What kind of carb is on there. I thought they had some kind of sha on there. There is only an idle mix, but a few different slides that can be used for better mid range. The air/fuel mix is going to come from the ret and then the air flow through your filter. You can restrict or de restrict the airflow in your airbox. And those carbs have a big difference between idle and WOT. Idle will always be too rich if you have the top end jetted correctly. Always get a few plug chops in around the block before taking it out on a longer ride. Grab a 4 pk of plugs as you will want a new plug for each chop.