I just bought a new 400ex. It is really hard to start in the cold weather. Does anyone have any tip, tricks, or ideas. I would really appreciate your help.

Thanks

 

two words: SPARK PLUG!!!!! me and my bro file or clean our plugs if the ex's are hard to start and after the cleaning, it fires up on ONE try.....
to avoid the plugs, just warm your quad up like in your garage with a heater or try not to put to much gas to the bike and have patience! hope this helped....but a good spark plug, CLEAN, will do the trick!

 

Try three pumps on the throttle, full choke, hit the starter and barely crack the throttle to help it start then try three quarter choke below 30 degrees mine requires full choke for 10 seconds then the first detent or 3/4 choke works great. Also use stock spark box. White Bros box causes cold start problems.

 

I OWN A 300EX AND I JUST GO OUT IN THE MORNING AND PUMP THE THROTTLE 2 OR 3 TIMES AND THEN HIT THE START BUTTON. I DON'T USE CHOKE AT ALL. IF IT DOESN'T FIRE UP REPEAT THE STEPS AGAIN. DON'T PRESS THE GAS WHILE ITS RUNNING (JUST STARTED)OR IT WILL DIE. KEEP DOIN THIS UNTILL IT STARTS UP. DON'T BE DUMB LIKE ME AND FORGET TO TURN THE GAS ON SOMETIMES OR IT WORK!

 

i had the same problem last year, tried everything even new plugs but that got costly after awhile, not alot but also got tired of running to the dealer, anyway i sat my EX beside my woodstove in the garage for 15 min to 1/2hr and it started right up not one problem, also used a gas heater a couiple times

 

I still have the same plug in my 400 because it is to hard to change. But, do change your piolet jet from a 38 to a 40 or maybe a 42. Also you will need to learn the correct starting rutine for each quad. I have just found out mine for cold weather is to chock about 1/2 way and pump the throutle 1 or 2 times and then push the start buttom. Do this about 3 or 4 timesand then as I push the start button work the trottle some. Mine then startes. This might work for you. But also make sure that the airscrew is adjusted correctly and this will help.

 

two words: SPARK PLUG!!!!! me and my bro file or clean our plugs if the ex's are hard to start and after the cleaning, it fires up on ONE try.....
to avoid the plugs, just warm your quad up like in your garage with a heater or try not to put to much gas to the bike and have patience! hope this helped....but a good spark plug, CLEAN, will do the trick!