Unless you are over 6'3" tall or are extremely overweight (meaning well over 300lbs), even the smallest 250cc motorcycle will be able to accommodate you without difficultly. To provide an example, the Ninja 250R has a load limit of 348 pounds. That is more than sufficient to accommodate a heavier rider in full gear and still leave plenty of space for cargo in tank, tail and saddle bags. Or enough to allow two-up riding between two average weight individuals.
The idea that bigger riders need bigger bikes is almost laughable. It's like saying small drivers need Honda Civics but bigger drivers only 100 pounds heavier need to drive Hummers to get around. Or Corvettes with plenty of power to pull their ample frames, as the analogy goes. It is only because of the small physical size of bikes compared to their users that this train of thought even exists. It simply doesn't hold up to scrutiny. A look at any motorcycle owner's manual will confirm that for you.
My first motorcycle was my B12. I've felt comfortable on atvs, 3 wheelers, and such since I was a little kid working on a farm. I think mental maturity is the most important factor, when considering weather or not one can handle a larger bike or not, and those of us who grew up on these sort of vehicles may take to motorcycles faster.
I take issue with the argument that larger people (weight-wise) don't need bigger bikes. I agree with the author that height is more of a consideration than weight, and being 6'8" and 300lbs, I suffer from both extremes. I feel this makes me a good judge in this case.
I have ridden a Ninja 250R as the author mentioned above, and I have bottem the darn thing out on reletively good roads. So I disagree with his statement.
What the author fails to point out is that usually larger bikes have beefier stock suspension and tends to compensate for heavier riders. He also hasn't made the connection between frames seat height and engine size. Unfortunately, the two seem to go hand in hand. Usually, the larger the CC's the larger the frame and/or seat height.
Also, IMHO, larger riders can get away with man handling a larger motorcycle once in a while, should a potential tip over occur.
It is too bad, that the American market doesnt support more street bikes in the 250CC - 600CC range. The japanese market is strong in this area, but the number of American bikes in this engine size seems to be shrinking.
Oh ya, for the record, I don't fit well in Honda civics, but I would drive one if I could get my legs around the steering wheel, man they get good milage! I also wish I still had my honda helix! Man, that was a ride!
jesse