8. Driving
a) General Information
Enrich the mix by adjusting the main nozzle needle again, but keep the setting as lean as possible so that the model runs optimally.
Attention!
It is always extremely important not to make the mix too lean! Keep in mind that the engine lubrication of the two-stroke engine is effected via the
oil contained in the fuel. Too little oil in the air/fuel mix causes engine overheating and piston seizure because of faulty lubrication.
During operation, a light white trail of smoke coming out of the exhaust pipe should always be visible. If not, stop the engine immediately and enrich the mix.
Also make sure that sufficient air circulates around the cylinder head in order to avoid overheating. If necessary, create a corresponding opening in
the car body.
The best engine operating temperature is approx. 100 – 120°. Check the temperature with a drop of water on the cooling head: If the water evaporates abruptly,
the engine is too hot. At operating temperature, the water evaporates in 3 – 4 seconds.
Make sure that the rechargeable batteries of transmitter and receiver are fully charged.
Check the range of the remote control transmitter and the function of the RC system.
Always drive with the car body attached. Thus, you protect yourself from burns if you touch the engine or the manifold by accident and you protect
the components from damage by whirled-up stones.
Get used to the driving behaviour in curves. Practice steering when the model runs towards you!
b) Effect of Manner of Driving on Individual Components
Engine
The model's FORCE combustion engine is air cooled. This means that the air stream has to cool down the engine (air cooling).
This is why you should try to avoid accelerating the vehicle with frequent, strong load changes (short throttle bursts from low rev range and jerkily lowering the
revs). The brief high revs strongly heat up the engine without there being appropriate cooling by wind, as would be the case at a drive with constantly high
revolutions (high speed).
As a result of overheating the engine, the piston may get stuck in the cylinder liner (piston gets stuck) and suddenly block the drive. This could cause consequen-
tial damage to the entire drive section.
Drive in part-load operational range with revs that correspond to the desired speed.
However:
In case of continuous slow driving, wind cooling of the engine is still guaranteed, but there may be damage on the clutch (wear, overheating through
slipping clutch).
Clutch
The clutch will not engage at idle speed. The model keeps standing still with the engine running.
In case of slowly increased rotation speed, the clutch 'slips'. The vehicle starts and drives slowly. Just as with a 'real' car, constant slipping of the clutch can
cause the clutch lining to „smoke away" or „burn off".
The clutch first engages with high engine rotation speeds. The engine rotation speed is transmitted to the drive strand without slipping. Wear of the clutch linings
is now at its lowest.
Frequent, strong load changes by brief short throttle bursts and jerky lowering of the revs also reduce the life of the clutch linings. With short throttle
bursts as well as by letting the clutch slip, you will get slow speeds, but at the expense of the clutch.
Bearing
Overheating the engine and/or the clutch also has an effect on the clutch bell bearings. Leaking and resinification of the bearing grease (bearing runs dry) as well
as different expansion of the balls and the ball bearing case in the case of excessive heat can lead to a jamming of the balls. If the balls can no longer move
freely, there is frictional loss and therefore an additional heating up of the engine shaft.
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