[Nasher]

The lighter springs that come with the Dynojet kits are to allow the slide to open more quickly and quicken response when opening the throttle, and could cause the issue Jerry has.
If he wants the bike to go back to idle quicker a stronger spring is in theory required.

I’ve just rebuilt a set of carbs, fitting a Dynojet kit at the same time, and considered putting the standard springs back in with the Dynojet needles and jets, as even on the bench the slides were so much slower to drop back down. I stripped them again, cleaned them again, installed new diaphragms, and finally got them to close a bit quicker, but still not as quick as with the standard springs.

My kit didn't come with a drill to open up the holes, and it was not mentioned in the instructions.
Flip, do you know what size drill it was?

Nasher