Honda BF90HP powering a RIB
Honda Marine’s BF75 and BF90 afford boaters the fuel efficiency and
quiet operation of Honda’s legendary technology combined with the
lightweight and explosive acceleration traditionally associated with
two-stroke outboards. The pair’s 1.5-litre, in-line 4-cylinder engine
boasts Honda’s exclusive Boosted Low Speed Torque (BLAST) system,
Variable Valve Timing and Electronic Lift Control (VTEC™ – BF90), Lean
Burn Control, and Three Way Cooling.
BLAST Off
Ideal for smaller speedboats, centre consoles, inflatables, pontoons and
skiffs, Honda’s BF75 and BF90 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 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.”
Derived from racing and first appearing on the Acura NSX sports car,
VTEC™ (BF90) utilizes mild cam lobes to operate the intake valves at low
rpm, and then engages a high-output lobe for high-rpm operation. The
resulting boost in available power provides outstanding mid-range
acceleration.
Further contributing to the pair’s explosive performance is Honda’s
high-performance gear case. A longer anti-ventilation plate helps trap
water flowing to the propeller to minimize porpoising, while 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, and a 2.33:1 gear
ratio affords the use of 13- to 14-inch diameter propellers for heavier
loads.
Honda BF75HP
The engines’ best-in-class 44-amp alternator (35 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.
High Performance in a Durable Package
To ensure long term durability, Honda engineers designed the first
individually-controlled cylinder cooling system for outboard engines –
Three Way Cooling. The system reduces engine heat by allowing the
cylinder head to run slightly cooler than the cylinder block, greatly
reducing engine wear.
A Single Overhead Camshaft (SOHC) design uses dual intake valves to
deliver the optimal air/fuel mixture for maximum torque and combustion
efficiency. In addition, a Multi-Port, Programmed Electronic Fuel
Injection system (PGM-FI) accurately controls ignition timing during
start-up to provide instant throttle response and outstanding fuel
efficiency.
Top-mounted electronics are a standard feature on both engines. The
alternator, ignition, and other critical 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 promotes
long-term durability of critical engine components.
Honda BF75/90 Cover Off
The BF75 and BF90 boast an Engine Alert System that uses audio and
visual cues, as well as rpm reduction circuits to alert the operator of
conditions which can contribute to engine damage, such as overheating,
low oil pressure, and over-revving. A freshwater flushport functions to
flush debris and salt water out of the engine, while Honda’s patented
4-Front Corrosion Protection System features a double-sealed,
multi-layered paint process – both features extend the life of the
outboards in harsh marine environments.
The BF90 is available in both 20- and 25-inch shaft models, while the
BF75 is offered in a 20-inch shaft length. All new Honda outboard
engines sold for recreational use offer an industry-best True 3-year,
non-declining limited factory warranty that is the same on the last day
as it is on the first.
Technical Specifications: Honda Marine BF75
| ENGINE |
| TYPE |
Four-Stroke In-line 4-Cylinder |
| DISPLACEMENT |
1,496cc (91.3 cubic in) |
| BORE & STROKE |
73 x 89.4 mm (2.87 x 3.52) |
| FULL THROTTLE HP RANGE |
4,500 – 5,500 RPM |
| HP RATING AT PROPSHAFT |
75HP @ 5,500RPM |
| VALVE TRAIN |
SOHC |
| VALVES PER CYLINDER |
4 |
| FUEL DELIVERY |
Programmed Electronic Fuel Injection (PGM-FI) |
| IGNITION SYSTEM |
Microcomputer Controlled |
| STARTING SYSTEM |
Electric |
| LUBRICATION |
Wet Sump |
| COOLING SYSTEM |
Water Cooled |
| ALTERNATOR |
44 Amp (546 watts) |
| BATTERY CHARGING POWER |
35 Amp (433 watts) |
| TRIM RANGE |
-4° to +16° |
| TILT RANGE |
68° |
| DRIVE |
| GEAR RATIO |
2.33:1 |
| GEAR SHIFT |
F-N-R |
| PROPELLER |
Optional |
| DIMENSIONS |
| TRANSOM HEIGHT(S) |
(L) 508 mm |
| DRY WEIGHT (TILLER) |
(L) 171 kg |
| DRY WEIGHT (REMOTE) |
(L) 165 kg |
Technical Specifications: Honda Marine BF90
| ENGINE |
| TYPE |
Four-Stroke In-line 4-Cylinder |
| DISPLACEMENT |
1,496cc (91.3 cubic in) |
| BORE & STROKE |
73 x 89.4 mm (2.87 x 3.52) |
| FULL THROTTLE HP RANGE |
5,300 – 6,300 RPM |
| HP RATING AT PROPSHAFT |
90HP @ 5,500RPM |
| VALVE TRAIN |
SOHC |
| VALVES PER CYLINDER |
4 |
| FUEL DELIVERY |
Programmed Electronic Fuel Injection (PGM-FI) |
| IGNITION SYSTEM |
Microcomputer Controlled |
| STARTING SYSTEM |
Electric |
| LUBRICATION |
Wet Sump |
| COOLING SYSTEM |
Water Cooled |
| ALTERNATOR |
44 Amp (546 watts) |
| BATTERY CHARGING POWER |
35 Amp (433 watts) |
| TRIM RANGE |
-4° to +16° |
| TILT RANGE |
68° |
| DRIVE |
| GEAR RATIO |
2.33:1 |
| GEAR SHIFT |
F-N-R |
| PROPELLER |
Optional |
| DIMENSIONS |
| TRANSOM HEIGHT(S) |
(L) 508 mm |
| (X) 635 mm |
| DRY WEIGHT |
(L) 166 kg |
| (X) 172 kg |
