Apparently he has some kind of dual-clutch drivetrain that allows him to use the separate recoil starters on both engines...I wish I had a photo of the other side...
I'm so jaded from seeing custom bikes that don't work well (or at all), that when I see something like this, my first question is always "How does it work?", and I hate it when the builder tap dances around for twenty minutes before he finally admits "Well...it doesn't, actually".
That usually sucks all the 'cool' right out of it...