I dunno, I guess every once in a while I spin that motor up to see how she'll do. But I'm not that into riding hard like that. I'm kind of a 'grandpa' rider, I just enjoy sitting back and enjoying a comfortable ride. I have a lot more fun laying into corners and pulling out of them with V-Twin torque (the good corners you never go very fast anyway!) than I do opening it up with straight line speed.
I always thought if I had the need for speed, I'd just buy an old beat-up sportbike for a grand or so off of Craigslist. I find them all the time. An old 600cc Kawasaki or something, some teenage kid will buy it as his first bike, wreck it, then sell it on Craigslist for $1000. Plenty of them still run and ride fine, just cosmetic. But that way I could get a little speed and serious cornering done, and go back to my cruise for the rest. But; I really never have been that in to going fast. I rode my buddies ZX-10 and I never really opened it up, I rode it like my cruiser.
But that's me. If you're not afraid to let the motor spin, that 9 will really surprise you. Alot of folks who complain about it's performance, I think, are shifting around 4 or 5k RPM's like it's some big pushrod twin. That thing redlines near 80000 RPM's, let it get there! I do try to, once every month or so, get up to second gear and then peg it at the rev limiter, just to get a 'feel' for what the rev limiter sounds like, so that when I do open it up I shift right before it starts to bounce; where that motor likes to be.
For the record, the one time I ever 'raced' I went stoplight to stoplight with a friend on his 88" Harley Road King. I dunno how far it was, I hit 65mph before I hit the brakes. I was ahead of him until I braked, I suppose he technically 'won' since he braked later and harder, but we were just having fun. Point is, that 900cc V-Twin, when allowed to reach the top of it's powerband, beat a 1500cc Harley twin. Personally, I'm not a fan of racing bikes on the street and stuff. And again, that's not what I bought the bike for. BUT, I mean, everyones gotta open it up once right?