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Discussion Starter #1
Hey have a 2005 sportsman 400 I read that they have problems being jetted to rich from factory. My Question is i got a uni filter in it now. I just got a full Dg exhaust. Do i need to rejet you think or will it be good.
 

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Do you know how to read your plug?? You probably need to go one size larger on the main jet is all.
 

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Discussion Starter #3
Ya i no how to read plugs but read around that its hard to read plugs useing unleaded gas. I did my kfx 400 with alot of changing jets in and out till it ran perfect. But that was a hell of alot easier to work on carb than the sportsman lol
 

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The best thing to do would be to replace the needle valve, as it is likely worn, which will cause the engine to run rich. Then, install a Dynojet jet kit, with the settings for your elevation, and the main jet recommended for your pipe. A pod filter does not flow as much air as a stock paper element, and especially an oiled gauze filter.
 

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The needle has nothing to do with the top end. If you change out the air filter and the exhaust you have to rejet, period! At least one maybe two steps on the main jet. Just do your plug readings, I know it's a pain on these things, but it'll pay off big when you get it right! (Mine took almost a month, but its spot on now!)
 

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Go to the for sale section and start your own post. Your looking in the wrong area and high jacking others problems. That's your best bet bud.
 

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Discussion Starter #7
Was looking to buy a dynojet kit but when looking up the kit the Dynojets that come in the kit are smaller than the stock ones in it. I know the numbers from dynojet to mikuni are different. When i look it up they are smaller in comparison. It has me confused i think im just going to buy a couple of main jets instead of kit.
 

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That's what I'd do also.
 

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The dynojet kit jets sizes are different because the needle is also changed. That effects fuel flow through the entire range, if the needle is changed the proper dimension. Anyone I know with a carbed street bike swears by the dynojet kits when adding aftermarket exhaust.
 
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