YP150: 150cc class (specific figures to be detailed in manual)
        
     
    
        
            Compression Ratio:
        
        
            To be specified in manual, typically around 11.0:1 to 12.0:1 for modern 4-stroke scooters.
        
     
    
        
            Engine Mounting:
        
        
            The engine is typically a stressed member of the chassis, mounted to the frame via a swingarm.
        
     
    
    
        
            Max Power:
        
        
            YP125: Approx. 10-11 kW (13-15 hp) @ 7500-8000 rpm; YP150: Approx. 11-13 kW (15-17 hp) @ 7000-7500 rpm (specifications vary by market and tuning, manual will provide exact figure).
        
     
    
        
            Max Torque:
        
        
            YP125: Approx. 12-13 Nm @ 6000-6500 rpm; YP150: Approx. 14-15 Nm @ 5500-6000 rpm (specifications vary by market and tuning, manual will provide exact figure).
        
     
    
    
        
            Fuel System Type:
        
        
            Carburetor (Mikuni or Keihin likely) for YP125/YP150 models covered by this manual. Later models might feature Fuel Injection, but this manual's scope suggests carburetor.
        
     
    
        
            Carburetor Type:
        
        
            Specific model number (e.g., VM26, BD26A) and settings will be detailed in the manual.
        
     
    
        
            Fuel Tank Capacity:
        
        
            Approx. 10-12 Liters. Manual will confirm exact capacity and recommended fuel grade (e.g., Unleaded gasoline 95 RON).
        
     
    
    
        
            Oil Type:
        
        
            Yamaha recommends specific grades, likely Yamalube 4T mineral or semi-synthetic SAE 10W-40 or 20W-40. Manual will specify exact Yamaha standard and viscosity.
        
     
    
        
            Oil Capacity:
        
        
            Approx. 0.8 - 1.0 Liters for oil change, possibly with filter change. Manual will state exact figures for dry fill and oil change.
        
     
    
    
        
            Cooling System:
        
        
            Liquid-cooled
        
     
    
        
            Coolant Type:
        
        
            Yamaha's specific coolant or a high-quality ethylene glycol-based antifreeze with corrosion inhibitors. Manual will specify the Yamaha standard and mixture ratio (typically 50/50).
        
     
 
    
    
    
        
            Transmission Type:
        
        
            Automatic, V-belt CVT (Continuously Variable Transmission)
        
     
    
    
        
            Final Drive:
        
        
            Gear reduction via drive shaft and final gears.
        
     
    
    
        
            Transmission Fluid Type:
        
        
            Yamalube Gear Oil or equivalent, specific viscosity (e.g., SAE 80 or 85W-90). Manual will confirm type and capacity.
        
     
 
    
    
    
        
            Overall Length:
        
        
            Approximately 2000-2100 mm (specific to model variant, manual will confirm).
        
     
    
        
            Overall Width:
        
        
            Approximately 750-800 mm (specific to model variant, manual will confirm).
        
     
    
        
            Overall Height:
        
        
            Approximately 1300-1400 mm (specific to model variant, manual will confirm).
        
     
    
    
        
            Dry Weight:
        
        
            Approximately 140-155 kg (specific to model variant, manual will confirm).
        
     
    
        
            Wet Weight:
        
        
            Approximately 150-165 kg (specific to model variant, manual will confirm).
        
     
    
    
        
            Front Tire Size:
        
        
            Typically 120/70-14 or similar. Manual will specify exact size and pressure.
        
     
    
        
            Rear Tire Size:
        
        
            Typically 140/70-13 or similar. Manual will specify exact size and pressure.
        
     
    
    
        
            Wheel Type:
        
        
            Cast aluminum alloy wheels.
        
     
    
    
        
            Front Brake Type:
        
        
            Hydraulic disc brake, likely single or dual piston caliper.
        
     
    
        
            Rear Brake Type:
        
        
            Hydraulic disc brake, likely single piston caliper.
        
     
 
    
    
    
        
            Active Features:
        
        
            ABS not commonly found on this specific generation/displacement, but advanced braking systems might be present on later models. Manual will detail any available ABS or linked braking systems.
        
     
    
        
            Passive Features:
        
        
            Durable frame construction, integrated lighting, emergency stop switch, comfortable seating position for rider control.
        
     
 
    
    
    
        
            Dashboard Instruments:
        
        
            Analog speedometer, tachometer (on some versions), fuel gauge, coolant temperature gauge, indicator lights for turn signals, high beam, oil pressure, and engine check.
        
     
    
    
        
            ABS Availability:
        
        
            ABS was not standard on earlier YP125/YP150 models. The manual will clarify if any variants offer it.
        
     
    
    
        
            Headlight Type:
        
        
            Halogen bulbs, likely dual headlights for enhanced visibility. Manual specifies bulb types and replacement.
        
     
 
    
    
    
        
            Oil Change Interval:
        
        
            Typically every 3,000-5,000 km or annually. Manual will specify Yamaha's recommended intervals.
        
     
    
        
            Air Filter Replacement:
        
        
            Recommended inspection every 5,000 km, replacement every 10,000-15,000 km or as needed. Manual will provide detailed schedule.
        
     
    
        
            Spark Plug Replacement:
        
        
            Typically every 8,000-10,000 km. Manual will specify the correct spark plug type and replacement interval.
        
     
    
        
            V Belt Inspection Replacement:
        
        
            Inspection recommended every 10,000 km, replacement typically around 20,000-30,000 km. Manual will detail inspection criteria and replacement interval.
        
     
    
        
            Coolant Level Check:
        
        
            Recommended to check coolant level in the reservoir at every pre-ride inspection. Manual will specify procedure.
        
     
    
    
        
            Brake Fluid Type:
        
        
            DOT 3 or DOT 4. Manual will specify the exact required standard and replacement interval (usually every 2 years).
        
     
    
        
            Coolant Replacement Interval:
        
        
            Initial replacement at first major service (e.g., 20,000 km) and then every 2-3 years or specified mileage. Manual will provide the exact schedule.
        
     
    
        
            Gear Oil Capacity:
        
        
            Approx. 0.1 - 0.2 Liters. Manual will confirm exact capacity for the final drive gearbox.
        
     
    
    
        
            Common Wear Items:
        
        
            Wear on brake pads, tires, V-belt, and potential carburetor clogging due to fuel quality are common. Manual provides procedures for checking and replacing these.
        
     
    
        
            Electrical Reliability:
        
        
            While generally reliable, older models might experience issues with voltage regulators or starter motors. The troubleshooting section will be invaluable for diagnosing these.
        
     
    
    
        
            Engine Mount Torque:
        
        
            Specific torque values for engine mounting bolts will be provided in the manual for proper assembly.
        
     
    
        
            Wheel Hub Torque:
        
        
            Torque specifications for wheel nuts/bolts will be critical for safety and will be detailed in the manual.
        
     
 
    
    
    
        
            Brand Heritage:
        
        
            Yamaha Motor Company is a Japanese multinational corporation renowned for its wide range of products, including motorcycles, scooters, marine products, and musical instruments. In the scooter segment, Yamaha has a strong reputation for innovation, quality, and performance.
        
     
    
    
        
            Model Lineage:
        
        
            The Majesty nameplate has been used by Yamaha for decades, evolving from smaller displacement scooters to the more substantial maxi-scooter class. The Skyliner variant emphasizes comfort and touring capability for its class.
        
     
    
    
        
            Production Period:
        
        
            The YP125/YP150 Skyliner models likely saw production runs from the late 1990s through the 2000s, with potential updates. This manual would cover a specific iteration within that period.