450 xcw high idle

I just got back from my first ride of the year. i have a 2009 ktm 450 xcw. the bike is brand new ive only put on 4 hours and have done my first oil change. Ive noticed that the bike will kick up into a high idle while riding then will stay high even when i come to a stop. the only way to get it to kick down is by slowly letting out the clutch and bogging it, any ideas what causing this? maybe a jetting issue? the jetting is just how it came and everything is stock. When the bike is cold i have to kick start it, and that can take a while. It doesnt really like to start, once its warm the electric starter has enough jam to get it going and it starts fine. Also after how many hour should i get the valves set. I would check my manual but i left it out at my cabin.

I just picked up a 2011 EXC and it has the same issue, I believe its jetting, I was reading the manual, and it clearly says if you have to turn the idle screw out past 2 turns and it still doesnt bring the idle down, the it needs rejetted..

Mine will idle ok with the idle screw backed out all the way, but thats just a band aid for the jetting..

Here is a link I found on a 2010 EXC where they were re-jetting and a dyno run.

Quite often the sign of a clogged pilot jet. Sitting for a while, the deposits start forming. I usually soak all my brass in carb cleaner twice a year.

Good Luck,


I have a new 2009 exc with JD kit installed, FMF exhaust, pollution crap removed. I have put about 5 hrs on the bike and I am having the same issue. I took it back to the dealer right after they put the kit in and told them about the hanging idle, they wanted me to just put some fuel through the bike and hopefully unclog what ever is in there giving me grief. I am sure something is gummed up in the carb. If I turn the idle screw down it makes it better, but when the bike is cold when I start it I can't get it to idle. The first time you roll up to an intersection and the rpm's don't come down sure scares the crap out of you. Has anyone ever used any kind of fuel additive or carb cleaner in the gas?

MrHix is most likely right. There's probably something in there clogging an orifice creating a lean condition. Turning down your idle speed is just a bandaind in this case.

If you want, start simple. Use fresh gas and some techron or similar, and go ride the piss out of your bike (making sure you hit all your rpm's). Even tho the hanging rpm at idle is definitely the pilot jet, there could be some gumming or clogging also in the main jet......so ride ride and ride some more.

You could also loosen the carb clamps, rotate the carb, and remove the float bowl or just the plug and spray some cleaner in there. While you're in there, you could go an extra step and remove and clean the jets........or replace them if you'd like.

Good luck.

Mine did the exactly same thing when it was new. I installed a R&D remote fuel screw so I could easily tweek it on the fly. Once the engine hit about 20 hours along with careful adjustment of the fuel screw and idle, it calmed down. It now has 60 hours on the engine and there is no hint of the original problem.

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