Strange... although the link says 550, the picture says: fits CB500F. I wonder if that needle in the set has a number stamped in. The stamped in number for the OEM CB500 needle is: 272304. That same needle is in the 550K models, except K3 and K4 that have PDcarbs. For the OEM CB550F needle the stamped on number is: 273004.
I don't recognise the little cylinder and that little ring.
A few comments. No need to worry about that air screw spring. You can easily find one. It's not that critical to have the OEM spring. You could also use loctite, btw.
Then there's the slow jet that looks different from the original. There have been several posts about them.
In general the advice is: use the genuine Honda parts. They hardly wear if at all. All parts in my CB500 carbs, except for some rubber seals, have been in there for over 130.000 kms and still don't show signs of wear. O-rings need to be replaced sometimes. Especially the little ones around the main jets should be in good order. If that one leaks, that cylinder will run rich. You may check the tower for cracks. The set in the picture doesn't show the O-ring for the drainplug, but that one will still be OK, I guess. What makes you think you need to renew jets and needles?
