Market Position:
Targeted at KTM owners, independent repair shops, and parts suppliers specializing in off-road motorcycles of the late 1990s, particularly those seeking to maintain or restore the 250, 300, and 380 engine platforms.
Competitive Analysis:
This manual is essential for owners of these specific KTM models, offering a crucial resource that complements (or sometimes surpasses in detail for parts) official service manuals. Its strength lies in its explicit focus on engine parts and exploded views, aiding in precise identification and order accuracy.
Key Features:
Fully illustrated parts list, exploded views, comprehensive engine component breakdown, part numbering for ordering, aids disassembly and assembly.
Coverage Areas:
Engine Components, Internal Engine Parts, Disassembly and Assembly Procedures for Engine Internals.
Page Count:
Estimated 150-250 pages (typical for a comprehensive parts manual of this era).
Manual Type:
Parts Manual / Illustrated Parts List (IPL)
Format:
Printed (likely spiral-bound or stapled booklet).
Systems Covered:
Engine Internals: Cylinder, Piston, Crankshaft, Connecting Rod, Crankcase, Cylinder Head, Valves, Camshaft (if applicable to specific model variant, though most are 2-stroke), Carburetor Components, Ignition System Components (engine related), Cooling System Components (engine related).
Procedures Included:
Disassembly steps (visualized via exploded views), Assembly guidance (visualized via exploded views), Part identification and numbering for ordering.
Technical Depth:
Detailed component identification and exploded views for a thorough understanding of internal engine architecture and part relationships. Facilitates accurate part sourcing and provides visual aid for repair and reassembly.
Parts Identification Method:
Utilizes clear line drawings with numbered callouts corresponding to a detailed parts list, including OEM part numbers.
Components Detailed In Manual:
Pistons, Piston Rings, Gudgeon Pins, Circlips, Connecting Rods, Crankshafts, Crankshaft Bearings, Crankcase Halves, Crankcase Bolts, Cylinder Assemblies, Cylinder Heads, Spark Plugs, Cylinder Studs, Reed Valves, Intake Manifolds, Carburetor Mounting Flanges, Clutch Basket, Clutch Hub, Clutch Plates, Pressure Plates, Clutch Springs, Transmission Gears, Shift Forks, Shift Drum, Countershafts, Mainshafts, Output Shafts, Kickstart Mechanism components.
Cross Referencing Capability:
While not a primary function of a parts manual, the exploded views can implicitly aid in understanding how different components fit together, indirectly assisting in troubleshooting assembly errors.
File Format:
N/A (assuming printed format)
Print Quality:
High-quality paper with clear, crisp illustrations and text. Professional printing standards for clarity and durability.
Binding Type:
Likely saddle-stitched or perfect bound for ease of use and durability in a workshop environment.
Paper Type:
Durable, semi-gloss paper stock to withstand workshop conditions and ensure clarity of illustrations.
Illustration Type:
Detailed exploded view diagrams with part numbers clearly indicated.
Text Legibility:
Sharp, clear fonts ensuring easy reading of part names and numbers in various lighting conditions.
Engine Type:
2-Stroke, Single Cylinder (liquid-cooled, typically reed valve induction)
Engine Displacement 250:
Approx. 249 cc
Engine Displacement 300:
Approx. 293 cc
Engine Displacement 380:
Approx. 373 cc
Bore Stroke 250 Typical:
Approx. 66.4 mm x 72 mm
Bore Stroke 300 Typical:
Approx. 72 mm x 72 mm
Bore Stroke 380 Typical:
Approx. 82.5 mm x 72 mm
Compression Ratio Typical:
Approx. 8.0:1 to 9.0:1 (varies by specific model and tuning)
Carburetor Size Typical:
36mm - 38mm Keihin PWK or Mikuni TMX
Fuel Type:
Unleaded Gasoline (minimum 95 RON) with 2-stroke oil pre-mix (typically 40:1 or 50:1, consult specific model service manual).
Cooling System Type:
Liquid-Cooled
Ignition System Type:
Electronic Ignition (CDI)
Lubrication System:
Pre-mix lubrication via fuel.
Wheelbase Typical:
Approx. 1460 mm - 1490 mm
Ground Clearance Typical:
Approx. 350 mm - 380 mm
Dry Weight Typical:
Approx. 100 kg - 110 kg (varies by model variant EXC/SX/GS)
Fuel Tank Capacity Typical:
Approx. 7.5 liters - 12 liters (depending on variant and tank size)
Safety Ratings:
N/A (Off-road motorcycles are not typically subjected to standardized road safety ratings like NHTSA or Euro NCAP).
Active Safety Features:
Disc Brakes (Front & Rear), High-performance suspension systems for stability and control.
Passive Safety Features:
Sturdy frame construction, Handguards (often standard or easily added) for rider protection.
Top End Rebuild Interval:
Highly variable based on usage, riding style, and maintenance. Typical interval for a performance-oriented 2-stroke: 50-150 hours of hard use. This manual aids in identifying parts for such rebuilds.
Spark Plug Replacement Interval:
Every 10-20 hours of use, or as needed based on fouling.
Transmission Oil Type:
SAE 10W/40 or SAE 75W/90 motorcycle-specific gear oil (e.g., Motorex Gear Oil, Bel-Ray).
Coolant Type:
Ethylene Glycol based coolant with corrosion inhibitors for aluminum engines (e.g., Motorex Coolant M3.0).
2 Stroke Oil Type:
High-quality synthetic 2-stroke racing oil for premix applications (e.g., Motorex Cross Power 2T).
Common Wear Items:
Piston rings, piston itself, connecting rod bearings, crank seals, clutch plates, kickstarter mechanism wear.
Carburetor Tuning:
Can be sensitive to altitude and temperature; proper jetting is crucial for optimal performance and engine longevity.
Cylinder Head Gasket:
While 2-strokes don't have traditional head gaskets like 4-strokes, the seal between the cylinder and head is critical. Overtightening or improper seating can lead to leaks.
Part Number Utility:
Provides OEM part numbers essential for accurate ordering of replacement components from KTM dealerships or aftermarket suppliers.
Brand Heritage:
KTM, an Austrian manufacturer, has a strong heritage in off-road motorcycle racing and production, known for its 'Ready to Race' philosophy and robust, high-performance machines.
Model Evolution:
The 250/300/380 EXC and SX models were part of KTM's popular enduro and motocross lineage, evolving from earlier models with continuous improvements in engine performance, suspension, and chassis design. The 1998 models represent a specific generation within this evolution.
Production Period:
These engine platforms were produced in various iterations throughout the 1990s and into the early 2000s.
Historical Recognitions:
KTM's 2-stroke off-road motorcycles from this era were renowned in their respective classes (Enduro/Motocross) for performance and durability, often winning races and garnering praise in enthusiast publications. Specific awards for the 1998 model year are less common than general model segment recognition.
Enthusiast Ratings:
Highly regarded by riders for their potent engines, agile handling, and off-road capability. Often sought after by those seeking a powerful, no-nonsense dirt bike experience.
Emissions Certifications:
N/A (Off-road motorcycles of this era were generally not subject to stringent emissions certifications compared to street-legal vehicles.)
