300 XC and JD Jetting

How does the JD JETTING kit perform on the 300 XC?

I need to re-jet my new 2007 300 XC and all the jets I have are too large; therefore, I need to purchase all new jets for my new toy. Before I run off to my local cycle shop and place an order I am considering a JD JETTIN KIT for KTM. I purchased a JD KIT for my YAMAHA WR250F (which I traded in for my KTM) and ended up going back to the stock jetting. I could never get it to run the way I needed it to run. I am also condidering a FMF JETTING KIT but I have not seen any reviews on the FMF KIT. Jost asking for someone's 2 cents.:confused:

How does the JD JETTING kit perform on the 300 XC?

I need to re-jet my new 2007 300 XC and all the jets I have are too large; therefore, I need to purchase all new jets for my new toy. Before I run off to my local cycle shop and place an order I am considering a JD JETTIN KIT for KTM. I purchased a JD KIT for my YAMAHA WR250F (which I traded in for my KTM) and ended up going back to the stock jetting. I could never get it to run the way I needed it to run. I am also condidering a FMF JETTING KIT but I have not seen any reviews on the FMF KIT. Jost asking for someone's 2 cents.:confused:

It's a good package, works better on the 4 stroke, and costs more than you have to spend to dial in your 300. If you don't want to have to think much about it, get it. But you will still have to make minor adjustments. There is much info on jetting the 300 here and on ktmtalk. Many like the N3EH or N3CH needle. It's your choice, spend $70, or $15-$20.

What's your details, terrain, elev, temps? How do you know you need to rejet, symptoms?

I swapped out the stock needle for the N3CH, adjusted the AS, and my 300 ran great, no spooge.

I am in the high desert with an evevation of 6400ft. with a current temp of 61 degrees. I race HS and desert events 80 percent of the time which vary between 6000-10000 feet and above with a temp of 80+ degrees. My first event however will be in two weeks at an elevation of 4200 ft and about 70 degrees. The desert events here are fast but not 5th gear wide open for extended periods of time. The HS are slower and more technical. Right now I feel I need to drop the main and the pilot jet. My bike has no pickup in the mid range and I cannot get it to rev out. The plug is jet black and a little wet. Over the years I have always dropped the main 2 steps and the pilot 1 step at my elevation with all of my new 2-S bikes. But this is my first KTM and it is not jetted for sea level so my starting position is a little off.

Last night I found orange plastic shavings in my gas tank so I took took the carb off the bike and took off the float bowl. The main jet had a slight discoloration to it (rust), it had what looked like dirt in the float bowl and I dame near stripped out the pilot jet. The pilot jet felt like it had lock tight on it. I cleaned the carb and put it all back together and I will take it out this pm. The bike was setting on the showroom floor for over a year and I guess I should have expected that to happen.

I use MOTOREX POWER 2T @ 44:1:ride:

I am in the high desert with an evevation of 6400ft. with a current temp of 61 degrees. I race HS and desert events 80 percent of the time which vary between 6000-10000 feet and above with a temp of 80+ degrees. My first event however will be in two weeks at an elevation of 4200 ft and about 70 degrees. The desert events here are fast but not 5th gear wide open for extended periods of time. The HS are slower and more technical. Right now I feel I need to drop the main and the pilot jet. My bike has no pickup in the mid range and I cannot get it to rev out. The plug is jet black and a little wet. Over the years I have always dropped the main 2 steps and the pilot 1 step at my elevation with all of my new 2-S bikes. But this is my first KTM and it is not jetted for sea level so my starting position is a little off.

Last night I found orange plastic shavings in my gas tank so I took took the carb off the bike and took off the float bowl. The main jet had a slight discoloration to it (rust), it had what looked like dirt in the float bowl and I dame near stripped out the pilot jet. The pilot jet felt like it had lock tight on it. I cleaned the carb and put it all back together and I will take it out this pm. The bike was setting on the showroom floor for over a year and I guess I should have expected that to happen.

I use MOTOREX POWER 2T @ 44:1:ride:

I like to figure things out myself, so I usually get a needle most reccommend, get a couple of MJ's and a pilot or 2. I would look at one/both of the needles I mentioned, get a couple of jets incrementally smaller than what you have and work from there. You definitely need to lean it out. I would start with the needle.

If you are going to keep your needle and change only your jets, do a 3rd or 4th gear plug chop if you have the room to see where you are on the main. It really won't mean anything if you change needles. You could do it once you change out the needle.

Thanks for the info. I think I will stay with your advice and order some jets from my dealer. I ill play with the needle as time goes on.

Thanks for the info. I think I will stay with your advice and order some jets from my dealer. I ill play with the needle as time goes on.

You're welcome. I would start with the needle. I don't know of many that get the stock needles to work worth a hoot. Install it, ride it, and see where you are. It's an easier change as well.

You can proabably get one used off KTMtalk for next to nothing.

Where can you get an N3CH needle?

You can get the needle from a KTM dealer. I think it's the stock needle for the 2003 250sx. They work very well in the 300 and as noted much cheaper that the JD kit.

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