I am looking to make a foray into the world of semi serious digital camera photography.

I guess i need to explain my needs and what to use the camera for, so here goes

I am an avid Motorbike rider and I enjoy travelling to motorbike racing around the uk.
Therefore I require a camera that will take great pictures of what may well be a very fast moving object.
This object more than likely will be the otherside of a chain link fence, so I will need to be able to zoom past this.
I have a compact camera at the moment and it does take some decent pics, but i find that i am having to guess where the bike will be when i press the button and allow a certain amount of lag. I do not want to do this with my new one, i would like to point and shoot preferably without having to calculate a delay into the photo.
I am looking to spend a rough price of 700 for the body and say an 18-55 standard lens, I can then buy other lenses to suit various aspects.
I do not have a camera model preference but would like the best i can afford to do what i would like it to