trx400ex jetting to 440 big bore

I have put a big bore 440 on this trx with a stage 1 cam. The elevation here is2500ft . The machine has a 165 main jet .I was wandering what jet if neccessary to change to.The atv is stumbling in the mid range and i have moved the clip up and down with not much change.

Eddie or William can give you definitive answers, but I have found that the 440 kit on my DRz required both a smaller main as well as pilot. Moving the needle up or down will change the point at which the needle allows more fuel only at low throttle - so probably too low to affect the problem you're experiencing. I'm using the 152MJ and 42PJ with good results. Eddie has recommended the EMP-3 needle to me.

Also, as you probably ride in high density altitudes you will need to lean your carb even more (due to the combination of atlitude and temperature) like I did at higher altitude and lower temps.

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