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jetting recommendations for a 2005 cr250

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I picked up a 2005 cr250 in pretty much stock form. Seems a little rich on the jetting.

Anyone have some jetting recs for me to start with? I am at a 500-1000' ASL and around 40-60 degrees farenheit.

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I have a 2006(it's basically the same bike) Cr250 and mine is running slightly rich at 32.5 pilot jet- richer needle(marked blue in JD kit)3rd position and a 410 main-air screw varies but it usually runs 2-3 turns out. I'll probly be going back down to a 400 main jet to see if I can clear it up alittle. My elevation is 100-300 ft. so your jetting should be alittle leaner than mine. But remember the colder the temp. the richer you should go with jetting.You might wanna try the stock pilot jet with the leaner needle(marked red in the JD kit)stock position and then try the 400 Main jet, although the 390 might be alittle better and try the air screw around 1.5 turns out. I'd start there and keep an eye on your plugs and the end of your silencer for spooge(if your plugs fouled or black and wet your rich if your silencer tip is wet with black tar looking stuff your rich).

Good Luck!

( THE JD JETTING KIT IS REALLY WORTH THE MONEY!!! )

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I picked up a 2005 cr250 in pretty much stock form. Seems a little rich on the jetting.

Anyone have some jetting recs for me to start with? I am at a 500-1000' ASL and around 40-60 degrees farenheit.

Ut Oh ! Whatcha ridin this weekend? Game on.

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nac-nacer

I just picked up the bike last night and intend to try it out this weekend, so I wont have time to pick up a JD jet kit yet. Am just hoping to get it close this weekend.

Rick

Sold the xr400 and was looking around for KDX's, but came across a deal that was too good to pass up on the CR250. I am going to try and get it tuned in a little better jettingwise on Friday. I will be bringing the ktm200 too.

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Well your stock needle should be fine for now but you can turn your air-screw out to about 2-3 turns out and go to your dealer and ask for a 390-400 main-jet, then swap them out. During your break-in check your plug during every cool-down cycle; if its very dark black and wet your rich( so what ever throttle position you rode in adjust the jetting for that area). If your plug is sighly black to a brown tan your good!!

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390-400? It has a 420 in it along with a 40 slow jet, the air screw is out 1.5 turns. I havent checked the needle position yet.

I am headed to a friends cabin tomarrow morning and we are going to go thru the plug checks to check the jetting.

I picked up 380-410 mains and a 35 & 37.5 slow jets to test with.

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