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Discussion Starter #1
all the information i see for jetting a vstar 650 say the carbs use the mikuni small round jets, even the dealer sold me the small round mikuni jets for my 650 classic but when i opened the carb their are 2 #90 large round mikuni jets they are definitely OEM they fit the emulsion tube perfectly, the small round jets have exactly the same dimensions as the large round except head diameter , it looks like you can use either one on a 650 has anyone else opened the carbs to find the large round 8mm instead of the small round 6mm that is supposed to be there???, i don't get it, why mine has 8mm jets
 

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Don't quote me but i thought i read or heard somewhere it was a change after a certain year. Don't remember which way or what year it changed. Now I'm racking the brain to remember what exactly it is i think i read.
 

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Discussion Starter #3 (Edited)
Don't quote me but i thought i read or heard somewhere it was a change after a certain year. Don't remember which way or what year it changed. Now I'm racking the brain to remember what exactly it is i think i read.
there's a youtube video from cruiser customizing showing a 650 being re jetted and plain as can be a large round was removed and a small round installed, i asked about it and never got a reply from them, i was thinking like you that earlier years maybe used large jets and later they switched to small jet, i think i got it figured out on carbs that use fuel cutoffs the main jet screws down into the emulsion tube where only a small round jet will fit, so on bikes with the fuel cutoffs you must use the small head jets but bike without cutoffs you can use ether a small or a large
 

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That sounds familiar and makes sense
 
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