So glad you found this as I get sneered at on all lists repeating what Brian Slark told us a few years ago at the Texas Lake of The Pines, ie: that the Evo engine is basically a Norton chamber/valve head design on top and in the rubber but also *helms joint radius rod linked* engine mounting. Mostly Hopper's design we were told & now got the rest of the story. So don't blame the messenger when I keep repeating Harley's are the closest kissing cousins to Norton heavy twins. Erks some the Harley burly's I inform of this too, sheeze. Best rub of all is letting the BMW'rs know where their iconic 'German' engine got its name. Remember TC's HogSlayer competetion with close by HD's race department - well nothing like a family feud eh.