Well that depends.... my first instinct is to say, of course you can still have a good orgasm! Your clit isn't buried deep in your vagina, and even your g-spot (theoretically) is only an inch or so in. So that shouldn't be an issue. It really is more of a technique thing than a size thing.

How did you acheive orgasm with your last partner?

"It's not the size, it's the style" - sure, it could be true. If you find it difficult to achieve satisfaction, try different positions.