I would like some more oomph at the top end. I've been riding the V-Strom 1000cc the past couple of days, and I can confidently pull off passes with it that would be risky with the Burgman. The 650 simply runs out of steam in the mid 90 mph range. The V-Strom accelerates very strongly right up to 135 mph, where it is electronically shut down.
I wouldn't mind if the Burgman was electronically limited to 110 or 115 mph, but I would like it to pull strongly right up to that point.
This is an issue here in the midwest, where you have high speed 2 lanes - and cattle trucks that like to run at 65 - 70 mph on these roads. Following a cattle truck is, at best, a stinky experience. And I don't like following trucks in general, because they obstruct my view. Add a car or two following the big truck, or two trucks in a row, and you've got to have more top end performance than the 650 has, to comfortably pass before the next hill or curve.
I honestly think that Suzuki could get that kind of performance out of the existing 650 engine. It is not in a very aggressive state of tune. It's quick in the low & mid range, due to the cvt and decent torque, but it dies out badly before 100 mph due to limited high rpm horsepower. As you add bigger windscreens (more wind drag), and carry more weight, it gets worse.