The carb is only a 3/8" bore carb. The engine will do a lot better with a larger one not to exceed 1/2" The Zenoah 23 carb is readily available but they cost around $40 (Walbro WA167A) . However, your original carb is usable. Disconnect the throttle arm spring but don't take it off. Most people remove the choke.



If you have a fixed advance type electronic ignition, the Timing should be set at 28 degrees. You will need a protractor fastened to the crankshaf. an old plug with a dowell glued in the center to act as a piston stop. And a piece of wire and a paper clamp to fasten the wire to the fins to act as a pointer.

Someone more familiar with your ignition design may know if it is the fixed, advancing, or the type that retards when the engine is turned slowly but advances back to the 28 degree point as the engine gets back up to speed?

For the fixed type, Install the piston stop plug. Bring the piston up to the stop and take note of the the degrees on the protractor. Move the crank in the other direction to where it stops without moving your pointer. Take note of the degrees. Top Dead Center is at a point half way between (beyond) the upper limits of what the piston traveled. Remove the piston stop and place the crank at top dead center.

Then you want to get your spark to trigger at 28 degrees before top dead center.

Enjoy.

Jim