Serious Engine Problem..HELP!

[pork917]

Maybe im exagerating but heres what happened. Have an 05 400ex. After filling up my tank, i shut the fuel to off so we could piggyback our quads without the gas leaking. Once we got to the trail and I put my gas back ON I tried to start it up. It kept backfiring and dying out, and this was when I was starting it. It did this for like 15 minutes until the battery finally died. I jumped the battery and just had to start it and push the throttle all the way for like 5 minutes until it stopped backfiring and ran fine the rest of the day. Can anyone explain to me WTF happened? And after I finally got it to work my full tank was emptied out. I checked the airbox and it didnt leak into there or anything, I really dont know what happened, could it have been from piggybacking the quads? They sat like that for the hour and a half ride, and it only happened to mine. Thanks!

PS: If you guys could hook me up with a good site to get the best price for a K&N with Outerwears id appreciate it too!

[nakomis0]

a 'Serious Engine problem' aye?

Its probably from piggy backing it. I wouldnt worry aboput it if everything is fine now.

[TC426EX]

Yeah, probably just from haulin it there like that man. Probably just needed to jam on the throttle for a minute or 2 to refill the float bowl in the carb and get it primed. Long as it runs good now I wouldnt worry about it. '

As far as a good place to get the K+N and outerwear, I would check with C+D first (site sponsor with good prices, plus you get 10% off for being a member here), or Rocky Mountain ATV.

[pork917]

but what would explain losing a tank of gas?

[400exredrider]

the overflow line on the carb points to the swing arm of the carb, maybe your valve wasnt working well or you didnt get it all the way turnt off, they have a tendency to leak a bit