New jets came with the Septres, so I would guess if someone was paying close to $600 for mufflers they would have changed to the Team Triumph recommended jets. What does your bike idle at and what are your AF screws turned out to?

Also, I may be wrong, but I thought opening the throttle was not advised when starting.

Once you've got this sorted out, balance the carbs, you'll be pleasantly shocked.

Every normal man must be tempted, at times, to spit on his hands, hoist the black flag, and begin slitting throats. H. L. Mencken