Won't Start

[ohsobad_chevy]

I have a 2004 400ex. It wasnt wanting to start so last weekend, I took off the air filter and cleaned it and re-oiled it, I replaced the spark plug, and blew a little carb cleaner through the carb. I put it all back together and it fired right up and ran great. It sat in the garage all week, while i was at college. I went to fire it up this weekend, and the @#$@# thing would not start. I have tried everything that i know to do. I ran down the battery trying to get it started, so i am now charging the battery. It seems like everytime i get it running good and ride for a day, when i go to ride it the next time it wont start. I have changed the jetting, due to the HMF pipe and UNI filter. I have had several mechanics check to make sure the jetting is good, and all of them said it is perfect. I dont know what else to try, so any input is very very helpful.

Thanks,

[wboy62417]

Check your kill switch and make sure it isnt grounded to your handlebars a friend of mine had a cr 125 that wouldnt start so he sold it to one of my other friends and come to find out the kill switch was grounded out to the bars he took it off and it fired right up the first kick

[ZSK]

What is your jetting at? Are you running an aftermarket CDI? Do you have the stock battery still?

[m1ke]

FUEL ON / KILL SWITCH IN RUN POSITION? pull plug check for spark by touching the tip of the plug against the engine and turning starter. if the spark is not consistant or visible.............................coil or wiring problem.

[ohsobad_chevy]

I am currently at a 152 main and a 42 pilot. I know it is not the jetting though, because it has ran fine with the same set up many times. Ive done plug checks as well. Other than that, what is a CDI? and yes i have the stock battery.

Thanks,

[ZSK]

A CDI is commonly known as a rev box. The most basic ones just increase your RPM limit by 1000 RPM's by utilizing an ignition curve from an XR250. The good ones, provide a different ignition curve also. You need a fully charged battery to even think about starting the cheapies.

I suggest the jetting even if you think it's right. On my stocker, the only difference being a K&N filter with no lid, I'm running 2.5 turns and a 42 pilot. I really suggest going to a 45 to help starting. I use the choke and hit the button and it starts up after sitting for 2 weeks. Each quad is different.

[ohsobad_chevy]

I will put a 45 pilot in and see what that does. By the way, It is getting a good spark.
I am out of reasons why the @#$@# thing won't start. It has me beet.....