After seeing Sky's XS650, it makes me want to grab another engine and turbocharge the hell out of it, then throw it into the hardtail....NOW THAT WOULD BE SWEET!!!!
His bike is sick....turbocharged, fuel injected, and running Microsquirt! The only hard thing to do would be to find better pistons and rods. Or maybe a head spacer would work, idk. I have an extra running KZ400 motor that I thought about boring out and building just for the hell of it!