Needle adjustment

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schumiruby
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My Bike: ZXR 400 L5
Location: Chesterfield, Derbyshire

Needle adjustment

Post by schumiruby »

i had my 1995 model dynoed yesterday and was told it was running lean. asked about putting bigger Main Jets in and he told me that i could adjust my needles to achieve the same result. can anyone explain how this is done and if at all it would have the desired result. my bike is standard except for a K&N filter and a Carbon Can Co. end can!
cargo
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Re: Needle adjustment

Post by cargo »

You can raise or lower the needle by changing the position of the circlip on it.
There are 5 maybe 6 grooves on the needle
schumiruby
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Re: Needle adjustment

Post by schumiruby »

im running lean! do i raise the clip or lower it?
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mick41zxr
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Re: Needle adjustment

Post by mick41zxr »

Raise them. Also can be done with washers.
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jake
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Re: Needle adjustment

Post by jake »

i dbe surprised if the needle needed richening? it would be a first for a zxr that ive heard of tbh.
sort the main jet out first, then come back to the needle.
schumiruby
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Re: Needle adjustment

Post by schumiruby »

thanks for your replys! i think ill go for 102.5 keihin jets then. how does that sound?
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jake
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Re: Needle adjustment

Post by jake »

id give the carbs a good clean, get an airline thru the jets,etc.. carb cleaner. check the fuel filter too
what size is standard on a 95 L? import or uk? id go up maybee 1 or 2 on the mains from whatever is standard
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mark400
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Re: Needle adjustment

Post by mark400 »

Surprised your Dyno guy didn't have jets, but I guess eventually they won't be needed at all....
There is little point playing with the jetting without being able to read the fuel/air ratio - I would either buy a large range of jets 4 x 100 / 102/105/107 and take them with you next time(expensive) or just go to a dyno that stocks jets.
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