FYI, have you been searching for a solution to the all too common float needle/seat leaking with OEM/Aftermarket sets? Try this. Keihin 82-83 Sabre/Magna float seats and needles. Bizarre that a Mikuni could match-up with a Kehin but it happened. Advantage of Viton-tipped needles and same static setting. Ditch the seat filters and use the OEM sealing washers. Works out perfect for the early series VM-28 carbs. Aftermarket sets do not distinguish between these two models(Sabre/Magna) but they clearly do have different fueling issues. The Sabre is Gravity fed and the Magna is Pressure fed. Thus the Sabre has a float fueling orfice larger than the Magna. A typicial Z ranges from 2.0-2.5 depending on manufacture. A typicial Magna float seat is just a smidge smaller, approx. 1.5, and the Sabre maybe 2.8-3.0? I have not tried various aftermarket designs or measured the opening, yet! Just a bit of info. Thanks, Clay