2009 KLX250S with FMF Q4 air box snorkle removed.

I'm about to order the KLX300 dynojet kit with more aggressive needle.

I'd like to jet it to run under 3000` but would like to run Pikes Peak 14000` if needed.

Can I jet with the air box cover on for low elevation and just remove the cover for high elevation?
comes with 120-124-128-132 main jets
or would the 09 250 dynojet kit be better?
any ideas?

 

Nope, would work the same with either kit.

I personally like the needle in the 2206 kit as well. Below 3000' I typically recommend a 128 main jet with the usual exhaust and intake mods. Go up a lot in elevation and you will have to take the lid off. Some guys run a 132 with no airbox lid but it runs pretty rich and they are all at sea level.

I run a 124 main and it is just about perfect. I did swap in a 128 but it made no performance difference and started running a little rich. I am at 3500 elevation and run a big snorkel and a lid.

 

Hey BigSky:
Are you running the stock #35 pilot? Which clip position on your DJ 2206 needle? Thanks.

 

I am running a stock pilot (#35) and my needle is on notch #4.

Right now if fires right up without touching the throttle, starts very easily even when hot, no soot buildup in the exhaust, absolutely no popping on deceleration, it doesn't cut out under full load or high speeds, and it is getting about 62 mpg. So it has to be just about perfect jetting right now.

This fall I am doing a big bore 351 and I will most likely go with #38 pilot jet and a #128 main. Don't know if I will have to change the needle position. I did try a #128 a couple of weeks ago and it didn't work as well as the 124. I thought for sure I could go up one more size on a stock bore and I probably could if I went without a lid on the airbox.

 

Thanks. Is that notch #4 when counted from the top (blunt end) down towards the tip (point end)?

 

So if I visited the mountains for a week a year I could just leave the 128 jet in place remove the lid and be good to go?

 

I would bet you could. I leave mine alone on my annual 2-week CO trip, and I go over 12,000 and 13000 foot passes all the time. My KLX is now a 300 with a full Muzzy exhaust, open airbox, 128 main, DJ needle and kit, needle in 3rd clip from top, 35 pilot, and Kouba air/fuel screw. I didn't even have to putz with the Kouba screw while there.

 

Yes sir, that is correct

 

So set it up like DJ recomends, but let the air box lid on and go with a 124 main?

 

Sadly, every bike is a little bit different and every elevation and climate is a little bit different. I went by what Dynojet recommended and got it dialed in really close. I think I am just lucky in those regards.

Your bike will run with any jet from the kit in it. If you are close to sea level you can run them a little bit fatter. A 128 would suit you just fine. If you are worried about upper elevation issues, throw a 124 in there, it will run great either way. I tend to like things a little bit on the lean side. Some guys like it better on the rich side.

So follow the instructions and put in what you feel you want. A 124 or a 128 are probably your best choices.