09 KX250F w/ JD Jetting kit

Hello, sorry I am fairly new to this, I mostly work on race cars, but am offering some help to a 15 yr old friend, friends bike has a JD jetting kit in it. The original jets are in the box with the other new stuff. Stock was 182m/40p NHJT needle. Kit came with 190,185,180,175 mains and a 42 pilot, 2 needles blue one for low alt/low temp, red one for high alt/high temp (were @ 2,000') From whats left in the box ( havn't torn carb apart yet) it appears to have the 190 main jet in it and I think the red needle. Is it just me or does this seem very rich, compared to info I found here, and the "TG" site? Or are the JD needles very different from stock needles. Has a 42 pilot jet in it. Doesn't run bad but I think there is more to be had. What jets are recommended with the stock NHJT needle, or are we better off with the NCYS needle? I have looked at some of the charts and stuff and haven't really seen one using the NHJT needle, either the NCYS which TG recommends, but TG's chart also shows a NCYU needle as stock, or is this a typo? http://www.teamgreennews.ca/pdf/2009_JettingChart.pdf Plan on trying to follow the jetting 201 thread, but would like to get close and see what needle we need to start with.

Any help is greatly appreciated thanks Josh

Any one with any Jd jetting experiance? Called jd jetting, they said there needles are larger then stock but couldn't give me a comparison to anything.

From my experience in getting help with my Carb. Don't assume/guess what's in their now. Take it apart and provide them the proper information to assess your carb issue.

You first mistake is a lot of guess, assumptions and 'what does the other guy run?" You will get no where fast thinking like that.

First, properly adjust the fuel screw for a perfect idle. Then ride the bike, do stead state throttle runs under load. No the problems and the throttle position. Then along with what jetting is actually in the bike, let us know the problems.

What you do not want to do is follow a guy who says cliff jumping is great with out first hand knowledge of the cliff and landing.

They sorted out my carb issue, and got me to order the right parts. Excellent information and knowledge. Parts should be in tommorow!

Bike runs good, we were just trying to determine if there was any more performance there, and why such a large main jet is recommended. It is due to the larger diameter needle that JD jetting uses. Checked valves and shimmed the L exh valve (was .001 looser then spec.) and cleaned the carb, he said it seems alittle crisper now. It does have a 42 pilot and a 190 main, w/ red needle, thin oring on the AP, gonna stick with this setup for now. He has 80hrs on it and wants to get an intake and due an overhaul shortly, so we may have to rejet then. What intake seems to work the best on these(stock right now).

Thanks and sorry for not giving much info before, I was just trying to get a game plan and not have his bike apart for days while we wait for parts, as I said Im new to this stuff.

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