JP, I'd rent a bike to take to track. There are companies that do that.
As far as a sport bike, I'd get a used one where the owner might let you test ride. You can't test new bikes (at least I've never heard). They often have demo rides at bike shows or races, so I'd take advantage of a program like that. Or if you got good buddies with sport bikes, as them to let you try it.
You're a big dude so you'll need to think about comfort.
DRZ SM, fun factor. Not a freeway bike.
R6, GSXR600, ZX6, great everything, but perhaps not enuf power for guy like you.
749, 848, nice too look at, not enough power. Aggressive ergos but not bad.
748, 916, most beautiful bike ever. Awful to ride on civilian streets or highway. Stay away.
I've had a couple liter bikes, never liked any. But I'm half your size.
R6, GSXR600, best track bikes for me.
GSXR750, best all around bike I've ridden. Hard to find.
Stay on Jap bike. They're the only ones made for both track and civilians.
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