Idle 1998 yz250

I'm new to the forum,so hello everyone

I have a question about correct idle adjustment.

When I start the bike cold the idle appears to be normal after about a minute or two when the motor warms up the idle appears to pulse up and down, goes into some kind of cycling with pinging. When I adjust the air/mixture(richer) screw the idle returns to normal no cycling/pinging, but the pilot air screw is now turned in, all the way. The bike will continue to run for about 2 and half minutes the carb will load up and finally turn off. Do I need to change my Pilot jet or Jet needle postion. Jet needle postion is second from top.

thanks, for all help that is given

Edited by Brandon100XR

you need a larger pilot jet, so raise it to the one above the one you have now.

Thank you FoxySox, I changed the pilot jet. The previous owner had a #42 and I changed it back to stock. #48. I will try the changes later tonight.

Edited by Brandon100XR

48 will most defently be to rich ( like everything from the factory) it should run its best between 1 to 2 2/4 of a turn out, hope it helps

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