These friends of mine (brothers who are total early Sportster and K-Model crazy addicted) have a 1957 XL. They (one of them) blew this thing up years ago. The motor started knockin' and grinding, and he just kept going. All the way home. The motor sat for years and years. The rod rollers looked like square, woodruff keys. I don't know what they ran for oil in this, but I hope the company doesn't make it anymore.
Damn. What a mess.