Hi Guy's


Today, I wanted to break in my brandnew YS63 S.
Starting the engine went well, but then the problems begun.
After 2 mins, I advanced the throttle, and the engine started to make a barking sound. When I opened up the needle from 2 1/2 to nearly 4 turns, the sound went away. Till some minutes at 75%, the rpm started to reduce, and all of a sudden, the engine stopped.

Restarting the engine was no problem, but the carb started to spit out a lot of fuel inside the Oxalys cowling... When closing the needle (high speed of course !) again in the directing of YS' recommendations (2 1/2 from close), the same sound reappeared....[:@]

Is there anyone who experienced the same situation, or is there someone who can help me out?


Grtz from raining Belgium,

Eric

You mean "woof, woof" like a dog?!?! I know there may be a language problem here, but that sound just doesn't make sense coming from a motor. Do you mean a back-fire, or maybe a sputtering sound, or something like that?

David

As I thought, the sound is difficult to describe...
The closest of your sound replica's could be the back firing sound.
Any solutions for this?


Eric

From what you describe, it sounds too lean at 2 1/2 turns. The barking sound is most likely the engine going lean and causing pre-ignition. This can also cause the engine to backfire. Both of these conditions could be the barking sound, both are caused by the engine being too lean and both can cause damage to the engine. The gradual slowing down at 4 turns sounds like the engine is too rich and is slowly loading up with too much fuel. Have you tried running it at about 3 turns or so? After you make a change to the high speed needle, run the engine up to full throttle for several seconds to see how the change affects the engine. Always make the changes in small increments, maybe 1/8 of a turn at a time until you get close, then just a click or two at time.
Paul