Gents, As most would know, primary and transmission on a sportster are lubricated with the same sump, same oil. Lubricant used must suit the clutch, primary chain, and gearbox. HD service manual says to use Formula+. I've done a search without getting information specific. What oil are you guys using in your ~2008 sporty transmissions, and why? I've just changed and put Spectro STL in and it seems noisy/clunky now. Maybe I've just gotten more sensitive because I changed it.