need some help!!!!

[ex_freestyle]

o.k. i need some help and advice on the good old 400ex, about a month ago i decided to rejet my quad cause it was sputtering in the top end no big deal right. i went 4th clip from the top and it ran a bit better than it did at first it then it got just a bit colder out and it started to run like smurf once again and then i parked it in my shed for the night and evrey time i want to go for a ride i had to use the trusty jumper cables to start my beast, and i also put it on the charger for the night once and a while. i went from a 165 main all the way up to a 175 and back down again and its sitting at a 165 right now and it sputters in the top end once again. but today me and my buddy went for a ride on the lake and we were sucking doughnuts and all that good stuff i let my quad almost hit the limmiter trying to out roost my buddys z-400 sure enough i did but when i came out of the corner my quad came to a complete bog out and it slid to a stop. i sat trying to fire it up until the battery went dead which took about 5 min. the tank is still half full, my buddy had to tow me home sad to say. once i got home i decided to take apart my quad first checking the wiring all is good, then i took apart my carb and cleaned it out and put the needle back to the 3rd clip from the top and jetted it to a 170, i checked my grounds and they are also good, i get a spark out of it and fresh fuel sitting in the tank and i even dumped my oil just for the sake of it and my spark plug is a nice golden brown also. what have i missed, i have spark fuel and air and still no go and i havent seized it up either it still can turn over just not fire. please help me im getting more fusterated by the min. thanks

[interceptorz28]

I am just gonna throw this out there. Maybe you did actually foul the plug because your jetting was to high. Try a different plug. This is just a guess.

[hornetgod13]

If your airbox lid is still on than your quad is too Rich. Go down from a 165 not up. As was already mentioned it's a fair bet that your spark plug is fouled. Swap out the plug. When you pull the old spark plug check the color. If it's black your set up is too rich. If it's white than you're too lean. Light brown or tan mean you're dead on.

[Honda#4]

Yea if you have your lid on your wayy!! rich take it out and with the 165 main you have in right now it should run perfect. And put in another plug.

[ex_freestyle]

ya i already have my air box lid off when it started to act up

[Honda#4]

try a 170 main then see if that helps.