The company says that they are ideal for pontoons, aluminum bass and walleye boats, small center consoles, and inflatables. Honda’s redesigned BF40 and BF50 EFI engines’ patented BLAST technology dramatically improves Honda’s holeshot and acceleration 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, says the company. 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 Mikuni® Intake System, whose long intake tracks pair with BLAST technology for strong holeshots.
Fishing boats do not live by holeshots alone, 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, says Honda.
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 Closer Look Under the Cowling
The in-line 3-cylinder BF40 and BF50 EFI feature a Single Overhead Camshaft (SOHC) design that delivers the 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 ensuring an optimal air/fuel mixture across the rpm range.
Further contributing to the engines’ outstanding fuel economy is Honda’s exclusive Lean Burn Control, which pairs the ECU with an oxygen (O2) sensor to adjust the air/fuel mix 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 components are mounted near the top of the powerhead to help ensure that all are kept cooler and dryer. By extension, a camshaft-driven, automotive-style oil pump ensures long-term durability of critical engine components.
Important “Engine Alert” Monitors
The BF40 and BF50 EFI boast an Engine Alert System that uses visual, audio, and rpm reduction circuits to alert the operator to 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 messaging through Honda’s multi-function digital gauges or a special indicator built into the unit’s control box.
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 BF40 and BF50 EFI are available in 20- and 25-inch shaft models.
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.