Which Yamaha outboard is best for my boat and how should I choose the right model?

The best Yamaha outboard fits your hull's approved power and engine weight limits, handles your normal load comfortably, and matches your transom and controls. Start with the boat builder's specifications, then choose the engine version and propeller to suit how you use the boat.

Check power and weight limits

Find the builder's plate and handbook. The plate may show maximum power; the handbook or builder should confirm permitted engine weight and installation requirements. A heavier engine changes stern trim, cockpit drainage and handling, even if its horsepower is within the limit.

Never exceed the builder's maximum power or permitted engine weight. Have a suspect transom inspected before fitting a replacement engine.

Write down the boat's length, hull type, existing engine, fuel capacity and usual load. Include passengers, batteries, fishing equipment and watersports gear. An engine that performs well with one person may struggle with a family aboard.

• Tender or small displacement boat: Yamaha F2.5 to F6 models are sensible starting points where portability and modest speed matter.
• Larger tender or light open boat: consider the F8 to F25 range, checking lifting weight and whether you need electric start.
• Small planing fishing boat or RIB: F30 to F70 models are common candidates, with the choice depending heavily on hull weight and load.
• Heavier RIB, sports boat or fishing boat: F80 to F150 and larger engines may suit, but choose from the builder's recommended range.

Use these ranges to draw up a shortlist, not to choose horsepower by boat length alone. A sailing yacht auxiliary usually needs thrust and suitable gearing rather than enough power to plane. Ask about Yamaha's high-thrust FT models where available.

Match shaft length and weight

Check the required shaft length in the boat's installation information. Common nominal lengths are 15-inch short, 20-inch long and 25-inch extra-long; some larger installations use 30-inch shafts. Availability and suffix codes vary by model and market.

For a conventional transom installation, the anti-ventilation plate generally starts around the level of the hull bottom. Hull shape, transom setback and mounting brackets can change the correct height, so do not choose shaft length from a tape measurement alone.

A shaft that is too short can let the propeller draw air during turns or acceleration. Excessive immersion adds drag and spray. Sailing yachts also need enough immersion to keep the propeller working as the stern pitches.

Compare the published weight of the exact version you intend to buy. Electric start, power trim, shaft length and steering options can change it. When repowering, assess the complete installation, including batteries and equipment moved aft, rather than comparing bare engine weights alone.