Do all the basic maintenance. Fluid changes, filters, new plug, tire pressure,put a wrench on all the major nuts& bolts. The more things you touch the better chance you will prevent future problems. The first tank I would add 2oz. of Sea Foam conditioner, to try to clear the fuel system. You may need to adjust the idle mix screw to get a smoother idle, and a clean circuit is the only way you will be sure.