I don't know why everyone gets so hung up on CCs. I rode 650cc twins for many years and was perfectly happy with them. I bumped the compression up to 10.5:1 and just tuned it and rode. I now have a 790cc twin that I am happy with and building an 865cc chopper I am sure I will also be happy with. I have crossed multiple states loaded down with gear no problem. North east PA to Yellowstone park in 36hrs on a 1966 TR6C for one trip.
I learned all I need to know about life by killing smart people and eating their brains. Eat right ,Exercise ,Stay fit, Die Anyway!