Yamaha F4, F5 and F6 are the smartest in their class

In the world of small portable four-stroke outboard engines, there's a surprising lot to consider. Storage, portability, ease of starting, tilt option and operation, performance, torque, even alternators and so on.

With this in mind, the Yamaha team drilled down into the needs of the typical small-outboard operator — those with dinghies, tenders, inflatables, small trailer yachts and watercraft — to design a range of class-leading 4hp, 5hp and 6hp one-cylinder four-stroke offerings.

Compact, lightweight and powerful were the three keywords on the drawing board of the Yamaha engineers assigned the task of creating the new F4, F5 and F6.

Utilising a 139cc one-cylinder engine, Yamaha has managed to provide class-leading displacement without additional weight.

A range of exclusive features, that increased capacity for greater performance, as well as the latest generation cowl design and graphics, have now created a staunch following for these powerful little Yammie portables.

NO OIL LEAKS AND EASY FUEL SYSTEM
The oil leak prevention system on the F4, F5 and F6 has been a bit hit. This ingenious innovation allows the owner to lay the engine on its front or either side without compromising the oil location for hassle free transport and storage. This matters to a lot of operators who store their 'kicker' on-board.

As fuel consumption isn't such a big issue on these inherently frugal little four strokes, an integrated 1.1lt fuel tank was considered the right size for the job. The handy built-in fuel tank helps reduce the engines' profile for storage, while the tank is see-through, making it easy to fill and easy to check the remaining fuel available.

In fact, the filler location of the internal tank has been specially designed at the front of the engine and tilted forward to allow more comfortable on-water refueling. This is no big deal, but for longer trips you can simply plug in an external tank (available as an option) and twist the two-way fuel tap to tap into a big supply if you want that.

Meantime, an oil check window allows the operator to check the oil level and condition at-a-glance for easy general maintenance and peace of
mind. Now, you are ready to go.

EASY STARTING
Starting is a snap. An in-built internal primer pump allows you to easily prime the fuel system from the internal tank for easy pull starting. This is aided by an auto-decompression device fitted to the camshaft. This system releases pressure in the cylinder when the manual pull start is engaged, allowing a much lighter pull starting experience.

Underway, the F4, F5 and F6 feature a three-step shallow-water-drive system that will be extremely useful for tackling Australia’s shallow rivers, estuaries and creeks. There is also a five-step trim adjustment that can be modified, depending on water conditions and boat load, for optimum engine performance. So you can get your tinnie up on the plane.

PORTABILITY AND MORE
Importantly, for convenient transport and mounting, Yamaha’s small four
strokes are fitted with an economically designed grasp on the front of
the engine and a large carry handle on the rear. The rear carry handle
is solid injection-moulded polypropylene, with a smooth finish to
deliver a secure and comfortable feel.

The achievement of a
perfect balance position from the carry handle is said to make Yamaha’s
portable engines easier to carry than competing products – even those
with slightly lighter weight. A parallel carry position means Yamaha’s
portable engines can be carried by a customer with their arm fully
extended without the skeg touching the ground.

Last but not least, a 12V-6Amp alternator with rectifier is offered as an option. This convenient option of a lighting coil and voltage regulator/rectifier provides a reliable 12V 6A power supply for running lights or charging batteries. This is a great feature if the owner plans to fish at night, or set up their boat with additional electronics.

The F4. F5 and F6 have now carved a reputation as the go-to outboards in their class. To top it off, they come with Yamaha's reputation for reliability and its national dealer backing. More at Yamaha Motor Australia's outboard engine landing page.

Specifications: F4, F5, F6
Engine Type: OHV, 1-cylinder
Displacement: 139cc
Bore x Stroke: 62 x 46mm
Recommended Max RPM: 4500-5500
Lubrication System: Wet sump
Fuel Management: Carb
Ignition: CDI
Starter System: Manual Choke
Alternator Output: 12V-6Amp with Rectifier Regulator (optional)
Operation Method: Tiller Handle
Trim & Tilt Method: Manual Tilt
Fuel Tank Capacity: 1.1 L
Gear Ratio: 2.08:1   
Dimensions Height: Short Shaft 440mm , long shaft 568mm
Weight: 27-28 kg
Yamaha and Dealer Listing: Yamaha Motor Australia.