Yamaha VF115LB 115HP VMAX SHO Mechanical Outboard 20″

Description

The Yamaha VF115LB pairs a 1.8-liter inline-4 DOHC engine with standard rotation, weighing 377 lbs dry. Built for low-transom configurations, the 20-inch shaft ensures ideal propeller depth and balanced tracking across heavy-duty fiberglass hulls navigating rough open ocean waters.

Running within a 5300-6300 RPM range, this offshore engine sustains cruising speeds across long tournament distances. The 2.15:1 gear ratio converts combustion force into a flat torque curve, so heavy boats get on plane without burying the stern under load. This Japan-built platform is engineered to reduce hull vibration during long-range deep-sea operations.

Technical Specifications of Yamaha VF115LB

• Electronic fuel injection uses a multi-point sequential track for strong thermal efficiency across all cylinders.
• A 35-Amp gross alternator generates enough power to keep house battery banks topped off.
• Remote mechanical control gives responsive vessel tracking adjustments.
• Power trim and tilt simplifies trailering and shallow-water operation by moving the lower unit clear.
• A 3.2-liter oil sump supports continuous lubrication during hard wide-open-throttle runs.
• The sport styling lower unit optimizes hydrodynamic flow and efficient standard clockwise propeller thrust.

DOHC High Performance Architecture

The 16-valve DOHC design treats the cylinder layout of this inline-4 block to optimize thermal efficiency, shaving response lag off the powerhead while improving volumetric efficiency under tournament conditions.

Sequential Track Fuel Induction

Electronic fuel injection sprays gasoline into the intake tracks for clean combustion on 87-octane fuel, giving immediate throttle response and reliable cold starts.

High Performance Sport Lower Unit

Oversized internal gears and a 2.15:1 gear ratio profile minimize underwater drag at high cruising speed, mitigating gear chatter and ensuring smooth power transmission during tight cornering.

Tournament Rigging Control Setup

Digital electronic control integrates with the mechanical helm components for reliable throttle tracking, coordinating with the internal engine loops to maintain crisp response.

Bass Boat Hull Match Application

High-performance bass boats, tournament bay boats, shallow flats boats, and sport aluminum fishing rigs in the 16-20 ft range are the target. The shaft delivers strong leverage and vibration dampening driving through chop.

Cowling Access And Lubrication

A multi-piece outer cowling gives fast access to critical checking points, cutting service time down. The drain plug keeps oil changes clean. Pro Tip from the Shop: verify tournament mechanical cables are adjusted tightly inside the rigging tray every season to prevent throttle slop from clipping top-end speed.