Complete factory service repair manual for the 2002-2010 Hyosung Comet GT250 with its distinctive liquid-cooled V-twin engine. Covers dual carburetor synchronization, engine rebuild, valve adjustment, suspension overhaul, brake service, electrical troubleshooting, and all maintenance tasks for this popular 250cc sport motorcycle.
2002-2010 Hyosung GT250 Service Repair Workshop Manual PDF
VEHICLE/EQUIPMENT INTRODUCTION:
The Hyosung GT250 Comet, produced from 2002 through 2010, was the mid-displacement sibling in Hyosung's Comet sport bike lineup, sitting between the entry-level GT125 and the larger GT650. The GT250 was powered by a liquid-cooled 249cc V-twin engine, making it one of the few genuine V-twin motorcycles in the 250cc class -- a segment otherwise dominated by parallel twins and single-cylinder engines. This V-twin configuration gave the GT250 a distinctive broad powerband, smoother delivery, and a satisfying exhaust note that appealed to riders looking for a step up from entry-level bikes. The steel perimeter frame, clip-on handlebars, rear-set footpegs, and full sport fairing gave it the aggressive stance of a larger supersport. Hyosung, based in South Korea, designed the GT250 with input from engineers familiar with Japanese sport bike engineering, resulting in a machine that offered compelling specifications at a highly competitive price point. The GT250 found markets across Europe, Asia, Australia, and North America, particularly among riders who wanted sport bike styling with manageable power and low insurance costs.
SERVICE AND REPAIR SCOPE:
- Hyosung GT250 2002-2010 General Information
- Hyosung GT250 Fuel system - dual carburetor synchronization, jet replacement
- Hyosung GT250 Cooling system - coolant drain and refill, radiator inspection
- Hyosung GT250 Engine top end - V-twin cylinder heads, cam chain tensioner
- Hyosung GT250 Clutch - cable adjustment, plate thickness measurement
- Hyosung GT250 Engine lubrication - oil filter, strainer screen cleaning
- Hyosung GT250 Engine removal and installation procedures
- Hyosung GT250 Crankshaft - bearing inspection, end float measurement
- Hyosung GT250 Transmission - gear shift drum, shift fork inspection
- Hyosung GT250 Wheels and tires - spoke lacing, rim tape replacement
- Hyosung GT250 Final drive - chain adjustment, sprocket wear limits
- Hyosung GT250 Brakes - caliper piston retraction, pad wear limits
- Hyosung GT250 Suspension - fork cartridge service, shock preload
- Hyosung GT250 Steering - steering head bearing preload, dust seal
- Hyosung GT250 Frame and fairing fastener locations
- Hyosung GT250 Electrical system - regulator output, stator resistance
- V-twin dual carburetor vacuum synchronization procedure
- Valve clearance adjustment with shim-over-bucket method
- Spark plug gap and heat range specifications per operating climate
- Ignition coil primary and secondary resistance testing
- Coolant thermostat opening temperature verification
TECHNICAL SPECIFICATIONS:
- Manufacturer: Hyosung Motors
- Model: Comet GT250
- Years: 2002-2010
- Engine: Liquid-cooled, 4-stroke, DOHC, 75-degree V-twin
- Displacement: 249cc
- Bore x stroke: approximately 61.0 mm x 42.5 mm
- Compression ratio: approximately 11.5:1
- Maximum power: approximately 30 hp at 10,500 rpm
- Transmission: 6-speed constant mesh
- Clutch: Wet multi-plate, cable operated
- Frame: Steel perimeter/twin-spar
- Front suspension: 41mm telescopic fork
- Rear suspension: Swingarm with adjustable monoshock
- Front brake: Single 300mm disc with dual-piston caliper
- Rear brake: Single disc or drum depending on year
- Fuel capacity: approximately 17 liters
- Seat height: approximately 790 mm
DIAGNOSTIC INFORMATION:
- Uneven power delivery between cylinders: synchronize dual carburetors using vacuum gauges, inspect carburetor slide diaphragm for tears, check idle jet clogging
- V-twin overheating in traffic: verify cooling fan activation, bleed coolant system to remove air pockets, inspect radiator cap pressure rating
- Clutch slipping at higher rpm: check friction plate stack height against minimum, inspect clutch spring loaded length, adjust cable free play
- Hard cold starts: inspect choke enrichener plunger return, verify spark plug firing, check fuel float level in each carburetor bowl
- Fork seal weeping oil: clean fork stanchion of road grime, inspect dust wiper for damage, replace fork seals and set correct oil height
- Rear shock leaking or bottoming: inspect shock shaft for pitting, increase preload setting, consider shock rebuild with new nitrogen charge
- Electrical charging below specification: measure regulator rectifier DC output at battery at 5000 rpm, check stator three-phase AC resistance, inspect wiring connector for heat damage
ILLUSTRATIONS AND DIAGRAMS INCLUDED:
- V-twin engine exploded view with timing chain and camshaft detail
- Dual carburetor assembly with vacuum port locations marked
- Complete wiring harness schematic with connector pin assignments
- Front fork cartridge exploded assembly with damper rod
- Swingarm pivot and rear shock mounting detail
- Brake caliper piston and dust seal arrangement
- Frame and fairing panel mounting locations with fastener sizes
- Transmission gear set and shift drum selector fork positions
COMPATIBILITY:
- Hyosung Comet GT250 model years 2002-2010
- File format: Searchable PDF
FILE PROPERTIES:
- Format: Searchable PDF
- Language: English
- Delivery: Instant digital download
- Access: Download anytime after purchase
2002-2010 Hyosung GT250 Service Repair Workshop Manual PDF
VEHICLE/EQUIPMENT INTRODUCTION:
The Hyosung GT250 Comet, produced from 2002 through 2010, was the mid-displacement sibling in Hyosung's Comet sport bike lineup, sitting between the entry-level GT125 and the larger GT650. The GT250 was powered by a liquid-cooled 249cc V-twin engine, making it one of the few genuine V-twin motorcycles in the 250cc class -- a segment otherwise dominated by parallel twins and single-cylinder engines. This V-twin configuration gave the GT250 a distinctive broad powerband, smoother delivery, and a satisfying exhaust note that appealed to riders looking for a step up from entry-level bikes. The steel perimeter frame, clip-on handlebars, rear-set footpegs, and full sport fairing gave it the aggressive stance of a larger supersport. Hyosung, based in South Korea, designed the GT250 with input from engineers familiar with Japanese sport bike engineering, resulting in a machine that offered compelling specifications at a highly competitive price point. The GT250 found markets across Europe, Asia, Australia, and North America, particularly among riders who wanted sport bike styling with manageable power and low insurance costs.
SERVICE AND REPAIR SCOPE:
- Hyosung GT250 2002-2010 General Information
- Hyosung GT250 Fuel system - dual carburetor synchronization, jet replacement
- Hyosung GT250 Cooling system - coolant drain and refill, radiator inspection
- Hyosung GT250 Engine top end - V-twin cylinder heads, cam chain tensioner
- Hyosung GT250 Clutch - cable adjustment, plate thickness measurement
- Hyosung GT250 Engine lubrication - oil filter, strainer screen cleaning
- Hyosung GT250 Engine removal and installation procedures
- Hyosung GT250 Crankshaft - bearing inspection, end float measurement
- Hyosung GT250 Transmission - gear shift drum, shift fork inspection
- Hyosung GT250 Wheels and tires - spoke lacing, rim tape replacement
- Hyosung GT250 Final drive - chain adjustment, sprocket wear limits
- Hyosung GT250 Brakes - caliper piston retraction, pad wear limits
- Hyosung GT250 Suspension - fork cartridge service, shock preload
- Hyosung GT250 Steering - steering head bearing preload, dust seal
- Hyosung GT250 Frame and fairing fastener locations
- Hyosung GT250 Electrical system - regulator output, stator resistance
- V-twin dual carburetor vacuum synchronization procedure
- Valve clearance adjustment with shim-over-bucket method
- Spark plug gap and heat range specifications per operating climate
- Ignition coil primary and secondary resistance testing
- Coolant thermostat opening temperature verification
TECHNICAL SPECIFICATIONS:
- Manufacturer: Hyosung Motors
- Model: Comet GT250
- Years: 2002-2010
- Engine: Liquid-cooled, 4-stroke, DOHC, 75-degree V-twin
- Displacement: 249cc
- Bore x stroke: approximately 61.0 mm x 42.5 mm
- Compression ratio: approximately 11.5:1
- Maximum power: approximately 30 hp at 10,500 rpm
- Transmission: 6-speed constant mesh
- Clutch: Wet multi-plate, cable operated
- Frame: Steel perimeter/twin-spar
- Front suspension: 41mm telescopic fork
- Rear suspension: Swingarm with adjustable monoshock
- Front brake: Single 300mm disc with dual-piston caliper
- Rear brake: Single disc or drum depending on year
- Fuel capacity: approximately 17 liters
- Seat height: approximately 790 mm
DIAGNOSTIC INFORMATION:
- Uneven power delivery between cylinders: synchronize dual carburetors using vacuum gauges, inspect carburetor slide diaphragm for tears, check idle jet clogging
- V-twin overheating in traffic: verify cooling fan activation, bleed coolant system to remove air pockets, inspect radiator cap pressure rating
- Clutch slipping at higher rpm: check friction plate stack height against minimum, inspect clutch spring loaded length, adjust cable free play
- Hard cold starts: inspect choke enrichener plunger return, verify spark plug firing, check fuel float level in each carburetor bowl
- Fork seal weeping oil: clean fork stanchion of road grime, inspect dust wiper for damage, replace fork seals and set correct oil height
- Rear shock leaking or bottoming: inspect shock shaft for pitting, increase preload setting, consider shock rebuild with new nitrogen charge
- Electrical charging below specification: measure regulator rectifier DC output at battery at 5000 rpm, check stator three-phase AC resistance, inspect wiring connector for heat damage
ILLUSTRATIONS AND DIAGRAMS INCLUDED:
- V-twin engine exploded view with timing chain and camshaft detail
- Dual carburetor assembly with vacuum port locations marked
- Complete wiring harness schematic with connector pin assignments
- Front fork cartridge exploded assembly with damper rod
- Swingarm pivot and rear shock mounting detail
- Brake caliper piston and dust seal arrangement
- Frame and fairing panel mounting locations with fastener sizes
- Transmission gear set and shift drum selector fork positions
COMPATIBILITY:
- Hyosung Comet GT250 model years 2002-2010
- File format: Searchable PDF
FILE PROPERTIES:
- Format: Searchable PDF
- Language: English
- Delivery: Instant digital download
- Access: Download anytime after purchase
