40 - 50 HP


Ready to take you to great places. Like the head of the class.

The BF40 and BF50 are an outstanding combination of Honda’s legendary four-stroke engineering and our latest outboard innovations. The result? The lightest, most compact engines in their class. And because they are from Honda, they’re loaded with the unparalleled features and technology you want.

Like BLAST (Boosted Low Speed Torque). It’s activated by a quick movement of the throttle for vastly improved hole shots.

Programmed Electronic Fuel Injection, for easy starts, instant throttle response, slower trolling speeds, and overall better fuel economy.

Lean Burn Control stretches your gas even further by allowing a leaner air-to-fuel mixture.

Put it all together, and you’ll l find that the BF40 and BF50 aren’t just at the head of the class. They’re in a class by themselves, redefining mid-range four-stroke performance.

Reliable, efficient 4-stroke design

World-renowned Honda quality combines proven reliability and superior fuel efficiency, with no oil mixing.

Meets NMEA 2000 standards - on-board connectivity

NMEA 2000 protocols allow engine data to be displayed on NMEA 2000 compliant dashboard electronics, like sonar and GPS.

Lean Burn Control® - Superior fuel efficiency

Lean Burn Control® increases fuel efficiency by allowing combustion to operate on a leaner air/fuel mixture. At cruising speed, this engine runs on as much as 20% less fuel* than others in its class.
*Based on the EPA's Specific Fuel Consumption Mode.

Learn More

BLAST® System - improves acceleration at low speeds

Boosted Low Speed Torque, or BLAST, improves acceleration at low speeds. A quick movement of the throttle control activates the BLAST® system, advancing the ignition curve aggressively. "Hole Shot" is vastly improved as more horsepower gets the hull up on plane quicker.

Learn More

Programmed Fuel Injection - Powerful performance

Programmed Fuel Injection delivers the precise amount of fuel/air to each cylinder. The result is easy starts and instant throttle response with superior fuel efficiency.

Superior Battery Charging - More usable power

There's always plenty of electric power with the 40 and 50hp. Honda’s innovative technology enables these engines to put out nearly twice as many charging amps as the competition’s.

Learn More

High Performance Gearcase - gets you going faster

Designed to get you going faster, the BF40 and 50's gearcase reduces drag, greatly reduces hull porpoise and minimizes spray, thus increasing acceleration and top speed.

  • A longer anti-ventilation plate helps trap water flowing to the propeller to minimize porpoising
  • A streamlined front and longer bullet reduce drag for enhanced acceleration and fuel efficiency
  • A front splash plate reduces spray from the hull bottom, maintaining a dry deck above.

3 Position Tiller Handle - comfortable and easy to use

Adjusts to a comfortable angle for easiest hull manueverability.

Engine Alert System - Keeps you informed

Audio and visual cues combine with RPM reduction circuits to alert the operator of overheating, low oil PSI and over-revving to prevent engine damage.

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.

4-Front Corrosion Protection System - Fights the elements

A patented, "Double Sealed" multi-layered paint process. Sacrificial anodes and stainless steel technology, along with waterproof connectors, all enhance corrosion protection.

Learn More


Because of Honda’s elegant design, the BF40 and 50 are the lightest engines in their class. Perfect for aluminum boats, inflatables, skiffs and flats boats.

Ultra Low 3 Star CARB Emissions

Environmentally conscious technology. All Honda Marine engines exceed the highest CARB 3-Star rating to meet the rigorous California Air Resource Board's standards.

True 5 Warranty

Honda's True 5 Warranty is the best in the business. This transferable, non-declining warranty is the same on the first day as it is on the last.

Learn More

Center Mount Tiller - Easier control

The ergonomically designed tiller handle is longer for improved handling. Adjustments for throttle and steering friction allow easier control. Up front shift lever, PTT switch, and engine alert lamps provide added convenience.

Power Trim/Tilt

Allows you to trim the unit for maximum performance and handling.
Trim Range: - 4° to +16°
Tilt Range: 63°

Fresh Water Flushport

Flushes debris and saltwater out of the engine, extending the life of the outboard.

Easy Maintenance

Easy access side-mounted oil filter and oil fillers simplify maintenance, while "screw-type" valve adjusters reduce maintenance costs.

Offset Crankshaft Design - better performance

Honda's exclusive crankshaft design locates the powerhead directly over the transom pivot point. This has two effects. It reduces vibration and improves performance and handling. It also provides for a very compact design.

Non-Linear Mounting System - smoother operation

Patented non-linear rubber mounts provide smoother operation at all engine speeds.

Mikuni Intake System - better performance

The lightweight Mikuni long tube intake track system helps build low end torque.

Fisherman Friendly 800 RPM Trolling

Fishermen will appreciate the low trolling speed of the BF40 and 50.

Built-In Pitot Tube

Built-in pitot tube in the gear case eliminates the need to drill holes in your boat for installation.

Available in 20 and 25 inch shaft models


Type4-Stroke SOHC, 3 Cylinder, 2 Valves/Cyl.4-Stroke SOHC, 3 Cylinder, 2 Valves/Cyl.
Displacement808 cc (49.4 cubic inches)808 cc (49.3 cubic inches)
Bore & Stroke70 mm x 70 mm (2.8 x 2.8 inches)70 mm x 70 mm (2.8 x 2.8 inches)
Full Throttle RPM Range5,000-6,000 RPM5,500-6,000 RPM
Rated Power40 HP @ 5,500 RPM50 HP @ 6,000 RPM
Cooling SystemWater CooledWater Cooled
Fuel DeliveryProgrammed Fuel InjectionProgrammed Fuel Injection
Ignition SystemMicroComputer ProgrammedMicroComputer Programmed
Starting SystemElectricElectric
ExhaustThrough HubThrough Hub
LubricationWet SumpWet Sump
Trim Range-4° to +16°-4° to +16°
Tilt Range63°63°


Gear Ratio2.08:12.08:1
Gear ShiftF-N-RF-N-R


Alternator with voltage regulator (Electric Start)22-Amp (275 watt)22-Amp (275 watt)
Battery Charging Power17 Amps17 Amps
Power TiltNANA
Power Trim & TiltAvailableAvailable
Gas Assisted TiltAvailableAvailable
Oil Pressure AlertStandardStandard
Temperature AlertStandardStandard
Speedometer PickupStandardStandard


Overall Width372 mm/14.7 inches372 mm/14.7 inches

Transom Height

L Type508 mm/20 inches508 mm/20 inches
X TypeNA635 mm/25 inches

Dry Weight

L-Type97 kg/214 lbs.97 kg/214 lbs.
X-TypeNA101 kg/223 lbs.
Transom Ht.20"20"
Remote ModelX
Tiller IncludedX
iST- Electronic Shift & Throttle
Electric StartXX
Charging System17A17A
Prop Included
Power Thrust
Power Tilt & TrimX
Gas AssistX
Transom Ht.20"25"
Remote ModelXX
Tiller Included
iST- Electronic Shift & Throttle
Electric StartXX
Charging System17A17A
Prop Included
Power Thrust
Power Tilt & TrimXX
Gas Assist