TOPIC:

For those interested:

This is the eBay ad I used to purchase mine ( Size # 82)
Holley Carb Carburetor GAS MAIN JETS KIT 50-109 1/4-32 ANY SIZE U CHOOSE 4 PACK

My auto parts guy could also get them (at twice the price but no shipping charges if I wanted to wait about 10-14 days for their next order to the supplier.)

Apparently the "Holley" Part Number is 122 - 82 . 122 denotes MAIN JET and the 82 is the actual jet size.

Coincidentally, this fellow at my auto-parts store used to be a motorcycle mechanic at several dealerships and when he heard me say I was using them for a Mikuni carb he knew exactly what I was doing with them. Additionally, he told me that the Hard-Start "issue" with some bikes using Mikuni's was well known, back in the day. Apparently Mikuni solved this problem in a similar manner, noting that "air-bleeds" were also threaded for interchangeability so that the carbs could be "tuned" better.
.....and it only took 40+ years to figure this out for the 1300's ?? !!
Better late, then never !

Wonderful news to actually have an unrelated second hand confirmation regarding this issue and based on real historical context from the distant past at that!

Perhaps with the limited numbers of the carburated models produced and sold, they didn't really feel the need to address it. It's only the recent modern times when they seem to gain in popularity and more technical angle attention. There are definitely more KZ1300 parts bikes than on the road!

This mod using unrelated main jets seems to be the best ultimate solution. Can't go wrong with restricting those holes - my bike started flawlessly a couple days ago again and I put another solid 50 more miles on the odometer.

Thank you Scotch and Kawboy!