I'm curious how many miles you've put on that CB450? It sounds like you might be fairly new to street riding. No offense, but a CB450 is almost in the scooter-class, compared to a Busa. Having dirt bike time is a plus though. And it sounds like you have a good head on your shoulders.
A Busa is only going to go as fast as you allow it, but it accelerates so quickly and smoothly, you'll be very, very surprised. Be prepared to be initially scared, even at moderate acceleration levels. Realize you're entering a world nothing like you're used to. Twist the grip on a Busa, (like you do on your CB450), and your speed-o will be in the triple digit range - in a few short seconds. Speed is there in a blink of an eye and your reaction time (and good judgement) had better be keeping up! The potential for a novice rider to get hurt or killed on a Busa is certainly there. Insurance companies are well aware of this.
Where you might have had several seconds of reaction time on your CB450, the Busa's quick acceleration might only leave you a split second to react. Or you may look down at the speed-o and realize you're entering a corner at 90 (Whoa! You thought you were only doing 50!). Will you be ready to lean the Busa over at a 40+ degree angle and drag a knee through the turn? Is your skill level ready for these situations? It better be!
Two suggestions:
1. If you do decide to buy a Busa, pace your learning curve very, very slowly. It's unfortunate fact that unskilled riders have a tendency to get hurt or eliminate themselves.
2. A better (and safer) bet might be to pick up a 750 first and put a year or two on that.
Either way, best of luck!
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