2000 Hyosung Aquila 250 Service & Repair Manual (P/N 99000-95310)

This Hyosung Motors & Machinery Inc. service manual covers maintenance, diagnosis and repair of the 2000 Aquila 250, including its air/oil-cooled DOHC V-twin. Manual No. 99000-95310 is supplied in the second edition, dated May 2001.

• Engine repair: Engine removal and reinstallation, cylinder-head and piston service, crankcase separation, and camshaft timing procedures.

• Clutch and transmission: Clutch inspection, primary driven gear removal, gearshift-shaft service, and internal transmission inspection and assembly.

• Fuel system: Carburetor disassembly, jet and diaphragm inspection, float-height adjustment, and fuel pump and fuel cock checks.

• Electrical diagnosis: Ignition and charging tests, starter-motor overhaul, side-stand interlock circuits, and wiring diagrams.

• Brakes and chassis: Hydraulic brake bleeding, caliper and master-cylinder service, rear drum brake repair, telescopic fork overhaul, and steering-stem service.

• Workshop references: Periodic maintenance charts, exploded component drawings, engine and chassis torque tables, wear limits, and fluid specifications.

This manual is intended for readers who already have the knowledge and skills to service Hyosung vehicles; it assumes familiarity with general workshop practices.

Valve Train, Engine Internals and Lubrication

Periodic maintenance procedures cover the valve train, carburetor, clutch and drive chain. General-information pages provide identification and exterior illustrations alongside fuel, oil and brake-fluid recommendations.

Valve timing diagrams and front/rear camshaft installation illustrations support cylinder-head, valve-guide and valve-seat work. Separate intake and exhaust tappet shim selection charts relate measured clearance to installed shim thickness, helping select a replacement shim during valve service.

Internal engine coverage includes magneto rotor removal, crankshaft installation and oil pump inspection. Transmission drawings identify gear, washer and circlip positions, while inspection procedures cover clutch plates and shift-fork wear.

The primary drive gear section warns that its left-hand-threaded fastener can be damaged if turned the wrong way. The oil-filter installation diagram also identifies an orientation error that can damage the engine.

Carburetor and Fuel Delivery Checks

The Mikuni BDS 26 double-carburetor section provides separate front and rear jet specifications, needle-valve inspection and float-height adjustment. Fuel pump flow checks are supported by pump and relay resistance tests in the electrical section.

Troubleshooting tables distinguish starting, idle, high-speed running and overflow complaints, linking symptoms to the relevant jets, passages, float and fuel-supply components.

Ignition, Charging and Starting Circuits

DC-CDI ignition checks, generator output tests and regulator/rectifier resistance tables address spark and charging faults. Starter-motor inspection covers the brushes, commutator and armature.

Starter and side-stand interlock diagrams explain how the clutch, neutral and stand switches affect starting. These circuit references help distinguish an interlock problem from a starter-motor fault. Wire and cable routing drawings show harness placement around the frame and electrical components.

Forks, Steering and Brake Service

Front fork procedures cover damper-rod removal, slide-metal and seal replacement, and oil-level setting. Steering-bearing service, wheel-bearing replacement and swingarm needle-bearing work are also documented.

Rear shock absorber coverage is limited to removal, inspection, replacement and spring-preload adjustment. The manual identifies these shocks as non-serviceable and warns against disassembly.

Brake sections cover front caliper and master-cylinder inspection, rear drum and shoe checks, and hydraulic circuit bleeding. Follow the manual's brake-fluid handling and bleeding precautions; trapped air reduces braking performance.

A Preview of Engine Test and Clearance Data

These examples are a small selection of the engine inspection specifications in the manual. Cold valve clearance is 0.1–0.2 mm for the intake valves and 0.2–0.3 mm for the exhaust valves.

The compression-test standard is 14–16 kg/cm² at 600 rpm, with the engine warmed up and the throttle fully open; the service limit is 12 kg/cm² at the same speed.

Piston-to-cylinder clearance is specified at 0.05–0.06 mm, with a 0.120 mm service limit for assessing wear during internal engine inspection.

PDF Search, Page Bookmarks and Diagram Detail

Search and navigation: PDF text search is unavailable. Embedded bookmarks link to individual pages using numbered filenames. Some small wire-color codes in the full wiring diagram remain difficult to read when enlarged.

Download one printable, English-language, 205-page PDF. The total comprises 196 chapter pages, two tappet shim charts, one cover page, three introductory pages, two blank pages and one publication-information page.