Just curious if I have any bolt-in options or if it's a hack and fab situation with my XS400 frame? I've been thinking about a single thumper 500 engine. I'm thinking from a XT as then it shouldn't have a starter on it and just the kick start option. Aftermarket is pretty big and the lump in my XS400 is a shot in the dark if it's good or not. I got a loose as it was froze when I got it and still needs carbs. I figure for the price I can get a 500 for a 38mm Mikuni round slide for it'd be fairly close to how much I'd spend on getting some carbs and then if it dud in the end. What the hell, if it doesn't fit. I've got my MIG, TIG, compressor and ample air cutting tools, so where there's power to plug my tools in, there's a way it's going in. Just curious as what experience people have had with these 500 singles? Only thing I've seen with the older singles is to run another oil line to the rocker cover on the exhaust side to aid with lubrication but then it was solved in later models.