There's some weird stuff going on there. The 'background image' is not, in fact, a background image but rather a foreground image in a div that has a fixed position at the bottom of the viewport.
If you want to make it a background image and center it in the page body, I think you would have to do something like this:
background: url('images/homebg.png') no-repeat center center #FFFFFF;
And you'd have to get rid of that div that is using the image as a foreground image:
<div align="center" class="bg-image">
<img src="http://www.jobsincycling.com/wp-content/themes/CricketJobs/images/homebg.png" class="img-small">