I know the 350x's super scoops and front fender actually were designed to act as an air scoop and direct air through the oil cooler and over the jug fins to aid in engine cooling. Super scoops may be an option for you if you choose that route. As for side pipes, the only things I have seen are frame out drag pipes on 2 strokes. You could sure make one for your trike if you wanted. For low profile tires you would want 10" or bigger rim diameter and run 18" or 20" tires.
85 Kawasaki KLT 160
85 Kawasaki KLT 110
82 ATC 70
2000 Scrambler 500