Post Master General
Join Date: Apr 2012
Location: Bowling Green, VA
I Ride: '09 ZX6R
I'd wait on the dampener until you are familiar with the bike. As long as you don't adjust the fork angle, the rake and trail is IMHO sufficient for street use without a dampener.
As far as getting comfortable with the bike: the biggest difference you will notice compared to your 300 cc bike, is the mass of the 600. It's got bigger brakes because it's a heavier bike.
If you keep the acceleration down, until you are comfortable with the low speed handling you should have no issues with the 600. Suspension is better, power is better, ergos are probably not that much different.... stay out of the speed, and get used to the weight. It won't change direction as easily, and it will take longer to stop from the same speed. More grunt down low, and one heck of a lot more on tap on top.
I'd expect you will feel very comfortable within a day or two. Take a few weeks, get through the break in, and then expand your envelope.
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