Like blacknblue said, if it's stock (meaning stock pipes) then you're fine, it will be fairly mild-mannered.
If it has pipes, I don't think it will be TOO much, but you do need to take precautions. There is a huge difference in the power delivery between a 2-stroke and a 4-stroke (and snowmobiles do NOT count. Their transmission creates a completely different kind of power delivery).
You definitely need to take it easy, in some mild open terrain your first few rides to get used to the power delivery. Seriously. When you grab a friend, make it clear this ride will be very boring for him, because your entire goal is to basically ride around in circles getting used to the power delivery. This ride will NOT be challenging, it will NOT be interesting, it will NOT include any new sights or exciting terrain.
And don't be surprised if you get excited, even aroused, and never want to ride a 4-stroke again.
Duncan Racing 340PV, +2 A-arms, +4 LSR axle, and a host of other goodies.