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ready to order - need advice on jet sizes pls

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Hi, I currently have a drilled out stock exhaust with plates removed and 5 holes in internal cap but Im intending to get a new Yosh full system for my 400s 02.

I ride in QC, canada (not in winter!) between 0 - 4000ft tops

temperature range 65-90F

I have done the 3 x 3 airbox mod, have a Klein Air filter and am also intending to knock down my front sprocket to 14.

I have read the forums but am still a bit confused,

I need to order the dyno jet kit right? to rejet After I change my exhaust but just for the needle? as I need to get seperate jets that are not included in the dyno jet kit?

Can anyone recommend to me what size jets to get considering my setup and then Ill consider ordering them at the same time if nessecary.

Oh, Btw any install problems that I should be aware if with the exhaust?

Thanks all

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You have 22.5 pilot jet. Order a 25.

You have a 142.5 main jet. That will probably be fine. You may need a 140 and/or 138.5 with your stock exhaust or if you are above sea level very often.

Use the DJ needle, clip 3 usually.

Experiment with the DJ spring and stock spring to see which you like best.

Order an extended fuel screw so you can reach it to make adjustments.

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