Carburetor

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Welcome to the forum. I suggest adding your location below your screen name. That may help getting assistance from someone near to your location.

There are so-many things which can affect your idle:
bad gasoline
poorly synchronized carburetors
dirty air filter
dirty fuel filter
plugged carburetors (pilot jets, controlling low speed/RPM operation often the cause)
sticking pistons in the fuel enrichment system
torn CV carburetor rubber
leaking O-ring(s) between VBoost manifold and cylinder head(s)
leaking rubber donuts between air filter box and carburetors
leaking rubber donuts between airbox and VBoost manifold
leaking VBoost manifold rubbers going from front to rear cylinders
float level not set properly

and many more things are possible. These may happen together (more than 1 thing mentioned)

Read up on your bike: http://vmoa.net/VMX12-Service-Manual01.pdf

VMax carb boots.01.jpgVMax carb choke out of adjust..jpgVMax carb enrich. piston.jpgVMax carb float area.png
VMax carb floatlevel bowl off.jpg
VMax carb kit.jpgVMax carb synch tool.02.jpg
 
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It would be helpful if you let us know what you have tried to rectify the problem.
True. Redan the carbs it was on stage 7 put it back to standard with the jets 150 and 152.
Put new dighrams synchronise them cleaned all up .
Idle 1500.
 
Can we assume that you are returning the carbs to the OE spec?
Were the replacement jets Dynojet or Mikuni, did you also change the needles and pilot air jet?
Do you still have V Boost?
Have you checked for air leaks?
 
Can we assume that you are returning the carbs to the OE spec?
Were the replacement jets Dynojet or Mikuni, did you also change the needles and pilot air jet?
Do you still have V Boost?
Have you checked for air leaks?
Back to mikuni spec back to standard.
Air leaks I have checked nothing. I have to check on the choke
 
Does it make a difference if the needles are not OE
It will, yes, in many instances, especially if you choose to buy a Chinese-sourced jet kit. They just don't work well. Going to a 150 or a 147.5 main jet is often able to eke-out a bit more power, w/the OEM needles because you're leaning it out. That's keeping the OEM airbox and other jetting, both fuel and air.
 
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