I have a CRF450x my 08
it is modified the air box and a Leovince X3 exhoust

chengin the spark plug i found it white that means lean carb
how can i tune it?

ther is not a tuning table in the instruction manual

my actual setting:

Max 162
Min ??
fuel screw, 2"
Needle NKJU 2"

thank's in advance for Your eventual suggestion

Read the stickies at the top of the forum.

You CANNOT read a plug to determine jetting, unless you are an expert, use race gas, and do a plug chop.
Plug color reading is done in (4) places on the plug, the tip is not the primary place: it is the base of the insulator.
Reading the tip tells you 'plug heat range' more than anything else.

165
45pilot
NCVS needle 3rd clip
50 leak jet
Apump adjustment

You adjust the fuel screw for max idle. If it's more than 2 turns, you need a bigger pilot jet. Less than 1, you need a smaller.
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