Yamaha 130B

Following a trend by manufacturers in the mid-'90s to provide more of a horsepower range between V4 and V6 outboards, in 1996 Yamaha de-rated its long running 140 to 130hp and created the 130B. Long, extra-long and counter-rotating variants were made available.

The 130B is an uprated version of the 115C, which started life as a 50:1 premix motor in 1983. This model was reintroduced as a CV115 in 1992 and discontinued in 2000, which was a shame, as a mate who has owned two of these motors found them completely reliable.

Although the 130B is still a "first generation" two-stroke and retains electrically operated chokes and mechanical ignition timing advance, its inherent simplicity ensures a long service life. The two dual-throat carbies rarely need balancing and the motor has standard engine protection features such as a rev limiter and engine overheat/low oil level alarms. The 20amp alternator produces 16amp at only 1000rpm.

Provided different types of oil are not mixed together, the oil injection system, which varies fuel/oil ratios from 50:1 at Wide Open Throttle down to 200:1 at Dead Slow Troll, is relatively trouble-free. And with the oil being injected at the reed valves, the carbies run straight petrol, eliminating the need to run the motor dry before extended periods of disuse. Research conducted recently by predominantly two-stroke dealers has found that running dry a two-stroke can lead to the piston rings scoring the cylinder walls.

As with the V6 models, the oil injection system has two oil tanks: one undercowl, which is kept topped up, and the main in-boat tank, which holds 10.5lt.

Tested on two very different Haines Hunter hulls, both demo motors provided excellent performance, had low vibration levels and were quiet for carburetted two-strokes. Both motors started quickly hot or cold, warmed quickly from cold and, running on a break-in mix of 50:1 in addition to the oil-injection, emitted oil smoke only on starting and below 1000rpm.

On a 535BR Carnival bowrider the first 130B provided all the power you'd need on this hull for family boating and social skiing. Spinning a 19in pitch stainless steel prop and pushing a total of 1000kg including two adults, the Yammie planed us cleanly at 29.2kmh on 3000rpm and cruised quietly at 44.4kmh on 4000rpm. And at 4500rpm prop ventilation occurred only through tight figure eights.

Across a chop to 40cm, the WOT average was 78.0kmh on 6100rpm. Although the second hull - a 570SF Champion half cabin - weighed considerably more, the 130B handled it with ease. Again spinning the 19in prop but pushing a total of 1200kg including two adults and one child, the 130B trolled us quietly at 4.8kmh on 600rpm and averaged 11.9kmh on 2000rpm, sufficient for trolling offshore.

A clean plane was achieved at 31.2kmh on 3100rpm and at 4000rpm the 130B cruised effortlessly at 46.0kmh consuming 24lt/h. Based on an average fuel/oil ratio of 120:1 at these revs, the in-boat oil tank provides more than 50 hours of operation! However, through tight figure eights at 4000rpm, there was a fair amount of prop ventilation.

Surprisingly for a heavier hull, over the same height of chop the Yammie still averaged 6100rpm at WOT, but greater prop slip reduced the speed to 72.3kmh, where the motor consumed 56lt/h.

Despite the undercowl oil tank, powerhead access is still very good and the spark plugs, bowl-type fuel and oil filters and carbie linkages are easily reached. Yamaha recommends servicing the 130B every 50 hours or six months for the first two years after the initial 10-hour service, then every 100 hours or once a year. This also applies to waterpump impeller replacement.

Before the introduction of Yamaha's YDC30 alloy in the early '90s, the 115/140 model was prone to cooling water passage corrosion. But since the introduction of the YDC30, I've received no reports of corrosion in this model, and that includes the 130B.

Although it's "dirty" compared to the direct Honda competition, Yamaha's 130B suits saltwater boaters who want a combination of performance, fuel efficiency and low purchase and running costs.