New here and already picked up some valuable pointers! Was wondering what 4 to 1 pipe I picked up for the bike about 20 years ago when I pieced it together. It was old and used then. Thinking perhaps someone might know. Its very light and one piece. The bike runs like a bandit (faster than I would have thought an old 750 aught to be at least) even though Ive never bothered to jet it or even check them-kinda funny since Im a mechanic of 39 years,lol! Aint broke dont fix it. TIA Bob