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Hey guys,

I need some clarification and/or advice.

I have a 2005 CRF450X. Just got a JD kit and installed it. I have a few questions.

I live in Denver CO. I ride at 5000-12000ft - Per the instructions I've put the red needle in, 3rd clip position and I used the #160 main.

I have the following mods:

1. FMF Titanium Powerbomb Exhaust with FMF Megabomb header
2. Full airbox mod, top and side - Twin air filter
3. Backfire screen removed
4. I did the AP mod as well
5. Pink wire isn't done - should I?
6. 45 Main, stock
7. Stock leak

As I was reading the instructions I saw the section that talked about racing mods and to use the #170 main. I'm assuming that is for sea level. So if I'm running a #160 should I run a #165 with all my mods?

Anyone riding at this altitude with similar mods? I didn't find anything in the jetting section.

Thanks for the help.

Most of my riding is at 5000-10,000 ft I use the following and it works really well:

165 main
JD needle 4th from top
45 pilot
1 1/2 turn out on the fuel screw.

You don't really need to do the pink wire mod until you put an R cam in or hot cams.

What mods do you have?

check out my garage...

Open air box
Ti4 pipe
FMF power bomb
Twin air power flow
boysen QS2

Got it. Runs perfect.

Year: 2005
Model: CRF450X
Elevation: 5000ft-13000ft
Temperature Range: 20-100 degreees
Smog (AIS): N/A
Airbox Modified Top: YES
Airbox Modified Sides: YES
Backfire Screen: REMOVED
Air Filter: TwinAir
Pilot Jet: 45 Stock
Main Jet: 165
Needle: JD RED
Needle Clip Position: 4th
Fuel Screw Type: Storm
Fuel Screw Setting: 1 1/2 turns
AP Modified: O-Ring
Leak Jet: Stock
AP Cover: Stock
Exhaust Type: FMF PowerBomb TI with FMF Megabomb Header
Exhaust Modified: Full
Pink Wire Modified: NO

Awesome! Glad to hear it. Have fun twistn' it

Don't forget to keep an eye on your plug to see exactly how she's running.