OK this topic is interesting enough for me to join the forum. Dinqua, you are one dedicated experimenter, many thanks for sharing all your results.
Forgive my ignorance here, but I thought all the direct action carbs worked a lot better with accelerator pumps because when you whacked the slide open you dropped the vacuum and hence induced a transient super lean condition. I thought this was the big problem with the Keihin CR carbs (which don't have pumps) and was solved with the FCRs.
Haven't really studied the Mikuni TMs but I guess they're the original flatslide. According to the Sudco catalog they're available both with and without pumps, and there's also some optional jet for use with two strokes. Very cool stuff, I'm very anxious to hear how it works out.
