ok, the screw on the side of the carb is for idle adjustment only, not for adjusting the mixture.
When you put the slide in the carb, did you line up the slot on the slide with the pin that's in the carb where it slides in? if that slot is not aligned with the pin, the throttle will be wide open and you will not have any control of it. the slot that i'm referring to is the slot where the throttle cable is held into the slide. there is a slot on the opposite side of the slide, but it isn't long enough for the slide to go all the way down into the carb. when the right slot is lined up with the pin, the slide will drop all the way down into the carb body. the pin inside the carb will be about 1/2 way down in the carb on the right side (when sitting on the bike looking down at the carb).Usually a cold motor will not start or it will have a hard time starting when the throttle is wide open.
If the slide is wide open and you have been trying to start it, your spark plug may be fouled. Pull the plug out and see if it's wet. If it is, dry it off and re-install it then try to start it.
I would check the carb slide tho because it's fairly common that people install it wrong and they don't line the correct slot up with the pin.
