Radne Motor Raket 95, Owner'S Manual

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Raket 95 Manual - English
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Raket 95 Manual - English
6. Technical data for Raket 95
Engine model One-cylinder two-stroke engine of Dual Charge model
Cylinder volume 94 cm3
Cylinder diameter 56 mm
Stroke 38 mm
Connecting rod length 74 mm
Carburettor Tillotson HS 319 a, venturi 17,7 mm
Ignition system Selettra analog
Flywheel Selettra 113,9 mm
Starter system Electric, integrated starter (or Magnapull cord starter)
Starter battery Raket, 14.4 V Nickel-metal hydride (NiMH) 3.0 Ah
Spark plug NGK BPM 8 Y
Clutch Centrifugal clutch metal
Sprocket on clutch drum 11 teeth, type 219
Exhaust system Tuned system with end silencer
Fuel Alkylate or 95/98 octane lead free petrol
Petrol mix 4% of synthetic two-stroke oil
Squisch Min 0,8 mm
Combustion chamber volume Min.11,0 ml
Bearings Original SKF 6203 TN9C3
Sealing rings 17x28x7 sealing lip with Teflon coating and dust seal
Idling speed 2500 rpm
Max rpm 12500 rpm
Max power 7,6 kW at 8600 rpm
Recyclable parts in the engine 82 %
Emission values CO and HC According to EPA2 standards
Weight 12.1 kg complete engine (engine, starter battery and
silencer)
7. What do we mean by an
engine of Dual Charge mod-
el?
If one looks at the inlet in the cylinder
one can immediately see the big differ-
ence. The inlet is divided up into an upper
section and a lower section. If one then
follows the channels one will see that the
upper channels go directly into the cylin-
der’s upper section, while the lower sec-
tion of the inlet leads via channels down
into the crankcase, just like an ordinary
two-stroke engine.
Insulating flange with two channels en -
sures that the two streams of air are not
mixed together. As you can see from the
picture of the cylinder, the two air streams
continue each of them through their re-
spective channel into the cylinder.
You may wonder why the air that travels
on the top side of the throttle doesn’t
suddenly stop when it no longer has any
depression to pull it. Well, when it comes
to air it happens to be the case that when
one part of an air mass moves, it pulls the
surrounding air along with it.
When it comes to the operating strokes,
when the piston moves downwards
into the cylinder, a port is opened in the
cylinder at which point the air stream that
is not mixed with the fuel streams in and
rinses clean on the top side of the piston.
The result is that when the mixture of
fuel and air flows up from the crankcase
via the transfer channels it meets with a
clean combustion chamber. Because of
this the combustion is much purer, which
in turn means purer exhaust fumes. Raket
95 has such good values concerning
the content levels of carbon monoxide,
carbon dioxide and hydrogen carbonates
(HC) that it is able to meet the required
emission demands without the use of
catalytic exhaust emission control.
When the piston moves upwards in the
cylinder, in other words during the inlet
and compression stroke, a depression
occurs in the crankcase. It is this depres-
sion that enables the engine to suck in
air through the carburettor. The throttle in
the carburettor divides up the inlet air into
one part beneath the throttle and one part
above it. It is only the air that travels be-
neath the throttle that then sucks up fuel
through the carburettor jet. A rubber inlet
flange sits between the carburettor and
the cylinder. The inlet flange also has a
plate that divides the air and fuel mixture
when the throttle is completely open.
However this is not the only advantage
with Dual Charge. The purer combustion
also means that the fuel consumption
is reduced and that the exhaust fumes
do not smell as bad as in the case of an
ordinary two-stroke engine. Dual Charge
engines are also much cleaner in the
crankcase which has been shown to have
a positive effect on bearings and seals.