Starting Problems

[tivoli410]

My '04 400ex just plain won't start sometimes. Usually it starts right up with the choke on and then runs great but everyonce in a while I'll have to pull start it around the neighborhood and then it starts fine everytime after that until it does it again.

When it's happening the battery is charged and the starter is trying to turn over just nothing ever catches. Every once in a while there is a backfire but if you keep trying to start it all that will happen is you'll run the battery down. Pull start it once and then your good to go for a week or so until it does it again.

Ideas? Thanks in advance to anyone who can offer up advice.

[Pappy]

install a 42 pilot jet, all my 400ex's have this same issue, the pilot jets is the cure:p

[hornetgod13]

Pappy hit the problem right on the nose. You need to bump your pilot jet up to a 40K or 42K. The 400EX is notorious for the cold starting blues. Since I've installed my 42K Pilot Jet I no longer even need to use the choke. I just pump the throttle a couple times and she fires right up.
www.jetsrus.com carries the different sized pilot jets. With some basic tools you can swap it out yourself. Search the websites "How to" section on step by step instructions on how to get it done. Good Luck :D

[tivoli410]

Awesome, thanks for the help guys!

I have my truck torn apart in the driveway right now so the four-wheeler will have to wait about a week. Glad to here it's not something worse. :D

[blasterandy]

Another cure that they didn't say is a fresh spark plug. You should always have a good spark plug. Thats they way mine is. Even after the 42k it will destroy spark plugs after about 20 or so cold starts:D