铃木(Suzuki) 4冲程 DF90-80-70P参数表    铃木(Suzuki) 4冲程 DF90-80-70P外观    铃木(Suzuki) 4冲程 DF90-80-70P使用照片            铃木(Suzuki) 4冲程 DF90-80-70P内部结构  The making of a compact outboard  Suzuki’s engineers are well known for their ability at
reducing the size of the outboard. Their skills have created
some of the most compact four-stroke outboards in their
respective classes. Taking a fresh approach to the
DF70/80/90, every part and component has been designed
from the ground up. Applying the knowledge and technical
advancements gained over the last ten years they have
succeeded again at reducing outboard size and weight.  Offset Driveshaft  Pioneered with the first generation DF90, Suzuki’s offset
driveshaft has played an effective role in reducing the size
of the outboard. The design uses intermediate reduction
gearing to position the crankshaft in front of the driveshaft,
moving the outboard’s center of gravity forward for better
weight distribution on the transom. It also provides
improvements in power performance,
balance, and vibration
reduction.
Combining the offset driveshaft
with a newly designed powerhead,
Suzuki engineers have created an
outboard that is about 7.5cm (3
inches) shorter than the original
DF90 and up to 23cm (9 inches)
shorter than competitive models
making the new DF90 the most
compact outboard in its class. Its
compact design facilitates installation
on a wider range of boats,
and offers more room around the
transom for fishing and other
activities.    DOHC 4-Valve Engine
The DF70/80/90 benefit from Suzuki’s unrivaled experience
in the design and manufacture of motorcycle, automotive,
and marine engines. Drawing upon their past advancements
and achievements, Suzuki engineers have provided these
new outboards with advanced engineering that delivers high
power output, performance, fuel economy, and efficient
operation.
Starting with an in-line 4-cylinder block, Suzuki designed an
all new, more compact dual overhead cam (DOHC) powerhead
with four valves per cylinder. Its design has reduced
the overall size of the outboard while providing high performance
power. Power is delivered via a two-stage mixed cam
drive system consisting of gears that transfer power
between the crankshaft and the drive shaft, and a chain that
delivers power from the drive shaft to the camshaft.    Two-Stage Gear Reduction
To take maximum advantage of the power produced by
these high performance engines, Suzuki engineers have
utilized a two-stage gear reduction ever since the introduction
of the original DF90. The second generation
DF70/80/90 follow in their predecessor’s footsteps
employing the same method to provide an efficient means
of supplying maximum propulsion.
The key to gaining maximum propulsion is through the use
of a large diameter propeller with a suitable pitch. But
spinning a larger propeller requires more torque, which
requires larger gears or a larger gearbox adding weig