Am I too big for ninja 300?

I'm 6'3", and I was looking at buying a ninja 300r, Honda cbr300r (when it comes out), or a honda cbr500r? A lot of my heights is my legs, and I was just wondering if I would be too tall for a ninja 300.

Ref: http://cycle-ergo.com/

If you are "too big" for the Ninja 300 you will be too big for the CBR500, or nearly any "sport" bike as they are all built for people 5'6" - 5'9".

You can fit a Kawasaki KLX250SF, or even a big KLX650.

Yes and no.
As Dimo stated sports-bikes, pretty much all of them are not made for taller people, you'll fit but after about 20-30 minutes it will be like riding a pony wishing you had a horse. There are bigger ponies (more power) but they are only slightly bigger bike-wise.