KLX250s 06 new exhaust and bore job...jetting help

Okay so I finally got my motor back...it's all bored out! 300cc :confused: woop woop. And I just also purchased the FMF powerbomb header and the FMF Powercore 4 slip on. I am keeping the stock CVK carb but I need to replace the jets. I am in Arizona, I have the airbox lid completely off, I HAVE NOT done the crank case breather mods, and I won't really go to too high of altitudes so if some of you carb gurus on here could help me out with exactly what to purchase it would be very much appreciated! Also pics coming soon after everything gets put back together :thumbsup:

Okay so I finally got my motor back...it's all bored out! 300cc :confused: woop woop. And I just also purchased the FMF powerbomb header and the FMF Powercore 4 slip on. I am keeping the stock CVK carb but I need to replace the jets. I am in Arizona, I have the airbox lid completely off, I HAVE NOT done the crank case breather mods, and I won't really go to too high of altitudes so if some of you carb gurus on here could help me out with exactly what to purchase it would be very much appreciated! Also pics coming soon after everything gets put back together :thumbsup:

You can just buy the Dynojet kit, it comes with a new needle and spring which help. Or you could just buy some jets and do a little trial and error. Just get the next couple sizes up on the main and pilot. Jets R Us has flat rate shipping so shipping costs the same for one jet or 20.

Seeing how you had some custom work done, I think you're going to be forced to learn how to tune a carb to get it dialed in.

The FAQ over at jetsRus is a good place to start.

My KLX started out as a 300 and had a 128 main and a 35 pilot in it. I do agree with getting a dyno jet kit and learning to be somewhat familiar with dialing in a carburetor. I use plug color as my guide. With a CVK it is pretty simple.

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