Ltz400 03 model help
 

Hi guys, I have had an issue since day one on this quad, can't seem to get it to idle for over a few min before it quits. If I higher the idle it will run but don't like it. Here is what I have done so far, dynojet kit, cleaned out stuck choke, it starts cold now just fine, after it warms up it dies. I swapped out the petcock for a raptor model as it just kept flowing gas in any position. Replaced float needle and seat as it was flowing fuel with float closed. I do notice that when I place my finger over the vacuum tube that is open along side the air inlet tube it revs up, I didn't think that sucked that much air as it's open to any debris dirt that may enter. Checked for vacuum leaks and to my knowledge non are present. It's just a strange thing.... But thought maybe someone has had the same issue. Fan comes on and I notice the engine idles lower as well. Idling issue was present before I touched it, just thought the kit would fix it.

Any help would be greatly appreciated, just bought this quad a couple a months ago and haven't really got to ride it since.

Bump - maybe all you techs are out riding yours machines. Hopefully someone can chime in the next few days.

If you are not using the vac tube it has to be blanked off. If you have re-set the carb to suit it with the tube open, you will have to set it up again. Some machines do tend to cut out after idling a while, I put it down to wear in the carb, but why leave an engine ticking over? It is just getting hot and using fuel.

Yes I have the vacuum plugged on the carb. Yes I have done the jetting per dynojet instructions. What do you mean by leaving ticking? I have had many quads over the last 15 years but purchased new, this is the first used one I have purchased and beginning to realize why the new purchases are better..... I have had this model before but not the problem. I just don't know why after it warms up it won't idle.... I cleaned out the pilot jet as well. Now that I think about it, I may pull the air mixture screw out and make sure that is clear as well.

Ticking over must be a UK term it is to leave idling. I never alter carbs etc, from stock, the makers spend a lot of time getting each model "right." How much time and manpower can a firm like dynojet, who make tuning parts for upteen makes and models, spend on each one?

Every bike, quad or side by side owner that I know of never drive a stock carb. All ways mod the air box and aftermarket pipe, gets you more power than stock. All stock machines run rich as it is from factory. I have owned many over the past 17 years and never had a problem jetting one. This may just be as simple as a valve adjustment as I am reading but will have to check into that soon.

Just completed the valve adjustment yesterday and still running the same. starts up cold but when warms up wont stay running and hard starting.... Anybody have this same issue?