Problem starting when engine is cold.

Check the condition of your reeds. This is a very common cause for hard cold starting.

I’m I right to guess that the air temperatures in your area have recently dropped more than about 15 degrees and prior to this you had no problem starting your KDX? If that’s the case then chances are good your only problem is a lean pilot circuit Try turning in the air screw some and see if that helps. You’ll need to richen it quite a bit so try a fairly bid adjustment say 1 or 1.5 full turns in and check the effect on starting. If you find the air screw is almost completely closed but its still not starting easily then you’ll likely need to install one size richer pilot jet If you find that that richening the pilot circuit is doing little to improve the problem then you’ll need to look at other possible causes. This is however them most common problem as the air temp cools.

I’d expect that if the pilot circuit is lean enough its not stating easily you are also seeing a slight bog/ hesitation when you wick the throttle open . Is that the case?

For more details on how/why air tempo effects jetting you can check out the JustKDX home page and have a look at the tech tips section.

David