82/83 Kz550H1/H2 (Gpz) models in the U.S. came with early TK26 carbs using non-adjustable 4X31 needles.
82/83 Kz550H1/H2 (Gpz) models in some countries came with early TK26 carbs using 4X30 needles (clip in position 2 from top).
Other Kz550 models using the later TK26 carbs, in the U.S., came with non-adjustable 4A02 needles.
Other Kz550 models using the later TK26 carbs, in some countries, came with 4A00 needles (clip in position 2 from top).
Zx550A models in the U.S. came with TK27 carbs using non-adjustable 4A10 needles.
From available parts fiches, it is unclear if any TK27 carbs came with adjustable needles.
Dynojet jet kit (2107.003) for the 82/83 Gpz 550 comes with a DNO110 needle, which is quite different from the factory needle.
The factory needle for the 82/83 Gpz550 has one taper which starts rather low. The Dynojet needle has two tapers. The first one starts rather early. There is also a straight section at the very tip of the Dynojet needle.
Here's a diagram showing the two 82/83 Gpz 550 needle dimensions.
Here's a diagram showing the relative measurements for the needle relative to the needle jet flow point.
Here the factory needle with ink showning where the taper starts.
Here's both needles together.
