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skyline296
02-27-2011, 05:00 PM
So i've had my 03 ex jetted with a motoworks pipe for over a year now with no problems. In the winter i move down on my needle clip and in the summer i move up a clip.

This morning i start it, fires up and i ride for about 30 min. Got some grub (about 1 hr) and then it didn't want to start. We pull started it and it ran. Shut it off again about 15 minutes later, same thing, doesn't want to run. Now the strange thing is it usually starts up without any drama.

After dragging it behind my buddy's and pop starting some more, seems like its loaded up with fuel. It boggs to life and then runs fine. But if i let it sit for a few minutes it just doesn't want to restart.

I had thought maybe my float was stuck so i ripped my carb apart, everything seemed normal. Also moved my needle clip back to my summer setting just to see if it made any difference. Moving the needle caused my midrange to get lean (as expected), but no real changes otherwise. If i let it idle for about a minute it just stalls out and then won't restart, like it's getting loaded up with fuel. I put a new plug in it about 2 months ago and i'm totally stumped. Time for a carb rebuild or something?

honda400ex2003
02-27-2011, 05:07 PM
bad gas possibly?? huh i guess ill have to think about this one for a bit.

ive been hearing alot of issues with gasoline this winter from the sled guys...

a leak would make it lean...

clogged up filter would make it rich...

valves starting to get out of spec lash wise could possibly be letting too much gas in there...

carbon buildup on the exhaust surfaces could make it flow less making it run rich... (pretty odd though)

a jet loosened up inside there causing it to get too much gas... (did you check all of the jets or just check the float and the needle?)

clogged up spark arrestor could restrict flow enough to cause it to run rich possibly...

coil starting to get fried not allowing enough voltage to get to the plug...

cdi starting to go making it hard to start when it cools off...

im not sure on any of them thus the thought dots ... not trying to be smart here or anything. just thoughts coming to mind on possible things.
ill keep thinking it over a bit and see what i can come up with. it seems odd that it just started happening.
steve