I'm an avid motorcyclist and autocrosser. I co-drove a friend's C-Sports Racer with a Hayabusa drive line a couple of years ago and decided that I wanted to build a BEC as a retirement project.
http://www.usa7s.net/vb/attachment.php?attachmentid=13523&stc=1
With that in mind, I started looking online at what was out there. Last year a completed MNR Vortx RT with a Yamaha R1 showed up on eBay, local to me, for a reasonable price. As much as I wanted to have the satisfaction of building one, I couldn't resist.
http://www.usa7s.net/vb/attachment.php?attachmentid=13524&stc=1
It is very well put together, and so far I have only made minor adjustments/repairs/updates.