Horizontal Crankshaft


From small vehicles to water pumps, from generators to construction equipment, this engine gives solid power and efficiency.

Horizontal Crankshaft

Reliability meets Intelligence

GX660 Features
  • Fuel economy is similar to fuel injection, with the simplicity of carburetion
  • Digital CDI ignition system with variable timing
  • Includes a rev limiter to protect against damage from over-revving
  • Two barrel inner-vent carburetor for more precise fuel metering
  • Insert style rod bearings
  • Hemispherical combustion chamber delivers rapid combustion
  • 9.3:1 compression ratio generates high-power output without the need for premium fuel
  • Forged steel crankshaft
  • Pressure-fed crankshaft bearings
  • Integrated cylinder and head
  • Racing-inspired forged steel connecting rods
  • High-capacity 36-blade cooling fan
  • Aluminum push rods with steel tips, lighter weight, lower vibration, and quieter operation
  • High-capacity pump facilitates consistent oil delivery
  • Dual cylindrical air filter
  • Large-diameter air intake for superior cooling
  • 3-Year Limited Warranty
  • Oil Alert®
  • Hour meter available
  • Conveniently located controls, with several configurations available based on user preference
  • Automotive-type spin-on oil filter
  • Automatic mechanical de-compression system
  • Variable ignition timing
  • CARB and EPA certified
  • No catalyst necessary
  • High-capacity charging systems
  • A variety of control box configurations
  • Hour meter
  • Dry fuel versions
Variable timing digital CDI ignition

GX270-390, V-Twin series

Honda’s Variable Timing Digital CDI ignition allows optimal ignition timing based on engine speed. The result:

  • Excellent starting,
  • High power output,
  • Reduced fuel consumption, and
  • Outstanding emissions performance.

An engine rev limiter is also incorporated to prevent over-revving.

Hemispherical combustion chamber

V-Twin Series

Honda’s hemispherical combustion chamber was inspired by our proven racing technology. It offers the highest V-Twin compression ratio on the market.

The power is transmitted through forged-steel connecting rods and a forged-steel crankshaft, supported by a full-pressure lubrication system.

  • 9.3:1 compression ratio generates tremendous power
  • Excellent combustion efficiency
  • Allows a radial configuration to create high volumetric efficiency
  • Places the spark plug near the center of the chamber for optimal flame travel

This means increased engine efficiency and more power to your application.

Oil Alert®

GX series, V-Twin series

Honda’s Oil Alert system helps to prevent engine seizure due to a low oil condition.

The system consists of an oil level sensor inside the crankcase. When the oil reaches a level that is too low for safe operation, the engine warns you or stops automatically.

Automatic mechanical decompression system

All engines

Honda’s automatic mechanical decompression system is designed to give you quicker, easier starts.

This system, which is connected to the camshaft, reduces compression by opening the exhaust valve slightly when the engine is being started. This reduces the amount of force needed to start the engine and improves starting performance.

The system disengages automatically after the engine starts to prevent any power loss during normal operation.

  • Service & Warranty

    You can rely on Honda dealers and Honda Genuine Parts.

    Keeping your Honda healthy is an imperative part of maintaining the quality, reliability and performance of your engine.

    Learn More
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