2017 Yamaha 2.5LMHB

Engine Information
Propulsion:Outboard Prop

The sun just broke the horizon, but your day began hours ago—the second you started your trusty Yamaha Portable. Maybe you’re skimming the marsh in a jon boat during duck season, pushing a sailboat ‘til the wind kicks up or hopping to the cuddy on a tender. Wherever the day takes you, these nimble, lightweight, efficient portables are up for the ride. Available in a range of horsepower from 20 all the way down to 2.5, these 1- or 2-cylinder dynamos provide big performance in streamlined designs.

Here’s why so many boaters carry Yamaha reliability with them, wherever they go:

Incredibly Light
Yamaha Portables are incredibly light, weighing as little as 37 pounds. Talk about punch you can pack.

Easy to Carry
Select models feature built-in front and rear carry handles for maximum portability. Plus, recent re-designs have made several of our portables, well, even more portable. The F9.9 is 12% lighter than previous designs, and we’ve trimmed 23 pounds from our F6.

Max Maneuverability
Our 5-Step Trim Adjustment and 3-Step Shallow Water Drive System (on select models) protects your propeller in skinny water, making these pintsized powerhouses extremely maneuverable and getting you where you need to go.

Fuel Efficiency
The smaller the motor, the less fuel it consumes, true. However, one of Yamaha’s portables actually made it into the Guinness Book of World Records for the most miles traveled on one gallon of gas, going 67.27 continuous statute miles.

Smart Innovation
Our Easy Oil Retention System allows the F6, F4 and F2.5 to be stored on their sides or front grip without oil leakage. Our F15 and F20 designs feature a water-cooled fuel pump, boosting power and preventing warm weather starting issues like vapor lock.

Yamaha Portables just seem to get lighter, stronger and smarter, year after year. Let’s take a look at their ever-advancing engineering.


  • Engine Type: One-Cylinder
  • Displacement: 72cc/4.4ci
  • Bore x Stroke: 54 x 31.5mm/2.13 x 1.24in
  • Full Throttle RPM Range: 5250-5750
  • Horsepower Rating at Prop Shaft: 2.5hp at 5500rpm
  • Compression Ratio: 8.8:1
  • Fuel Induction: OHV(Overhead Valve)
  • Starting Method: Manual
  • Ignition: TCI Microcomputer
  • Degree of Trim: 4 positions
  • Degree of Tilt: 79°
  • Exhaust: Above propeller
  • Cooling: Water/Thermostatic Control
  • Drive: Forward, Neutral
  • Gear Ratio: 27:13/2.01:1
  • Shaft Length:Short=15″, Long=20″
  • Recommended Fuel: Regular Unleaded/Minimum Pump Octane 87
  • Recommended Oil: Yamalube® 4M
  • Spark Plug: CR6HSB
  • Weight: 20kg/40lbs
  • midrange-warranty