KX Riders

Maintenance & Technical => KX250 / KX125 => Topic started by: lessongeo on March 22, 2021, 12:41:42 AM

Title: 2004 kx250 two stroke jetting ?
Post by: lessongeo on March 22, 2021, 12:41:42 AM
People:

After some 4 stroke owning and riding, I decided to go back to two strokes - more specifically a 2004 kx250.
Seems to be a decent bike, and was excited to get it out this past weekend.

Here's what I found out:

Rode in 40 -60 degree F temp
3000 - 5000 ft elevation
Single track rocky mountains - 2 hr ride

bike idled decent, low end was there. Top end was fine -- not that I ever was too wide open riding single track. The middle was a little flat and had a big bog from 1/4 throttle to opening throttle quickly.

I opened up the carb -- looks to be stock with all the electrical gizmos attached. What size is this thing - a 36mm or 38?? ?

Here's what was in it:
number 8 slide
45 pilot
155 main
unknown needle (markings gone) on clip #2

plug was a BR8eix - some carbon build up but I've seen worse.
Pipe didn't have that much splooge dripping from it

I am told a stock motor with a fairly recent rebuild with a gnarly pipe and fmf turbine core 2 spark arrestor

I also found some JD needles included with the sale - red and blue.

Hopefully the KXriders can help me out.

Cheers!