2003 Hyosung Comet 650 Service Manual PDF (P/N 99000-94810)

This Hyosung service manual covers the 2003 Comet 650 with its carbureted V-twin engine and chassis systems. It is Manual No. 99000-94810, first edition, September 2003.

Text search, bookmarks and wiring detail: Searchable text runs through the service chapters, with embedded bookmarks for all eight sections and many individual topics. Some lettering within illustrations is not searchable. Small wire-color labels in the main wiring diagram are readable when enlarged.

• Engine repair: Engine removal, crankcase separation, cylinder-head overhaul, piston and crankshaft inspection, camshaft installation, and valve-timing procedures.

• Clutch and transmission: Wet-clutch inspection, shaft and gear reassembly, shift-fork measurements, and gearshift mechanism checks.

• Carbureted fuel system: BDSR39 twin-carburetor disassembly, jet and needle inspection, float-height adjustment, and fuel-cock and fuel-pump checks.

• Cooling system: Radiator and water-pump service, thermostat and temperature-sensor testing, fan diagnosis, coolant replacement, flushing, and circuit bleeding.

• Brakes and chassis: Brake bleeding, caliper overhaul, front master-cylinder repair, telescopic fork servicing, steering bearings, wheels, and swingarm inspection.

• Electrical diagnosis: Ignition and charging tests, starter-motor repair, side-stand interlock diagrams, switch checks, and the full wiring diagram.

The manual is intended for readers already skilled in servicing Hyosung motorcycles and assumes general mechanical knowledge.

Engine Overhaul, Valve Timing and Transmission

Internal engine inspection covers cylinder-head distortion, camshaft wear and journal clearance, piston and ring wear, connecting rods, and crankshaft runout and alignment. Compression and oil-pressure tests provide reference data for assessing engine condition.

Front- and rear-cylinder camshaft installation is shown separately. The Valve Timing Diagram and intake/exhaust Tappet Shim Selection Charts support valve-clearance work, while transmission assembly views identify gear, washer, spacer and circlip positions.

Clutch service distinguishes the No. 1 and No. 2 drive plates and covers driven-plate distortion, spring condition and the release bearing.

The manual warns that separating the crankcase from the wrong side can damage the gearshift cam stopper. It also identifies the primary-drive gear nut's left-hand thread and the damage risk from turning it the wrong way.

BDSR39 Carburetors and Fuel Delivery

Exploded carburetor views accompany diaphragm, jet, needle-valve and float inspection. Front and rear carburetor specifications are tabulated separately. The CO adjustment screw carries a specific warning against disturbing the balance between the two carburetors.

Fuel-pump checks address fuel delivery, the fuel cock and connected hoses. The Fuel Hose Routing view distinguishes the carburetor supply, tank supply and vacuum connections.

Cooling-System Tests and Water-Pump Service

Bench tests cover the thermostat, cooling-fan thermo-switch and coolant-temperature sensor, with their corresponding test specifications. The Cooling Circuit drawing traces flow through both cylinders.

Water-pump repair covers impeller and bearing service, with checks for oil-seal and O-ring leakage. Coolant recommendations, radiator cleaning and cooling-circuit air bleeding are documented alongside the component procedures.

Brakes, Forks and Steering Bearings

Brake coverage extends to caliper pistons and seals, disc inspection, and front master-cylinder disassembly and reassembly.

Fork service includes seals, springs, oil-level setting, and rebound and compression damping adjustments. Suspension scope: The fork cap and damper cartridge are not to be dismantled; the rear shock absorber is treated as a replacement assembly.

Steering-stem bearing and race service, wheel-bearing replacement, and swingarm pivot-bearing work are also covered.

Ignition, Charging and No-Start Diagnosis

Electrical repair procedures include igniter, pickup-coil, regulator/rectifier and pulse-control-unit tests, plus starter brush, commutator and armature inspection.

The Starter System and Side Stand Ignition Interlock System diagrams and switch-state table help distinguish an interlock-related no-start from a starter fault. Wire and cable routing views identify harness paths and front/rear ignition-coil connections.

Troubleshooting tables group starting, shifting, overheating, charging, suspension and brake complaints by symptom, possible cause and remedy. Fuel and electrical work require the manual's precautions for flammable fuel and battery isolation.

Maintenance Specifications and Special Tools

Periodic maintenance covers lubrication, break-in guidance, oil/filter service, exhaust fastener tightening, clutch-cable adjustment and drive-chain tensioning. Fluid recommendations include SAE 10W/40 engine oil and DOT 4 brake fluid.

Torque tables cover engine mounts, cylinder heads, crankcases and oil-drain fasteners. Service data supplies fluid capacities, wear limits and electrical test values. Named workshop tools include crankcase separator 09920-13120, clutch sleeve hub holder 09920-53710 and fork oil-level gauge 09943-74111.

English PDF and Included Pages

One printable 210-page PDF contains 204 pages across the eight service sections, five front-matter pages including the original cover, and one publication page. The intake and exhaust shim charts are included in the service-section count; all introductory and publication pages are already included in the total.