Hey so I am new to the website but I have a question I bought a 400ex it's a 1999 I was told and it has a 440kit eldebrock carb big gun exhaust kn air filter and I believe that is all that is done to the engine the lady I bought it from said that she bought it from a guy that did all the work and the bike has lots more bolt on extras also but the way the carb is set up it doesn't have a choke an wont idle is there anything I can do to make it idle and possibly give it a choke it will idle for a second or two then shut off and it really annoying plus it can be hard to start also so any tips or tricks to know with all the work it has done to it I should know

 

A quick search relieved that those carbs are really not liked. Sounds like a race carb where you don't sit their and idle. I would put a factory carb back on and get rid of that one.

 

^^^^ I agree here. But are you sure that a choke cannot be added? Just makes no sense to me that any ATV carb would not have a choke installed, or a place on the carb to install one. Does the carb have an accellerator pump? If so, push the throttle a few times ( squirts of fuel ) and see if it starts....the pump can work as a primer.

 

If it's a Edelbrock Quicksilver or similar to what came out on the 97/98 Ktm 620s then it is junk! Couldn't adjust them worth a flip. To adjust the main jetting you pulled the top cap cover and turned the screw to adjust main jet size..None of us techs could get one dialed in good enough to where they would idle good and accelerate at the same time. They finally got rid of those and went to a Mikuni in 99.Throw it away and get a Mikuni or FCR. Plus I've heard that Edelbrock is out of the cycle and atv carb business..

 

Ok thanks I am getting into racing so I might hold onto the carb then but is there anything I could do to make it idle at all like jetting or anything like that

 

Also I can't let off the gas or it will die so I constantly am on the throttle a little bit at least

 

The jetting is by the way of metering jets and also the needle sizes determine themselves how large the main jet flow is by how many "clicks in or out" they were adjusted to. Confusing as all get out and way too many combinations to choose from. When they came out supposedly the big bore kits and carbs were supposedly calibrated to each other..That's the problem,supposedly.. Metering jets are still available in numerous sizes along with needles,but I couldn't even start to advise you on what to use if you changed what's in the carb already. Only thing you can do is try adjusting the needle while it's idling or at least trying to idle. Click in or out a couple positions and see if it can idle and accelerate better. Remember where you started from!! Here's a sample of the metering jets and needles still available.edelbrock quicksilver metering jets | eBay
edelbrock quicksilver needles | eBay If you get tired of fooling with it,plenty of good used Mikuni and Keihin carbs on ebay that would work.
Even this old Ktm LC4 620 with its erratic idle is what a new one sounded like straight out of the crate if you we lucky and didn't have to start adjusting.

Plus here's an old post I found on a Harley forum that people were talking about the Edelbrock carb and it's problems.

"KTM (Austrian dirt bike mfg), used the QS's, (36 and 38mm) on their '97 and '98 400 and 620 4 stroke singles because that's the onlt carb they could get at the time to meet USA smog laws. I suspect the ones used on the H-D's are similar in that they do not have a standard PJ and MJ, but just operates off the adjustable needle. They originally came out w/o and accel pump and it was vented internally. In stock form, they just didn't run real well and were difficult to start. Edlebrock offered a accel pump and an external vent upgrade and this helped them quite a bit. I spent days working with these carbs on three different KTM 620's and could only get them to run reasonably well. With only the AP and the needle to work with, it seemed you could get it to run pretty good in the low to midrange, then it would fall on it's face on top, or you could get it to run reasonable well in the mid to top, and it wouldn't run well on the bottom. I had three different needles to work with too. Most everyone who had one on their bike replaced it with a Mik BST of the Keihin FCR and the bikes ran 100% better. Maybe the new ones can be made to run well, but I think the design of the carb compromises it to some degree compared to other carbs out there. I've still got three of them in the garage I use for paperweights"