In the '60s, Harley Davidson-began development of the KRTT roadracer based on a 750cc flathead V-twin. By '70 it could go 150 mph. It, and the other bikes of the day, had their seats, tanks, pegs and controls positioned for the straight-up, knees-to-tank riding style of that era. With relatively minor reconfigurations of those components, those bikes would feel as comfortable and as ride-able as anything built today. Bikes from any era can be adjusted to suit all riding styles. But leathers from that period would create serious restrictions to hanging off.