Originally Posted by littletinman
I then tuned my carb by moving the needle from the mid position to second from the top. I gained 5-7 mph to my top speed (i was only getting 20, with a 66cc, and 41t). Most of my four stroking problem is gone and I have a lot of power. Going to move it to the top position next and see if that helps anymore.
Remember, the slide needle has very little to no effect on throttle positions greater than 3/4 open throttle.
If you are still experiencing a rich condition beyond 3/4 open throttle, a re-jet is in order.