Yamaha LXF450XSA2 450HP XTO Counter-Rotation DEC 25″

Description

The Yamaha LXF450XSA2 pairs 450HP with a 25-inch shaft, built with counter-rotation gearing for multi-engine offshore boats. The 5.6-liter V8 platform displaces 5559cc while holding a dry weight of 963 lbs — lighter than the 35-inch versions, since less shaft length means less material. Built for mid-transom configurations, the 25-inch shaft keeps propeller depth and tracking balanced on heavy-duty fiberglass hulls in rough open water.

Peak output holds through a 5000-6000 RPM band, and this offshore engine sustains cruising speed across long tournament distances on that range. The heavy-duty 1.79:1 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 run smoothly during long-range deep-sea operations.

Technical Specifications of Yamaha LXF450XSA2

• High-pressure direct fuel injection atomizes gasoline at 2900 PSI for efficient combustion across all cylinders.
• A 102-Amp gross alternator generates enough power to keep house battery banks topped off.
• Integrated electric steering replaces complex hydraulic lines with instant digital response at the wheel.
• TotalTilt simplifies trailering and shallow-water operation by tilting the lower unit completely clear.
• A 7.8-liter oil sump supports continuous lubrication during hard wide-open-throttle runs.
• The counter-rotation gearcase balances propeller torque to maintain tracking on multi-engine express cruisers.

32-Valve V8 Block

The sleeveless 32-valve DOHC V8 is engineered to shave weight from the powerhead while managing heat dissipation under severe offshore conditions — important given how much work this block does across a full day offshore.

Direct Fuel Injection System

Direct fuel induction sprays gasoline straight into the combustion chambers at 2900 PSI for cleaner combustion cycles. That delivery system is what keeps throttle response immediate and cold starts reliable in changing early-morning coastal conditions.

Counter Rotating Gearcase Profile

Oversized internal gears and a streamlined lower unit maximize hydrodynamic thrust while canceling out steering pull on multi-engine setups. That mechanical setup keeps lower-unit chatter down and propeller tracking steady when backing down on a fish.

Digital Power Management Setup

Digital electronic control integrates with the electric steering system to handle house power needs automatically, supplying up to 96 net amps to run multifunction displays and gyro stabilizers without draining the batteries.

Advanced Fiberglass Hull Application

Large offshore center consoles, multi-engine express boats, and sports cruisers in the 30-45 ft range are the target application for this 25-inch outboard. The mid-length shaft delivers strong leverage and vibration dampening driving through steep waves.

Cowling Access And Lubrication

A multi-piece outer cowling gives fast access to critical checking points, cutting service time down. The drain plug location keeps oil changes clean rather than messy. Pro Tip from the Shop: pull the gear lube plugs at the dock and use a lower unit pump to push fresh oil from the bottom up, keeping air pockets out of the gear housing.