1987 Honda TRX250X Parts Manual

The 1987 Honda TRX250X is a four-stroke, single-cylinder sport ATV featuring a 246cc OHC engine, five-speed transmission with reverse, shaft drive, front and rear suspension, front disc brake, rear drum brake, electric start, and full instrumentation. This parts manual provides comprehensive information for identification, ordering, and replacement of all components. Below are key sections covering parts identification, exploded diagrams, part numbers, ordering information, and maintenance specifications.

1. General Information 2. Engine Components 3. Transmission & Drive System 4. Chassis & Frame 5. Suspension System 6. Braking System 7. Electrical System 8. Fuel System 9. Controls & Instruments 10. Body & Accessories 11. Parts Ordering & Reference

General Information

Model identification: TRX250X, VIN location: right side of frame near steering head. Engine serial number: left side of crankcase.

Specification	Description
Model Year	1987
Engine Type	246cc 4-stroke OHC single cylinder
Bore x Stroke	74.0mm x 57.8mm
Compression Ratio	9.6:1
Transmission	5-speed with reverse
Drive System	Shaft drive
Starting System	Electric start with backup kick starter
Fuel Capacity	2.6 gallons (9.8 liters)
Dry Weight	324 lbs (147 kg)
Ground Clearance	6.7 inches (170mm)

Engine Components

Complete engine assembly and sub-components.

Cylinder Head Assembly: Includes valves, springs, camshaft, rocker arms.
Cylinder & Piston: Cylinder, piston, rings, wrist pin.
Crankcase & Crankshaft: Lower engine case, crankshaft, connecting rod.
Clutch Assembly: Clutch plates, springs, basket, cable.
Ignition System: CDI unit, spark plug, ignition coil, pulse generator.

WARNING! Engine components under high stress; use genuine Honda parts only for replacement.

Transmission & Drive System

Five-speed transmission with reverse gear and shaft drive components.

Transmission Gears: Main shaft, countershaft, gear sets.
Shift Mechanism: Shift drum, forks, shift lever assembly.
Drive Shaft: Front and rear drive shafts, universal joints.
Final Drive: Rear differential assembly, gear oil specifications.
Reverse System: Reverse gear mechanism, engagement lever.

CAUTION! Use recommended gear oil; improper lubrication can cause transmission failure.

Chassis & Frame

Frame Type: Steel tubular frame with integrated engine mounts.
Frame Parts: Main frame, subframe, brackets, mounting points.
Wheel Hubs: Front and rear hub assemblies, bearings, seals.
Axles: Front and rear axles, axle nuts, lock washers.
Footpegs: Rider and passenger footpegs, mounting hardware.
Skid Plates: Engine and frame protection plates.
Tow Hooks: Front and rear tow points.

Suspension System

Front: Independent double wishbone with shocks. Rear: Swingarm with single shock.

Front Suspension: Upper/lower A-arms, ball joints, tie rods, shock absorbers.

Rear Suspension: Swingarm assembly, pivot bearings, rear shock, linkage system. Steering: Steering stem, bearings, handlebar clamp. Wheels & Tires: Front 22x7-10, Rear 22x10-9, wheel rims, valve stems.

Braking System

Front: Hydraulic disc brake. Rear: Mechanical drum brake.

Front Brake: Master cylinder, caliper, brake pads, rotor, brake lines.
Rear Brake: Brake pedal, cable, drum assembly, brake shoes, springs.
Parking Brake: Lever mechanism, cable routing.

Tip: Regular brake inspection recommended; replace worn components immediately.

Electrical System

12V electrical system with battery, alternator, and complete wiring harness.

Charging System: Alternator, regulator/rectifier, stator assembly.
Starting System: Starter motor, solenoid, battery, cables.
Lighting: Headlight, taillight, brake light, indicator lights.
Ignition System: CDI unit, spark plug, ignition coil, kill switch.
Instruments: Speedometer, indicator lights, wiring connectors.
Switches: Handlebar controls, key switch, brake light switches.

WARNING! Disconnect battery before electrical work to prevent shorts.

Fuel System

Carburetor type: 26mm constant velocity. Fuel tank capacity: 2.6 gallons.

Fuel Tank: Tank assembly, cap, mounting straps, petcock.
Carburetor: Main body, jets, float, needle valve, throttle cable.
Air Intake: Air filter box, filter element, intake tube.
Exhaust System: Header pipe, muffler, mounting brackets.
Fuel Lines: Supply and return lines, clamps, fittings.

Controls & Instruments

Handlebar controls and instrument panel components.

Body & Accessories

Plastic body panels, seat, and accessory mounting points.

CAUTION! Use proper fasteners; improper installation can cause panel damage.

Parts Ordering & Reference

Part Category	Honda Part Number Prefix	Notes
Engine Components	12000-	Use engine serial number for exact match
Transmission	23200-	Specify gear position when ordering
Electrical	30000-	Include wire color codes if applicable
Brakes	43000-	Specify front/rear and side
Suspension	51000-	Include side (left/right) for asymmetric parts

Ordering: Contact authorized Honda dealer with part numbers and VIN.

Support: Honda Customer Service: 1-866-784-1870; www.hondaparts-direct.com