It's more about cylinders than displacement. The 600cc bikes tend to be inline fours. Four-cylinder bikes have touchy throttles. I started on a 650cc V-twin, and it wasn't "too much bike". Bike series like the GSX series, CBR series, ZX-6R, and R6 are generally not considered good beginner bikes. They're made to go very fast.
I'd get a bike with exactly two cylinders. They run a lot smoother than a single-cylinder (thumper) and have plenty of torque and HP.
Take the course, then buy your bike. They provided bikes for our course; I'm assuming they will for yours, as well. You'll have to sit on a few bikes to find out what's comfortable for you.
Dude, quit listening to the people on here. Get what you can learn to ride. Ask the course director to help you when you're done. These people'll try to put you on a 250cc. at 6'1 you'd look like retarded on a 250cc on the road.
And here is the answer you dont want to hear! NO! Any of the 600cc race class bikes, the cbr600, r6, gsxr600, and zx6r are for experienced riders. The 600cc vtwins are great beginner sport bikes, because they have half the power of the I4's. Look for the ninja 650r or the suzuki sv650. Ride them for a year or so and then upgrade. Use your head, not your ego when buying a bike and you should keep from being a statistic.
No. They are a death trap for a beginer. Seriously, there is no nice way to say it. Take a look at the Suzuki s40 Boulivard. It is 652cc. Single cylinder. Has great low to mid power. Just what a beginer needs. The 600cc class has touchy throtles and trickly clutches. Made for raceing. If you tell the dealer you are a beginer they should be shot for recomending a sportbike.
No. They are a death trap for a beginer. Seriously, there is no nice way to say it. Take a look at the Suzuki s40 Boulivard. It is 652cc. Single cylinder. Has great low to mid power. Just what a beginer needs. The 600cc class has touchy throtles and trickly clutches. Made for raceing. If you tell the dealer you are a beginer they should be shot for recomending a sportbike.