1. Once you have started the engine let it run at idle (low RPM) for at least 125cc of fuel, the idle must be regular, and if the RPM goes down and the engine stalls, you must close the idle needle (1/4 turn at a time), and if the RPM goes up, you must open the idle needle.
2. After the engine has run at idle for 125cc, you should let the engine cool down before restarting it (be certain that the piston is not stopped at TDC), and open the main needle for at least ½ turn more than it was originally set. We now suggest you run the engine on the track so it will be cooled properly. During this process, be sure the engine does not make too much RPM (the engine must be making a sound like a four-stroke engine and you must see fuel coming out of the pipe). If the engine makes too much RPM, close the throttle immediately and open the main needle one more turn, and repeat if necessary until the engine suffocates due to too much fuel, and in this way you will be sure there is enough lubrication and the RPM does not go too high. Run the engine like this for at least 375cc of fuel, and avoid extended periods of full throttle running.
3. After this you can start closing the main needle so the engine makes more RPM but still makes a four-stroke sound and smokes a lot, this for at least another 375cc of fuel, and avoid extended periods of full throttle running.
4. After this you can close the main needle further until you reach about 80% of the engines performance (more RPM but still smoking), this for 250cc of fuel.
5. After this you can really tune the engine to go to 90% or 95% of its power but take care so that you do not overheat the engine causing it to loose power, if this happens stop immediately and open the main needle 1/4 of a turn.