Honda has been developing and rapidly deploying various environmental and energy technologies to share the joy of mobility with people around the world. As a global company, we strive to satisfy mobility needs while also reducing environmental impact from our products to realize a sustainable motorized society.

BF250 four-stroke outboard engine

Honda’s BF250 (250 horsepower) four-stroke outboard marine engine, released in October 2011, boasts best-in-class fuel economy and excellent power performance. The BF250, which is based on the BF225 (225 horsepower), incorporates a number of cutting-edge technologies, including a newly developed 3.6-liter V-6 Variable Valve Timing and Lift Electronic Control® (VTEC®) engine, and the world's first1 marine direct-air, dual-circuit induction system of its type on a production outboard, enabling the BF250 to achieve high performance as well as Lean Burn Control during cruising.2 　

Setting the air intake circuit and exhaust heat circuit independently with the direct-air, dual-circuit induction system allowed us to lower the temperature of intake air, which is essential to improving engine power. The intake circuit draws outside air from the air intake in the top part of the engine cover, sends it through a circuit set up within the engine cover, where moisture is removed, and then sends it to the engine. In the waste heat circuit, air drawn from the front of the engine cover circulates and cools critical engine components and the alternating current generator, and is then removed by a top-mounted cooling fan. This system delivers cooler, denser air for better combustion than conventional induction systems.

In addition, employment of the O2 sensor-equipped PGM-FI3 (Programmed Fuel Injection system) enabled a Lean Burn Control during cruising, and allowed for the best-in-class fuel economy.

In terms of exhaust gas, the BF250 complies with the latest U.S. Environmental Protection Agency (EPA) regulations, California Air Resources Board (CARB) 3-Star standards, and other regulations, ensuring its regulatory compliance in numerous nations.

The National Marine Manufacturers Association (NMMA) named the all-new Honda Marine BF250 engine as a recipient of the 2011 IBEX Innovation Award for outboard engine technology, and presented the award at the International Boat Builder's Exhibition and Conference (IBEX) at the Kentucky Exposition Center in Louisville, Kentucky, on October 17-19, 2011. The IBEX Innovation Award is the industry's highest honor for innovative and technological advancement. Assessment is based on strict inspections by a panel of judges from Boating Writers International (BWI), an international organization of marine journalists. The award presented to the Honda BF250 shows that the world's first marine direct air dual circuit induction system on an outboard has been recognized as innovative technology.

Note 1:

Honda internal research (as of October 31, 2011)

Note 2:

Refers to navigation speed scope where rotation is maintained at 50-80% of full throttle.

Note 3:

PGM-FI (Programmed Fuel Injection System) is a registered trademark of Honda.

BF250 four-stroke outboard engine

The direct air dual circuit induction system

2011 IBEX Innovation Award winner logo