Thanks for all the feedback -- I hope I can also share some experiances sometime.
My main "problem" is actually, that the bike/engine needs miles on it to be understood. I have my XLH since 1992 and by now I understood most of that specific bike. I had many different carburetors on it (the stock 900) -- a Bendix (came with it), the DC-11, the DC-6, CV, Mikuni VM, Dellorto 38 and 40 and the CV. From all carbs I loved the CV the most for the ease of use and good power (at least for my "butt" ) -- I liked the icredible "drama" on the Dellorto 40 in high rpms, and I almost went crazy in trying to set the DC-11.
When I drive on of my bikes or a car (whatever), I like to go fast and check the handling, but I am not crazy -- I have a family and kids and I am actually happy to live. On the track I like the "kick" of competition, but drifting on dirt without a front brake in between others is quite definately scary. Saying that, the bikes performance is propably way byond my willingness for risk. On the street, even a modern bike is somewhat dangerous and Germany is plastered with speed limits and the respective radar stations. So the realistic street operation is between 45 and 75 mph on (hopefully) curvy roads. On the track I would ride "vintage gold", hence with modified WLs, Ironheads, K-models, KRs -- even if I would be one of the better riders (which I am not), a 77cui XLR is propably overkill. Hence I rather make sure the bike works flawless and has a smooth power distribution -- adding a preferred riding position with reliebale brakes, frame and suspension and I have what I was looking for. I think I have a good basis for that.
Actually I would need to go on the street now for breaking in the engine -- how on earth did racers do that? Just having a few heat cycles and "on the track"? -- As riding on the street is very restrictive in Germany, I will use the next two months to add the stuff needed to be street legal. Eventually you will like my electric system, but its not ready yet
I still have the carbs mentioned above, so once I ride on the street, I will find out the correct carb diameter for a smooth power band and decent top end. I have read that the Tillotson has been bored out back in the late 60s? Maybe a 42mm Tillotson would be a good choice?
Lets see .. Cheers, Ralf