Honda BF115JK1XDA 115HP – iST 25″ Shaft Standard Rotation

Honda BF115JK1XDA 115HP iST Digital Silver

The Honda BF115JK1XDA pairs a 2.4L DOHC inline 4-cylinder engine with the iST digital system, delivering the highest displacement in the 115HP class. The 25-inch extra-long shaft is built for high-transom offshore bay boats and deep-V cruisers in Mulmarine’s digital marine engines lineup. The 16-valve DOHC design gives smooth power delivery and reduced vibration.

The Intelligent Shift & Throttle (iST) system gives fly-by-wire command across a 4500-6000 RPM range. The BF115JK1XDA runs a 2.14:1 gear ratio and a 55-Amp alternator, suited to vessels with high-draw electronics and multi-battery systems, with effortless digital engine synchronization.

Massive 2.4L DOHC Displacement

The 2.4-liter block gives higher torque and smoother power delivery than standard 115HP competitors with smaller displacements, reducing mechanical stress and vibration.

Intelligent Shift & Throttle (iST)

The iST system gives a cable-free operating experience through digital signal processing, allowing precise vessel positioning and instant response to input.

Extra-Long 25-Inch Shaft Authority

Calibrated for 25-inch transom heights, this shaft keeps the lower unit deep enough to prevent ventilation in heavy following seas, giving stable tracking on offshore bay boats.

Advanced BLAST Torque Technology

Honda’s BLAST technology advances ignition timing during rapid acceleration, cutting the hesitation common in four-stroke outboards for a strong hole-shot.

Lean Burn Control ECOmo

Honda’s ECOmo system adjusts the air-fuel mixture based on real-time speed and load, running a leaner mixture at cruising speed to maximize fuel economy.

High-Output 55-Amp Charging

The 55-Amp alternator (40 Amps charging) supports navigation radar, large multi-function displays, and high-draw livewell pumps without draining the starting battery.

Honda 5-Year Factory Warranty

This engine carries Honda Marine’s 5-year non-declining limited warranty. Pro Tip: use Honda’s genuine 10W-30 marine oil and regular fresh-water flushing to protect the internal 2.4L block.