Needle adjustment

[controller]

2003 RM 125.
I live at 5,500 feet in Denver and seem to be running my needle jet at the leanest setting possible most of the time. The bike is stock and I am running pump gas. My question is I am thinking of going to the next size leaner needle to have more adjustment in that circuit does anybody have any wisdom in the area??

 

[A-RustyDemon]

Well the needle taper and O.D. affect the air fuel mixture in the lower to mid throttle range. So if your doing more woods type riding and your rich and those throttle position. Then a change can help. But if your riding fast trails or the track at WOT it'll do little for you. What does your plug look like.. dark brown to black.. light brown? If your looking for some adjustably you could drop your main by a size and move your clip.. to get back to where you are. But if your plug reads ok I say why bother.