ooooooh..a 4-stroke..see i really dont know anything about hondas..ok well those tuned pipe designers will be useless for you if you have a 4-stroke. I dont know all that much about 4-stroke exhaust, but in general, the more flow, the better. i dont know what kindof exhaust you have, but from the pictures i just looked at of the ss50 in the photo section of this site, it doesnt look like you'll be able to do much (unless you wanna get much louder). The pictures show exhaust pipes which seem to be pretty much straigt pipes with a muffler at the end. if you didnt mind the sound, i might try doing some sort of a horn design (going from whatever the original pipe diameter is to 3 or 4 inches in a horn shape).