2017 Yamaha F8 F8SMHB Outboard Motor

Yamaha's 2017 F8 F8SMHB sits on the short, 15-inch (S) shaft rather than the longer L option, running the same 197 cc twin-cylinder block at 87 lbs dry, two pounds lighter than the longer-shaft F8LMHB.

Confirming fit

The L-shaft version of this motor will not sit correctly on a shorter transom, so match the 15-inch figure to the boat before ordering. Centers for mounting sit 28.6 inches apart; tilt reaches 78 degrees across 4 trim positions, and steering travels 45 degrees from center in either direction.

Specs at a glance

Bore is 2.20 inches and stroke is 1.57 inches, at 8.8:1 compression. This is a manual-start motor with a 6-amp alternator built in, and Yamaha calls for regular unleaded at a minimum of 87 octane with about 0.8 liters of oil. Exhaust exits through the propeller, and Yamaha specifies a BR6HS spark plug with ethanol content capped at 10 percent. A dynamic balancer and a tuned intake manifold keep the twin-cylinder block smooth, and the carburetor is factory-tuned for its emissions rating.

What is the emissions rating? A 3-star C.A.R.B. rating, the same as the other small four-stroke portables. Where does it redline? Full throttle lands near 6000 rpm. Does it have an electric starter option? No, this trim is manual-start only.