The current flywheel is 110mm dia and is too small I think. Like everything on the bike I'm up to about version four I think. I originally used a small KX250 wheel which was waaaaay too light. Next I went to the one pictured, but without the holes. It was much better but welded itself to the crankshaft so after that I drilled it out to get some weight out of it. It worked fine after that but I got fed up with magnetic pickups and Hall Effect sensors and their susceptibility to EMI so then switched to an optical trigger and the current flywheel. It's pretty good as is but I think I'll add another 20mm to the diameter.
Thank you for the kind words, to be honest though big balls aren't a requirement. Seizures aren't instantaneous and if you're paying attention - and you should be - there's time to pull the clutch before it locks up. And besides, the little bike is beautifully stable even when it's spinning the wheel, it's really not hard to ride.
Will the Pursang flywheel and stator fit? If so it'd be a quick and easy way to get it onto the dyno without the distractions of the Zeeltronic setup. If you use the Zeel I'd be inclined to just set it up for a fixed or straight line timing curve. A curve will make hardly any difference on the strip and will just take your time and attention away from more important things.