Cold weather/Carb...

[Mike594]

So I've read alot of other forums and boards, and apparently the 400's have a real issue with starting in cold weather. My problem though is that it just never stays Idling. I'll give the throttle a few pushes, start it, and it sputters. Two pushes, start, sputters a little longer. One push, sputters, idles for 5 seconds. One push, yada yada yada. It seems like the most it will idle is like 10-30 seconds, then it craps out. Unless I hold it at about 2000 rpm, but do I really have to hold it @ 2k for 5 minutes just to get this thing to warm up??? This is was in a barn too, by the way, where the temp was about 30, which isnt TOO cold. Im new to this quad, and im not really sure where the idle screw is on the carb, nor do I know exactly how I should be choking it. Can anyone please help me with this??? Maybe I should change the plug and clean the carb too??? Where is the idle screw at?

Sorry for sounding like an idiot, but any help would be greatly appreciated. Thanks guys! :)

[rob_990]

its normal for it not to be able to idle for like 5 min. just give it enough gas so itll say running till its warmed up. i wouldnt mess with the idle to much if it idled good in warmer weather and if it can idle after 5-10 min. of running. but if it still cant idle the screw is located right next to the choke. its sticking out and you can adjust it with your fingers.i normally just have my chok on for about 30 sec or until it wont die without it.

[Mike594]

Well I don't know how it idles in warm weather or how it runs in warm weather, as I only bought it last week.

[Newrider08]

I have the same issue with my 2002 400EX and I have been told to rejet the pilot to a 42

Here is the article I was referred to

http://www.atvriders.com/articles/pilotjet.html

[Mike594]

Did you rejet? And if so, how is it running now?

[Newrider08]

Runs good, starts right up even though its 18 degrees outside. I give the throttle a couple of pumps and it starts and idles without even using the throttle most of the time.

I may end up going with a 40 pilot jet and just leave it in year round because I think the 42 may be a bit rich during the summer so in my twisted mind I figured the 40 would be a good in between that I could use year round

[Mike594]

Did you change the main jet or anything else? Or did you just intstall the pilot jet and that was it?

[Newrider08]

I just installed the pilot jet, I have not noticed any stalling or under power problems so it worked fine

[Mike594]

Alright cool, thanks alot. :)