In my case I have had some different ways of fuck white and blacks. I had only one black boyfriend and other of my boyfriends was crossed-breed between black, caucasian and south aboriginal. With both of them I used to fuck a lot of times by behind as many in doggy style (four legs) as being standing placing my bent body over chair, table or facing a wall or door. In bed I used to fuck with them in missionary position with my legs wrapped around their bodies and my feet crossed. In the case of white guys, I don't know why but I don't use as often as blacks behind positions. With my white husband I usually fuck in missionary position with my legs open, despite he asked me a lot of time if I could wrap them...but when I wrap my legs around his body, is only to pleased him because I feel more pleasure with my hubby keeping my legs open. In both cases (white or black) when we fucked in missionary position and I wrapped my legs around their bodies, all of them cummed immediately.
With black guys I often felt the necessity to be fucked by behind...I don't know why, so if anyone of you could give an explanation, it will be well accepted.