What Jets recomended for 01 YZ144?

I just installed a new Athena 144 kit on my 01 YZ125. The jets I took out are 22.5 pilot, and 450 main. I installed a 35 pilot and a 480 main. The motor stumbles before it hits power band and in beginning of power band. I expected some drop off on the top end, but I'm dissapointed with the bottom and midrange. I'm hoping its a carb issue. Any help would be appreciated.

The weather has been between 50-60 degrees when riding. Also using 50/50 mix of U4.4 and 93 octane (98-99octane) with yamalube 2R.

Don't know about the Athena kit, but if your jetting was correct before the kit (as a 125), you should not have to change very much. Sometimes you go leaner, not richer with the bigbore. Basically, it probably should run pretty well with the same as 125 jetting.

Thanks Ralphtogo. You might be right. I put in a 27.5 pilot last night and got my midrange back, but bottom end still sucks. I might end up going back to what it was originally.

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