[Zhack]

I just did the airbox, exhaust and timing mods for my CRF70. How do I richen the mixture. I see there is no throttle slide so I assume there is no needle. All else I can see is the idel adjustment and what looks like a fuel screw or air screw next to the idle. What is that? Is there a main jet somewhere in there as well? How should I adjust fuel mixture to make up for the increased airflow?