Target Audience:
Owners and independent repair shops specializing in Hyosung motorcycles.
Value Proposition:
Provides factory-level repair information, enabling owners to perform maintenance and repairs themselves, saving on dealership costs and ensuring proper vehicle care.
Competitive Advantage:
Offers a definitive source of truth for Hyosung Comet GT models, crucial for maintaining vehicle integrity and resale value, especially given the brand's niche market position in some regions.
Visual Aids:
Hundreds of photos and detailed diagrams illustrating disassembly and reassembly procedures.
Technical Diagrams:
Includes comprehensive wiring diagrams for accurate electrical troubleshooting.
Covered Models:
Hyosung Comet GT125, Hyosung Comet GT250
Engine Variants Covered:
125cc and 250cc engine configurations
Manual Scope:
Comprehensive maintenance, repair, and operational information
Estimated Page Count:
Estimated 300-500 pages (based on typical factory service manuals of this scope)
Manual Type:
Factory Service Manual & Owner's Manual
Engine Systems:
Engine disassembly, assembly, diagnostics, tuning, cooling system, lubrication system, ignition system, fuel system (carburetor/injection depending on year/model), exhaust system, emissions control.
Transmission Drivetrain:
Clutch operation and adjustment, gearbox disassembly and reassembly, chain drive maintenance and adjustment, final drive.
Chassis Suspension:
Front fork overhaul and adjustment, rear shock absorber inspection and replacement, swingarm maintenance, wheel bearing service, steering system.
Braking System:
Front and rear brake caliper service, master cylinder overhaul, brake pad replacement, brake fluid bleeding and replacement, hydraulic system diagnostics.
Electrical System:
Battery service, charging system (alternator/stator, rectifier/regulator), starting system (starter motor, starter clutch), lighting system (headlight, taillight, turn signals), instrumentation, horn, wiring diagrams for all circuits.
Fuel System:
Fuel tank maintenance, fuel lines, carburetor disassembly/cleaning/adjustment (for GT125/early GT250) or fuel injection system diagnostics (for later GT250 models), fuel pump operation.
Bodywork Cosmetics:
Fairing removal and installation, seat maintenance, fuel tank removal, fenders, and other body panels.
Maintenance Procedures:
Scheduled maintenance (oil changes, filter replacements, chain lubrication), pre-ride inspections, seasonal storage procedures.
Repair Procedures:
Step-by-step instructions for component removal, disassembly, cleaning, inspection, repair, and reassembly.
Troubleshooting Diagnostics:
Fault finding guides, symptom-based troubleshooting, diagnostic procedures for electrical and mechanical issues.
Technical Specifications Data:
Torque specifications for all fasteners, fluid capacities, clearances, tolerances, electrical resistance values, diagnostic data.
Wiring Diagrams:
Detailed, high-quality wiring schematics for all electrical systems, color-coded for clarity.
Depth Of Coverage:
Comprehensive; suitable for both novice DIY mechanics and professional technicians. Covers everything from basic owner maintenance to complete engine rebuilds and electrical system diagnostics.
Engine Type Gt125:
Typically a V-twin, air-cooled, 4-stroke
Displacement Gt125:
125cc
Engine Type Gt250:
Typically a V-twin, air-cooled, 4-stroke (later models may feature oil-cooling or minor variations)
Displacement Gt250:
249cc
Bore X Stroke Gt125:
Varies by specific model year, typically around 44mm x 41mm
Bore X Stroke Gt250:
Varies by specific model year, typically around 57mm x 48.8mm
Compression Ratio Gt125:
Typically around 10.0:1
Compression Ratio Gt250:
Typically around 10.0:1
Horsepower Gt125:
Approx. 13-15 HP (dependent on market regulations and exact model year)
Horsepower Gt250:
Approx. 25-28 HP (dependent on market regulations and exact model year)
Fuel Delivery Gt125:
Carburetor (typically dual Mikuni VM-series or similar)
Fuel Delivery Gt250:
Carburetor (dual) or Fuel Injection (on later/specific models).
Fuel Type:
Unleaded gasoline
Length Gt125:
Approx. 2170 mm (85.4 in)
Width Gt125:
Approx. 750 mm (29.5 in)
Height Gt125:
Approx. 1140 mm (44.9 in)
Wheelbase Gt125:
Approx. 1445 mm (56.9 in)
Length Gt250:
Approx. 2170 mm (85.4 in)
Width Gt250:
Approx. 750 mm (29.5 in)
Height Gt250:
Approx. 1140 mm (44.9 in)
Wheelbase Gt250:
Approx. 1445 mm (56.9 in)
Dry Weight Gt125:
Approx. 163 kg (360 lbs)
Dry Weight Gt250:
Approx. 170 kg (375 lbs)
Fuel Tank Capacity:
Approx. 14 Liters (3.7 US gal)
Braking System Type:
Hydraulic disc brakes, front and rear.
Front Brake Rotor Diameter:
Typically 290mm for GT250, 270mm for GT125.
Rear Brake Rotor Diameter:
Typically 230mm.
Lighting:
Halogen headlight, LED taillight and turn signals (depending on model year/spec).
Engine Oil Change:
Recommended every 3,000 km (1,864 miles) or 6 months, whichever comes first. (Refer to manual for exact intervals).
Oil Filter Replacement:
Recommended at every oil change or as specified in the manual.
Spark Plug Replacement:
Typically recommended every 6,000-10,000 km (3,700-6,200 miles).
Valve Clearance Check:
Recommended at initial 1,000 km and then every 6,000 km (3,700 miles).
Engine Oil Type:
SAE 10W-40 API SG or higher motorcycle specific oil. (Verify with manual for specific viscosity and API rating).
Engine Oil Capacity Gt125:
Approx. 1.6 L (1.7 US qt) without filter, 1.8 L (1.9 US qt) with filter.
Engine Oil Capacity Gt250:
Approx. 1.6 L (1.7 US qt) without filter, 1.8 L (1.9 US qt) with filter.
Coolant Type:
If liquid-cooled variants exist, typically a 50/50 mixture of ethylene glycol-based coolant and distilled water.
Common Wear Items:
Chain and sprockets, brake pads, tires, clutch plates (due to frequent use).
Electrical Gremlins:
Potential for minor electrical issues, especially with aging wiring or connections. The manual's wiring diagrams are essential here.
Carburetor Tuning:
Carburetors may require periodic cleaning and tuning, particularly after long periods of storage or if fuel quality is inconsistent.
Manufacturer:
Hyosung Motors & Manufacturing Co., Ltd. (South Korea)
Comet Series Introduction:
The Comet series, known for its cruiser-inspired styling, has been a staple for Hyosung, offering accessible displacement options.
Gt125 Gt250 Relationship:
The GT125 and GT250 share a common platform and design philosophy, differing primarily in engine displacement and associated performance characteristics.
Production Period:
Production spans various years, with the GT125 and GT250 being popular models globally, particularly in the entry-level and middleweight segments.
