Primary carburator

OK, does anyone know if there is a primary carb on a kz650? if so which one do I synce to? Or does it matter at all?

usally with slide carb's they dont have a specific carb that is locked try to get them to the ideal of 18-20 inches of mercury get one to that and match the rest to it as close as you can c.v carbs are usally no.3 carb that is locked ans some aftermarket carbs as well 33 mikuni smoothbores for instance. hope this help's

Hi, thanks not sure if it even had one just checking I've got 24 - 26 cm of vacuum they sync just fine.

good awesome vacuaam means your motor is in great shape. i always use the carb sync as a indication of engine condition. the high the numbers the better the shape but i always aim for taround the twenty mark if possible it seems to give the best throttle response and drive ability seems to be better as well.

thanks I somehow think that might be my exact problem after I did the sync I no longer have a high 2-4000 rpm on full choke still starts bike but won't rev like it did before. Every time I try and drop the vacuum level the #4 carb goes up and I can't drop it so I settled on @24 to 25 as my set point. not even sure it that has anything to do with it.

The KZ650 FMS's I have call for 19 - 24 CM HG with a variance of no more than 2 CM hg between carbs. So it sounds like your just a little on the high side, but not very much. Ed

Yes that what I read in my FSM too. But I figured more is better maybe not in this case. Will have to revisit the carbs again and attempt to adjust lower vacuum setting.