A dual sport will let you do both. There are plenty of 250cc dualsports that are light enough to teach you proper off road technique, and still have enough power to get up to freeway speeds.
The 650s are very heavy by off roading standards, and probably not an ideal machine to lean dirt riding on.
Dual sports also have many of the characteristics that make sport bikes so much fun on the street. In fact, in tight twisty situations where high end horsepower isn’t usable, dual sports with good riders have been known to out-pace super-sports… Just more proof that it is all about the rider and not the ride. As an aside, look at the rise in popularity of Motards…
Riding off road teaches you a lot of things you can’t safely learn on the road (like how to slide your front wheel). Everyone I speak to says the best way to learn is on dirt. And, having done my ERC, I think off roading would be a helluvalot of fun.
I (having started on the street) have no issues with people starting on the street instead of dirt. But I think if you have the facilities near by, and the riding buddies to go with (and to show you the ropes) getting a bike capable of dirt riding will be well worth your effort. You won’t regret it. And as I said, a dirt capable machine is still capable of plenty of fun on the street.
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