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2007 Ktm 450 Exc

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I am close to purchasing this bike. My understanding is that it is jetted very lean from the factory and I don't want to break it in that way. But of course, I want to ride it as soon as I get it, so I'd like to have the correct needle and jets on hand to get it set up better for break-in purposes. Can you recommend an initial carb setup? According to the Owner's Manual (on-line), it says it comes configured as so:

Keihin FCR-MX 3900E

main: 178

jet needle: OBDVR

idling jet: 42

main air jet: 200

idling air jet: 100

needle position: 3rd from top

mixture screw open: 1.25

My elevation is near sea level (central North Carolina).

I'm hoping you can recommend an appropriate set up so I can have the parts to do the job handy when I get the bike home. I'm not opposed to a JD jet kit, but if I can do the job for the price of a needle and a few jets, that would make me happy.

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I am close to purchasing this bike. My understanding is that it is jetted very lean from the factory and I don't want to break it in that way. But of course, I want to ride it as soon as I get it, so I'd like to have the correct needle and jets on hand to get it set up better for break-in purposes. Can you recommend an initial carb setup? According to the Owner's Manual (on-line), it says it comes configured as so:

Keihin FCR-MX 3900E

main: 178

jet needle: OBDVR

idling jet: 42

main air jet: 200

idling air jet: 100

needle position: 3rd from top

mixture screw open: 1.25

My elevation is near sea level (central North Carolina).

I'm hoping you can recommend an appropriate set up so I can have the parts to do the job handy when I get the bike home. I'm not opposed to a JD jet kit, but if I can do the job for the price of a needle and a few jets, that would make me happy.

The needle that comes in the carb has too little taper. The no brainer fix is the JD kit. The other option is a needle with an "E" (3rd letter) taper. OCEMP is a nice starting point, OCEMN is quite popular but probubly a bit richer at 1/4 throttle then you need. When you go to this steeper taper the main jet becomes much more crticle and will be in a smaller range of sizes, buy jets in a range fro 155 to 162 (do not run those sizes with the "D" taper needle, ever!!!) Then to adjust your criticle 1/4 throttle area buy

OCEMP as a starting point

OCEMQ on step leaner

Equally important to jetting for that break in ride is;

bike level, burp any air out of the head with the blead screw near the spark plug.

then do the same on the top of the right radiator

then set coolant level no higher then 1/4 over the fins in the top tank!!

Then avoid like the plauge tight trails!!! We need wind thru the radiators so when you buddy turns into a tight trail to see how misurable he can make you just cruise down the logging road. Break in does not have to be slow, it needs to have wind

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Thanks Dave! I like no brainer, so I bought the JD kit. :applause: Thanks also for the additional break-in tips!

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