Just bought an Eric Gorr 144cc 58mm 2006 YZ125 OEM cylinder and head from someone that had it 'sitting on the shelf'. It didn't come with setup instructions. What is a good piston to run and why? Anyone make a good twin ring? Are all YZ144 pistons that I'd want to run, flat topped? Cast or forged? Leaning toward cast for lightest weight and quicker revving. What is a good squish number? I'll be running at sea level, so some recommended jetting would be much appreciated. Is the timing adjustable on these, like a YZ250? If so, zero advance? I assume these kits come with setup instructions, and I emailed Eric to ask, but he hasn't got back to me for a couple of days.