OP,
I was fortunate enough to start riding when I was around 11 years old. The first 2 wheelers I rode had less than 10 HP, and topped out at around 40 MPH. Still plenty fast to have a potentially leathal interaction with a fixed object. 25 MPH is how fast you hit the ground, if you jump out of a second story window, as a point of reference. I have known a number of people in the past 50+ years that have died. Some of them have even been involved in motorcycle accidents. The H-U-G-E majority of the people I know who are no longer in this world, did something stupid that helped cause the end of their time here.
The human body was developed to protect the operator from typical accidents that occur when you cannot get going any faster than you can run. Even that, still leaves scars.
As you ride, you will push the environment, until you exceed your ability to control it. Whether that 'edge' is catastrophically bad or not depends on a multitude of factors. Good gear will somewhat reduce the probability of a fatal encounter, and it will significantly reduce the amount of injuries any given accident is likely to impose on the operator.
Slower, smaller, lighter bikes are good for learning how to deal with the inevitable. They give the operator more time to respond becfore the penultimate moment. If you have more time to decide there is a problem, and can take corrective action BEFORE you HAVE TO, the odds of sucess increase.
Chuck Yeager said that "A pilot crashes, when he runs out of air speed, altitude and ideas, all at the same time."
We fly, very very close to the ground......
Street bikes in general accelerate the rate at which decisions need to be made to survive. High power, light weight, and testosterone will lead to a lot more riders seeking the edge of control -- and that involves a much higher rate of decisions that must be made accurately, and well.
A newbie, without formal training? Starting out in the city? A lightweight, moderately powerful bike is a better choice than a 600. Personally, I think a DRz400, or a 300cc sporty bike makes a LOT more sense. 20 HP, sub 300 lbs? Greater than 70 MPG, topping out around 100 MPH isn't shabby at all.
Obviously, there's a lot of people here and elsewhere that started out with a 600 I4. And feel like they are sucessful.
Neither route is better.
Everyone who rides will eventually crash. Gravity NEVER lets up. Sooner or later your attention will not meet the requriements of the situation, and a 'gravitational moment' will occur.
The more experience and training you have, surrounded by the best safety gear you can afford, no drugs/alcohol, plenty of sleep, no anger issues, never in a rush, never distracted by a thong, or a sunburn..... the longer you will ride without incident.
