Not mine, but came across it on the Craigslist. Looks all original. Just thought I'd alert you guys if anyone's looking for a collector bike. It's about half hour from me if anyone eyes on it. *if this isn't allowed or frowned upon, my apologies to the mods (hence why I didn't include a link due to being unsure)
FWIW, you can bore the 400 cases to the cylinder diamter of the 500 and put a 500 set of barrels on it. The cases are the same, just machined differently. Additionally, the 400 has better stock porting than the 500, so ideally, you want 500 cylinders with 400 porting. WOW....not a small number on that critter !!!!!!
I went with a 400 lump as the parts are way more plentiful - considering it will be a track only bike and not a collector. Dont give two sh*** about power, just reliability and fun so it was a no brainer.