Nirvana TOP 80, Assembly And Maintenance Manual

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last update 23.10.2012
CARBURATION
CARBURETTOR
The motor carburettor is adjusted for best performance at the factory in Italy,
however due to thenumerous variations associated with different
geographical locations is would be prudent for the engine to be tuned at its
final destination or main flying location. Please ensure that this operation is
done by the distributor from whom you have purchased the product.
Alternatively it is possible (but not preferable) for a qualified mechanic who is
experienced with 2 stroke motors. It should be noted that this situation is not
preferable as most 2 stroke experienced persons/mechanics are not
experienced in high HP, high performance 2 stroke engines, and through
ignorance may cause more problems that cure.
Engine “RICH MIXTURE” will cause excessive fuel consumption and engine
vibration.
Engine “LEAN MIXTURE” will cause the motor to run hotter than normal, and
may under severe conditions cause, the piston to seize in the bore. Lean
carburettor mixtures have also been associated with: Holing of the piston and
“softening” of the pistons crown which leads to its collapse due to the
extreme heat generated by the lean mixture.
Run the engine for about 10 min. at 75% + power, this will cause the spark
plug to be coated in fuel combustion gas deposits. This is the Ultimate way to
verify the correct fuel mixture ratio. The correct acceptable colour of which
is, anywhere from light coffee colour to dark a chocolate colour.
The spark plug
colour range is:
Grey Tan / Clean Dark Brown /
Black
Therefore
carburettor
screws is:
Lean (lean,
insufficient fuel)
screwed IN to
far
Correct Rich (too much
fuel) screwed
OUT to far