hard starting 400

[jlowery78]

I own a 99 honda 400ex with a dyno jet kit in it, and a 42 pilot jet. I also have removed the choke in carb. Installed an HMF pipe and a k&n filter. Running without air box lid. This thing is ridicously hard to start when cold. Once warmed up it runs like a raped ape. Would increasing the pilot jet help out starting it when it's cold? Someone also told me if the intake valves are set a little on the tight side would cause this problem. If my sparkplug is fouled, I know it would be hard to start, but would it run good once warmed up? Thanks.

[hard one]

You need a choke dude!

Almost all ex's are hard to start even my 300ex.

I couldnt see how you could get it running with out it .

my 300 wont start with out the choke

TRY PUTTING IT BACK ON


Hard One

[BLEEDRED]

I keep a battery tender on mine to make sure it's got good juice. Starts all year, even if it's below zero. 42 pilot seems like it would be fine. That is what I have.

[stc416rider]

uu prob need a choke i was thinkin of takin mine off but i wouldnt be able to start it so i decided not to

[h400exrydr]

when i puta 42 pilot and a 155 main in the EX in my sig it would start up right away with no choke. all i had to do was pump the throttle 2 times and she would fire almmost instantly. then i would have to jus hold the throttle so it was just above idle till it warmed up.

[Crazy Diamond]

Gotta have the choke! Was it being there causing a problem???

[jlowery78]

It sure was causing a problem, restricting AIRFLOW. I rode a friend of mines 400 ex with the choke removed from carb and WOW, instant throttle responce. So I had to do it to mine. I to pump the throttle 2 times before starting. Im going to try a new plug in it and see if it helps. I might buy a 43 pilot jet and see if that helps any.

[LightningEX]

I'll let you know how my 42 pilot works when install it if you still havent decided to get it or not.We've been havin nice below 0 weather lately to test it in up here in upstate NY.

[Dupontster]

If it doesnt have a choke it will still be fine. Mine has the choke removed and I dont have a bit of trouble starting it when it is cold out. Just pump the throttle 3 times then start it. You should have no problem if it is jetted correctly.