An excellent job! - Well done Sir.
How about a few nice little brass oil-pots on the crank main bearings and other strategic locations? I always like to see lots... and especially when someone makes a central feed to the big-end of the crank, so you see a small diameter brass tube from the end of the crank-pin to a collector that is at shaft centre, with a separate oil pot and feed pipe to drip into the collector. Odd little details can personalise a model and entertain us lesser mortals.
But well done!
gg: Maybe a single drop of Loctite screw-lock will ensure it doesn't move on the shaft anyway?
Personally, I would remove and silver solder the flywheel, IF it needs to be repaired. Then carefully ream the hole back to size. (The Cast Iron may shrink very slightly with heating, or it may not be significant to affect the sliding clearance onto the shaft? (N.B. Cast iron exhaust manifolds can shrink 1 to 3% in their lifetime - but after many heating cycles... - Maybe the carbon is burnt-out by heating? Can a material scientist explain please? A curious material! - I once bronze brazed the skirt on an engine cylinder with a short (1") crack in it. Afterwards the skirt was thou or 3 smaller than the rest of the bore. - The piston was a good fit in the top 3/4 (above the base flange of the cylinder), but tight for the last 1/2" or so, A judicious application of emery where the engineer's blue indicated made a good fit, but a house moved forced the sale before I got that bike built and running, so I don't know if the repair worked...).