1995-1999 Yamaha YP250, Majesty 250 Maxi Scooter - Factory Diagnostics & Repair Guide

Yamaha YP250 Service Manual - 1996 Edition

This official service documentation provides the essential technical foundation for the maintenance and repair of the 249cc liquid-cooled engine and chassis systems. High-precision service is supported by the requirement for Yamaha bond No. 1215 on all crankcase mating surfaces to ensure airtight structural integrity and prevent terminal oil pressure loss during high-temperature operation. Consistent application of these factory-specified sealants is vital for long-term engine uptime and the prevention of catastrophic lubrication failure.

Technical Applicability & Serial Ranges

Yamaha YP250 Series (First Generation)

• Technical Code 4UC 1: Standard international configuration (Excluding CH, A markets).
• Technical Code 4UD1: Specific regional configuration (For CH, A markets).
• Handelsname: Yamaha Majesty 250 (1996).

Frame & Engine Identification

• Frame Serial Number: Stamped into the right side of the chassis frame.
• Engine Serial Number: Stamped directly into the crankcase casting.
• Model Label: Located under the seat assembly for precise spare parts procurement.

Operational Efficiency & Safety Proof Points

• System Reliability: Step-by-step diagnostic procedures for the Auto-Choke and Ignition Circuit Cut-off systems prevent intermittent starting issues and enhance operator safety.
• Service Accuracy: Integrated exploded diagrams with numbered job sequences facilitate rapid component identification and reduce assembly errors during complex overhauls.
• Maintenance Optimization: The pulse-counted oil indicator light system automates service scheduling, triggering alerts at the initial 1,000 km and subsequent 3,000 km intervals to protect internal engine components.

Document Metadata

• Print No: EB000000
• Page Count: 422 Pages

Technical Depth & Factory Benchmarks

The YP250 utilizes a forward-inclined single-cylinder SOHC architecture with a 69.0 x 66.8 mm bore and stroke. Engine health is verified through a standard compression pressure of 1,400 kPa (14 bar) at 500 r/min. Critical clearances include a cylinder warpage limit of 0.03 mm and a piston-to-cylinder clearance specification of 0.02 to 0.04 mm. The electrical system is governed by a digital T.C.I. ignition with a pickup coil resistance range of 168 to 252 Ω at 20°C.

Visual Navigation Aids

Technical procedures are supported by the following schematic and illustrative categories:

• System Architecture: Detailed circuit diagrams for the ignition, charging, and signaling systems.
• Exploded Views: Comprehensive parts breakdowns for the cylinder head, V-belt transmission, and secondary sheave assemblies.
• Cable Routing: Precise mapping of wireharness, vacuum hose, and brake cable paths to prevent mechanical interference.
• Symbolic Legend: Standardized iconography for lubrication points, tightening requirements, and mandatory replacement parts.

Table of Contents

• Chapter 1: General Information: Identification, features, and special tool requirements.
• Chapter 2: Specifications: Maintenance data, torque values, and lubrication grades.
• Chapter 3: Periodic Inspection and Adjustment: Service intervals, engine tuning, and chassis alignment.
• Chapter 4: Engine Overhaul: Detailed disassembly and assembly of all internal power unit components.
• Chapter 5: Cooling System: Radiator, water pump, and thermostat service.
• Chapter 6: Carburetion: Carburetor disassembly, fuel pump inspection, and auto-choke diagnostics.
• Chapter 7: Chassis: Front/rear wheel, brake system, and steering overhaul.
• Chapter 8: Electrical: Circuit testing, switch diagnostics, and lighting system repair.
• Chapter 9: Troubleshooting: Systematic fault isolation for engine and electrical failure.

Operational Limits & Specifications

• Torque Sequences:
  • Cylinder Head Nut (M8): 22 Nm (2.2 m·kg)
  • Rotor Nut (M16): 80 Nm (8.0 m·kg)
  • Clutch Carrier Nut (M36): 90 Nm (9.0 m·kg)
  • Front Wheel Axle Nut (M14): 70 Nm (7.0 m·kg)
• Fluid Capacities & Types:
  • Engine Oil: 1.2 L (Periodic change) / 1.4 L (Total amount); Type: SAE 10W-30 or 20W-40 (API SE or higher).
  • Transmission Oil: 0.25 L.
  • Cooling System: 1.4 L (Ethylene glycol antifreeze).
  • Brake Fluid: DOT #4.
• Mechanical Clearances:
  • Intake Valve (Cold): 0.08 - 0.12 mm.
  • Exhaust Valve (Cold): 0.16 - 0.20 mm.
  • Spark Plug Gap (NGK DR8EA): 0.6 - 0.7 mm.