Jetting and race fuel

[smahala1286]

I want to try out race fuel in my kx125, what do i have to do to my jetting? as of now i am running a little rich on 91 octane pump gas at 32:1, i also live in colorado at high elevation.

 

[Senior KX Rider]

Depends on what type of race fuel you are going to run. On my KXs to run C-12 or something similar I go down 2 on the main from stock. 1 on the needle and 1 on the pilot. To runb an oxygenated fuel like U-4 or U-2 I go up 1 on the main from stock and 1 on the needle

 

[smahala1286]

cool thanks