Back when I was a wheelie boy we used to go by exits on the parkway. I did close to 3 miles a few times then it gets boring. This was on a 4mill stock cylinder with my wheelie port job ,+4 timing,mull engineering pump gas head. Fmf fatties , stock carbs, rear brakes controlled off handle bars. I ran the idle higher than most and the clutch cable a Lil more slack than most to make slow wheelies a lot easier. Slow wheelies require a good feel for the clutch and the ability to operate it with one finger in unison with the rear brake