Cams
For the record, I changed the original Shadow cams (1951 - Mark II?) for Gary Robinson 105's. I think these are the same profile as Mark II, with slightly different overlap timing. CR is 7.3. (Interestingly, so long as valves don't clout pistons, Manx Norton valve timing isn't apparently particularly critical. Within about 5 degrees is OK. But ignition timing HAS to be 34 degrees with a mag, or the ****** won't go.)
The Vin tends to "lie down" a bit over 90 (which I think means it needs more ignition advance than 34 degrees), but I rarely go above 90 anyway, and up to that it is "adequately fast". It won't match 'iggins 1200 Shabby Shadow though: he went away from me up the hill at Ballacraine like I was going backwards. However I saw him turn into Parliament Square, so there isn't that much in it.
What I love about the Vin is that if I pop it in to top at about 40 mph, I can cover an entire journey without changing gear again until it's time to stop, without feeling I'm "holding everyone up". Oh joy : a bike with four gears that could probably manage with two, first and top......