P.AP. Team RM80, User Manual

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Ros 125 Engine, Components and Elements.
STARTING THE ENGINE
It is forbidden to start the engine without the propeller and/or the reductor gear. A two-
stroke engine has very little mass and without the load of these elements, it reaches its
maximum revolutions in a fraction of a second. There is no RPM limiter. All mechanical
components are designed to stand only to those RPM limits of the propeller. Over revving
could be catastrophic for the engine.
Pulling the pull start rope should be precise in order to NOT to damage the start-up
mechanism (PICTURE 23). This engine includes a variable lead ignition and delays the
spark before reaching 200 RPM in order to make start-up easier.
Warming-up requires at least 1-2 minutes. During this period you should accelerate
progressively in order to reach the proper operating temperature. Avoid letting the engine
run at 4500 RPM, since at these revolutions, the clutch shoes are constantly opening and
closing due to the limited centrifugal force.
If you want a cold start, you only need to press your finger against the push-button valve
over the inner membrane of the carburettor and at the same time on the petrol circuit feeder
pump, injecting the amount a feeder pump can hold. We recommend full-throttle at the
same time you are pulling the starting rope. When the engine has started, you should leave
the engine ticking over as soon as possible.
If the engine is hot you do NOT need to use the feeder pump or the throttle.
Each situation requires a specific action depending on the state of the engine. If you ignore
this piece of advice, you will have difficulties to starting. By means of practising you will
sense the proper action to take. A good thing is to remember how long it has taken since
you last start it up, thus determining if the next start will be cold or hot.
REDUCTION GEAR AND TRANSMISSION
The reduction gear runs in an oil bath and is quite efficient and reliable, and has a very low
noise production. Its ratio is 3.65:1. Very little maintenance and adjustments are necessary,
except check every 100 hours that the oil level and state of the clutch are correct. The amount
of oil to apply is 16 ml of SAE 140. The transmission from the crankshaft to the reduction gear
is connected by means of a dry centrifugal clutch that allows the propeller to be stationary
when the engine is on idle. No maintenance is required apart from periodic inspection and
removal of friction material dust.
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USER MANUAL