Does this sound to lean?

[zack221]

I have a 1997 cr125 with a keihin pj carb and i am going to be running a 45 pilot jet in it and 3turns out on the air screw.But this sounds like it will be way lean.My elevation is 2000ft above sea level.The reason i am changing is because the pilot jet in it now is a 50 and it bogs on take off but once it hits the powerband it runs great.So my question is do you think a 45 pilot jet and 3 turns out on the air screw will be too lean for my elevation?My elevation is 2000ft above sea level.

[division4thor]

i thought the pilot jet only had to do with idle, and deceleration....

[zack221]

pilot jet is idle to 1/4 throttle

[joshyz125]

The best way to check it is by checking the color of your spark plug,


You said it does it when you take off. When your taking off easy i'm assuming? Coz like you said, the pilot does idle to about 1/4 throttle.

[zack221]

It bogs up until 1/4 throttle then once it hits the powerband it takes off.I have to rev the crap out of it to get it to take off without bogging.Im thinking it is just running rich right now but the 45 pilot jet should be in today so i will see if the 45 pilot helps it.Right now the spark plug is real dark so i know its running rich.Heres a pic of about how my plug looks.

[joshyz125]

what is the stock size pilot jet?

[zack221]

50 is the stock pilot jet

[krt400ex]

Originally posted by zack221
It bogs up until 1/4 throttle then once it hits the powerband it takes off.I have to rev the crap out of it to get it to take off without bogging.Im thinking it is just running rich right now but the 45 pilot jet should be in today so i will see if the 45 pilot helps it.Right now the spark plug is real dark so i know its running rich.Heres a pic of about how my plug looks.

well something isnt right..cuz my buddy has a '97 CR and the thing rips right off idle until the it screaming and cant rev any farther