Carb guru's....please step in!!

[CatatonicBug]

IIRC dino key does not have a kit for the early style cabs, only the later carbs.

That's correct. No need to use a kit for the early carbs since the needles are adjustable, unlike the later carbs.

[DGXSER]

Yep, the pilot air jet and pilot (fuel) jet play a part really throughout the RPM range IMHO. They are not nearly as effective once the needle starts rising up as the percentage becomes so minimal.

The needle does effect low rpm ranges. I installed one of the four in my first set of carbs with the spring in the wrong position. That one cylinder would foul out to the point of a constant miss when I ran in the 1000-3000 range. Above there the plug would clean up and run. Fixed that needle and it ran smooth at all rpms.

I've personally only owned the 81 model and had the 81 model carbs on them. I can tell you that if you know how to tune them and synch them up correctly, I have no doubt you can get the same performance as the dynojet kit provides. Not having put one in a bike, I am really saying I have no issues getting mine to purr like a kitten and run liked a raped ape without it.