problem with km63 carbs

my buddies bike has a set of km63 on a 77 kz1000 ltd an its is leaking fuel out of overflow. i pulled the bowls off an checked the float level an they were off but as i cleaned them back up on the main jet tube where it screws in carb is leaking air around the threads. he tubes are the non o-ring style. any help would be grat thanks

I screwed the tubes out and the threads look good an carb isn't cracked

63 kilometer carbs sound a bit large, maybe try some 29 millimeter smoothies; or even the dreaded 34 mm BS carbs. All kidding aside; what are km63 carbs? ed

Mikuni 36s read backwards by a dyslexic.Lol.bj