User manual

58
b) Setting the Idle Mixture Adjustment Screw (L)
• Putthemotortooperatingtemperaturebyrunningthevehicleforoneortwominutes.
• Ifthemotordoesnotacceptthrottlewell,theidlingmixtureistoolean.Turntheidlemixadjustingscrewanticlock-
wise (towards the left) to make the mix richer.
Adjust the setting gradually by about 1/8 turns of the idle mix adjusting screw anti-clockwise.
• Ifthemotoronlyacceptsthrottlestutteringandunderstrongdevelopmentofsmoke,themixtureistoorich.Twisting
clockwise (to the right) makes the mixture leaner (the fuel share is reduced).
Adjust the setting gradually by about 1/8 turns of the idle mix adjusting screw clockwise.
c) Setting the Main Nozzle Needle (H)
• Lifttheactuatedrearaxlefromthebottomanddrivetheengineatoperatingstatetemperatureatfullthrottlefora
short time.
• Thefullthrottlemixtureatthemainnozzleneedlecannowbesetinstepsof1/8turneach.
Turn the main nozzle needle clockwise to the right if the mix should be leaner.
Turn the main nozzle needle counter-clockwise to the left to make the mix richer (to increase the proportion of
fuel).
• Foralongmotorservicelife,preferaslightlyrichcarburettorsettingtosetthemainnozzleneedle.
 Forthis,twistthemainnozzleneedle(H)slowlyinsmallstepssothattheenginereachesitsmaximumspeedbriey
after the control signal „full throttle“ and runs smoothly without stuttering.
Then turn the main nozzle needle counter-clockwise to the left by about 1/8 turn to increase the fuel share (= rich
carburettor setting).
• Aftereachmotorrun(tanklling),allowforasufcientcoolingstage(approx.5-10minutes).
Attention!
It is always extremely important not to make the mix too lean! Observe that the engine is lubricated by the
oil in the fuel in this two-stroke engine.
Too little oil in the mix (= lean carburettor settings) will cause the engine to overheat and the piston to seize
due to defective lubrication. During operation, a slight white smoke vane should be visible from the exhaust
atalltimes.Ifnot,stoptheengineatonceandenrichthemix.Alsomakesurethatsufcientaircirculates
around the cylinder head in order to avoid overheating. The best engine operating temperature is approx.
100 - 120 °C. Check the temperature with an infrared thermometer.
You can tell that the engine is run in when it can be cranked up in cold state without spark plug and without
noticeable resistance. Only now must the engine be operated at full output.