For whatever reason, four-stroke outboard builders have shied away from the number 100, which is odd because it’s so even. In all four-stroke outboard lines, the jump is incremental until you get to 90 hp, after which it leaps to 115 … until Honda unveiled its newest, the BF100. Here’s another unique Honda engine number for you: 27.8 million, which is the total number of engines it built worldwide in 2015, encompassing the entire spectrum of its products, including cars, motorcycles, lawnmowers, snow blowers, jets — you name it. Honda built its first four-stroke outboard in 1964, the GB30, so the company has had a little practice at it. This motor, in particular, is well sorted out, since it’s based on an L15-Series engine that also powers its sporty compact car the Fit.
The BF100 shares the same block as the BF90, so there’s no weight penalty for making the deca-leap, and it’s among the lightest of the 90-class four-stroke outboards, weighing 359 pounds; only Suzuki’s 90 weighs less, at 341 pounds. Like the other four-stroke manufacturers in its class, Honda employs an inline, single overhead cam (SOHC) four-cylinder configuration, but it has the least amount of displacement at 1.5L (1496 cc, to be exact). To make up for this, it uses a technology called Variable Valve Timing & Lift (VTEC) that’s shared with Honda’s flagship model, the BF250. At low speeds, it uses a milder cam configuration that features a low-lift, short-duration intake valve opening cycle, but at higher speeds, a synchronizing piston engages and it changes into more of a racing cam profile that keeps the intake valves open longer for more power when called for.
Honda claims up to a 20 percent increase in fuel economy thanks to its Lean Burn Control technology, which uses an ECU computer brain to detect when load is reduced and reduces the air/fuel mixture to squeeze every last drop out of a gallon of gas without compromising performance. Its reliance on 93 octane fuel to make 100 hp tends to negate the fuel savings, though, as most non-supercharged outboards only need 87 octane to achieve their horsepower rating.
Anglers will love its Variable Speed Trolling feature, which allows drivers to dial in the perfect presentation speed in 50 rpm increments when idling along, from 650 up to 1000 rpm. And for fishermen who prefer tiller steering, Honda offers a three-position tiller arm, so anglers can stand and steer in comfort. It’s center mounted, extra long and features up-front shifting on the handle itself, so drivers don’t have to reach around to the side of the engine to shift.
Boaters who use a lot of electronics, such as anglers who have twin GPS/fishfinder displays, will love its ability to produce charging electricity. It develops 44 amps, overall, and its 35 charging amps ties it with the Mercury 90 to be the highest in its class.
The BF100 is an easy motor to maintain thanks to features such as a built-in flush port that’s designed to work without the motor running, which neighbors will love. It also has a front-mounted oil filter for easy do-it-yourself changing. Mechanics will appreciate its screw-type valve adjusters that don’t need shims to ensure proper clearance at its 200-hour scheduled maintenance check.
We tested the BF100 on several different boats, including an Alumacraft 1860 Bay Tunnel Boat and two pontoons, the Premier 220 SunSation and the Qwest LS818. It comes in a 20- and 25-inch shaft length, so it fits a wide range of boats, and with a low 2.33:1 gear ratio it can swing a bigger diameter prop to move more water.
One of the features that shined during our performance test was BLAST, which helps boats get on plane quickly. It’s an acronym for Boosted Low Speed Torque, and it only kicks in if you jam the throttle lever quickly, as we did on the Alumacraft. Doing so aggressively advances the spark, opens the throttle body and enriches the air/fuel mixture; it helped the 1860 Bay Boat get on plane in just 2.4 seconds. The BF100 propelled it to 30 mph in 7.3 seconds and pushed it a top speed of 40.2 mph as it bumped up against the rev limiter at 6300 rpm.
Honda’s hallmark is its reliability, and the BF100 is backed up by a True 5 warranty, which is the longest in the marine industry. This non-declining warranty means it’s the same on day one all the way to its last day, five years later. And it’s fully transferable, which helps keep its resale value high.