Honda BF40 & BF50: Redefining Mid-Range Four-Stroke Performance

Honda Marine's redesigned its BF40 and BF50 horsepower (hp) outboard engines incorporate Electronic Fuel Injection as well as a host of Honda-exclusive technologies and consumer benefits.

The models afford boaters the fuel efficiency and quiet operation of Honda's legendary four-stroke outboard engine technology combined with light weight and powerful acceleration. Honda's exclusive Boosted Low Speed Torque (BLAST) system and a new high-performance gear case combine for a strong holeshot, while Lean Burn Control provides maximum fuel efficiency at cruise. And at 214 pounds, the engines are the lightest in their class.

Redefining Mid-Range Four-Stroke Performance
Ideal for pontoons, aluminum bass and walleye boats, small center consoles, skiffs, and inflatables, Honda's redesigned BF40 and BF50 EFI redefine four-stroke performance with the patented BLAST system.

Holeshot and acceleration are dramatically improved by advancing ignition spark timing to within one degree of the knock limit during "hammer down" acceleration. The Engine Control Module (ECM) then steps in to increase injector timing, creating a more potent air/fuel mixture. The resulting boost in available torque at low rpm contributes to a strong holeshot to get the boat up on plane quickly. The ignition spark timing is appropriately adjusted under slower throttle advancement, ensuring a leaner air/fuel mix and class-leading fuel efficiency. Further contributing to the pair's exceptional performance is a lightweight Mikuni® Intake System, whose long intake tracks pair with BLAST technology for strong holeshots.

Performance while fishing, of course, is not limited to top-end speed; slow trolling is also essential. The redesigned BF40 and BF50 EFI recognize a fifteen percent improvement in this area, with the ability to troll at 800 rpm.

The BF40 and BF50 EFI also feature Honda's all-new high-performance gear case. A longer anti-ventilation plate helps trap water flowing to the propeller to minimize porpoising, while a streamlined front and enlarged bullet reduce drag for enhanced acceleration and fuel efficiency. A front splash plate reduces spray from the hull bottom, helping to maintain a dry deck above.

A Closer Look Under the Cowling
The in-line 3-cylinder BF40 and BF50 EFI feature a Single Overhead Camshaft (SOHC) design that delivers an optimal air/fuel mixture for maximum torque and combustion efficiency. In addition, a Multi-Port Electronic Fuel Injection system (PGM-FI) accurately controls ignition timing and fuel flow during start-up to provide instant throttle response regardless of weather conditions. The system also helps improve overall fuel efficiency by maintaining an optimal air/fuel mixture across the rpm range.

Further contributing to the engines' outstanding fuel efficiency is Honda's exclusive Lean Burn Control, which pairs the ECU with an oxygen (O2) sensor to adjust the air/fuel mixture according to speed and load, maximizing efficiency in "cruise mode."

The engines' best-in-class 22-amp alternator (17 amps of battery charging), ignition, and other critical electrical components are mounted near the top of the powerhead to ensure that all are kept cool and dry. By extension, a camshaft-driven, automotive-style oil pump ensures long-term durability of critical engine components. The BF40 and BF50 EFI also meet NMEA 2000 standards, providing users full compatibility with a host of electronic devices.

The BF40 and BF50 EFI boast an Engine Alert System that uses visual, audio, and rpm reduction circuits to alert the operator of conditions that contribute to engine damage, such as overheating, low oil pressure, and over-revving. Tiller models feature a new 4-lamp warning system built into the tiller handle, while remote control models deliver alerts via messages through Honda's multi-function digital gauges or a special indicator built into the unit's control box.

Both engines feature Honda's exclusive double-sealed and multi-layered Four-Front Corrosion Protection (paint) System, as well as several other features designed to minimize damage caused by the harsh marine environment. A unique one-touch anode check system and improved waterproofing inside the engine cover and gear case are just a few of the innovative features Honda has added to ensure the motors' long-term durability.

In addition to improved fuel efficiency and performance characteristics, the BF40 and BF50 EFI also incorporate a number of features designed to facilitate maintenance. An automotive-type oil filter and color-coded oil fill and dipstick simplify fluid level checks and changes. Additionally, both are compatible with Honda's HDS portable diagnostic system to facilitate on-water service.

The BF50 EFI is available in 20- and 25-inch shaft models, while the BF40 EFI is offered in a 20-inch shaft length. All new Honda outboard engines sold for recreational use offer an industry-best True 5-year, non-declining limited factory warranty that is the same on the last day as it is on the first.

Honda Marine pioneered four-stroke engine technology, setting a new benchmark for fuel efficiency, quiet operation, and low emissions. Honda's outboards share the same unparalleled durability, quality, and reliability of its legendary automobiles. With models ranging from 2 to 225 horsepower, Honda Marine's full line of current production models meets rigorous California Air Resources Board (CARB) 3-Star standards, ensuring their availability and regulatory compliance in all 50 states.

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Editor's Note:

Honda Marine, a division of American Honda Motor Co., Inc., markets a complete range of outboard marine engines. Its comprehensive product line is powered exclusively by four-stroke engines.

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