Try our new info resource - "Aladdin's Cave" (Main menu)Just added a separate link to Ash's Dropbox thread (shortcut)
How big was the hammer you used to remove the rotor? ......I'm scared of you.
I assume the upper half case was upside down when you started assembly. Did the Crank rock freely when sat in the Crank mains with assembly lube applied? I am assuming it not significantly different to a 400/4. ICan the Crank be fitted in the wrong way round.
You did put the shells into the cases with cases and back of shells dry didnt you,mixing up shells would not normally lock it up, i have built with all tightest shells before now with no problem.Primary shaft needs to be fitted and cam chain free but should turn by hand.You havent tried to miss match cases?