Ha, funny how forumites still believe Mikunis were all made in Japan. See my link below for Mikuni production sites, seems no motorbike carbs are made in Japan at all since long time. Instead some sites in China, in Taiwan, Thailand, India etc. . So not a great argument for insisting on buying from "official" dealers, unless you need certain spares later that you could not find at Aliexpress. At less than € 50.- per carb what´s the big risk in trying their carbs on your bikes. "Precision" instruments - Amals - yes, I cannot tell much about "China" Mikunis, had a look at one "original" flat slide Mikuni, was not impressed about fits. We had a PWK carb for looking inside, a Keihin design it seems with a semi flat slide, no big flaws found but not tested yet, dirt cheap. Slide fit was acceptable for a sort of "flat slide" I guess, but I would not want one for a classic.
For our restored 2.3l Capri I got a new China Weber carb for a 2.8 l at € 110.- as we had troubles with blockage in some complicated drillings in the original old Solex carb we were unable to clear. I put a lambda sensor test kit on for carb tuning on the 2.3l engine, allright for quite some time I think, tried some jets and modded pilot jets to go on the China copy as original Weber jets were a bit different, no big deal. So chief pilot Helga is fine with it , there are limits about what you can do on car carbs having no needles like with motor bike carbs for part slide open. Anyway, with spirited driving , 120 kph on country roads plus 140 kph on autobahn we see 9.3 l fuel per 100 km . I am not authorised in putting SU carbs on like on the Jag. So it is like it is, China not to blame. The copy was € 110.- compared to € 500.- for a new Ford Weber spare.
As to boycots, a bit hypocritical about China I think. Xi is not China, Castro not Cuba, Chomeini not Iran, Putin not Russia, Trump not USA. Factory workers can do pretty nothing about their bosses and politicians but live from products exported. As to China, you would not get a lot from your pharmacy when insisting on medicine made in your country . . .
Vic
Mikuni sites
PWK semi flat slide
PWK flat slide carb, Keihin design:
Ford Weber China: