I live in Quebec, Canada and on winter we see alot of -10 to -20 degre faraneith and yes, the 400ex will start. Do not forget to start full choke, pull 5 to 8 time on gaz and maintain it for 1 or two mininute and then after 5 minute of run, you can release your thumb of the gaz. The 400ex is a freezing atv, but can start on cold weather.

 

my buddy has a 400ex and it was a bear to start too. I live in northern PA and it's freezing up here. He put in a splitfire spark plug and has no problems since. I highly recommend the splitfire.

 

Maddog:


If you take the spark plug wrench in the tool pack, and grind a bit off of the outside square sides (round them out a tad) it will fit fine.


Also, changing the pilot jet to a 42, or a 45, seems to cure the cold start problem. Mine starts fine, but that seems to be the cure on another forum that is dedicated to EXs.

 

Yes my 400ex is a bear to start below 60 F. Choke it fully when it starts move it to half-choke and stay on the thumb throttle for a couple of minutes.

 

Yes the 400EX is a cold blooded son of a gun. But I wouldn't trade it. I did put the splitfire plug in and it has been considerably better. I am doing some homework on the Edelbrock Qwiksilver Carb and it said the the Edelbrock virtually eliminates hard cold starts on the 400EX. The only problem is the $450 price tag. I'm going to get it.

 

When I bought mine the dealer said it would be cold blooded for the first year or so, then when it got a little older, it wouldn't have that problem. Is this true?

 

i just found out what a pain up the butt they can be to start in the winter. after a good 5 minutes of cranking, it wont even come to life at all!
geez..

 

Reading all this makes me realize how blessed we Z400 owners are.

 

C'mon boys...a 400ex isn't that hard to start. The carb comes lean as he!! from the factory. Replace the pilot jet with a 42 ,and you'll never have to turn the choke on or have a tough time starting it again. There have been plenty of discussions on here about this. You also want to keep the battery on a trickle charger if letting it sit for more than a month. I use the Battery Tender, and never have a problem starting my quad. I ride in the mountains and the snow this time of year, and I've never been let down yet.

 

wtf? mine will not start no matter what i try! i dont have the tool that comes with the ex to remove the plug, and i dont have the right size socket, so i cant even get the freaking plug out!!!
why the heck is the plug so hard to get to?