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Hi I have a raptor 660 I recently installed a pro design air filter and full hmf exhaust I am running with the air box lid on I need recommendations on jet size,pilot jet size,needle position,pilot screw position thanks
 

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A jet kit will give you better needles that you cannot buy seperately.
Depending on elavation and air temperature, and if you remove the airbox lid, will determine if stock pilots will do, or if you need to go to 25's.
Main's will vary depending on the above(as does needle position).
140s-150s will be ballpark.
The right carb(thumb throttle side) takes one main size bigger than the left(both pilots and needle positions should be the same).
Also, search for "Clear tube method"
as that shows the only correct way to set both float's height.
There is some trial and error and a learning curve to proper jetting.
Generally speaking, the pilot controls idle to 1/4 throttle, the needles control 1/4 to 3/4 throttle, and the mains 3/4 to wide open throttle.
But, there is some overlap, and they do effect one another.
Clear tube method and aftermarket( needlesDynojet) are a must for good performing 660 carbs.
The pilots will be stock 22.5 or next size 25's in most cases(you need a pretty healthy build to need 27's)
The needles will likely be 3rd or 4th groove position(of the 5 grooves), and leaving the mains for most of the adjustment.
With free flowing exhaust and intake, and temp/elavation/condition dependent, the main size can vary quite a bit.
Go with a Dynojet kit, search for "plug chop", to see how to read your sparkplug, and that will help you fine tune, and know if you are too rich or too lean.
It's always good to go rich too.
Because it easy to tell, and hard to cause damage.
There's an old saying " leaner is meaner", as an engine "can" run good lean...while it's running extra hot and burning up engine internals.
It's best to error on the safe side and back off.
 

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I'm in Phoenix and run 25 pilots, 175/180 mains, and my needle is on the richest setting. I am running the stock mikuni needle right now tho.
I have proflow filter adaptor with foam filter, no lid, full Yoshi exhaust.
She runs great too. Just beat a 700 with baffle out.
 
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