FLAT CR carb jetting general settings?

Hi all... I have a 04 CRF250X model... I have been searching all over the net to try and understand the general rules for a flat CR carb jetting.. most have there own ideas of what runs good at what sea level etc...

Im looking to find out the FACTS /general rules to what jet numbers to use to stay in spec which each other when changing..

Im at sea level in Brisbane , Australia...

1. pink wire mod done.

2. Airbox top cut out..

3. standard exhaust

Some are using a range of MAIN jets between 148-165..

Is there a rule of thumb in numbers Ie, 160 main jet 42 pilot jet, if changed one would the other have to change??

In my bike i have the

1. Main= 168,

2. pilot = 40.(i think its the pilot)

3. one of the Two jet around the main .. 80( carnt quite make out number but looks like 80)

4. There ia also another jet that on the air box intake side, slightly of centre... This one is 100...What is this one??

40,is the pilot.- part of the idle circuit

80 is the starter jet - Used only when the choke knob is pulled

the 100 is the slow air jet works in conjuntion with the pilot jet and fuel screw. Is nearly never changed.

Jets are only changed to resolve a particular problem.

You change jetting when:

You make a substantial change in air pressure (altitude)

You make a minor or major change to any intake or exhaust.

Stock jetting is fine for a stock bike

If you uncork it you will need to change the jetting.

Go read the pinned FAQ;s in the 250X forum.

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