5th gear problem...help?

[AK400]

I have an 03 400ex and when i run it in 5th gear with about half throttle for maybe 30 seconds when on along road the engine starts to quit. (also happens when i pin it) I thought it might be wanting more air so i got a K&N filter and it is still doing it. Its almost like it gives out and it jerks me forward and i pull in the clutch and come to a stop and sometimes the engine is off. I have no idea what is going on. The bike works great on the track and in the pits, but i never really have it pinned for very long......

jetting?valves? Has anyone else had this problem?

[GOTFEAR]

try running it with your gas cap lose might be air locking your gas cap may be bad

[QuadManiac]

Three likely candidates:

1) Gas cap breather tube is blocked or twisted

2) Petcock valve or gas feed tube is restricted

3) Float is set too low

How long does it take to recover till you can pin it again without the stalling?

Good Luck!

[86 Quad R]

could deffinately be vapor locking or a clogged petcock assembly but the float level is "fixed" (non adjustable).

i worked on one this weekend that had the same symtoms. end up being a restricted(clogged) pet cock.

[ZJTurbo]

I hate to jack the threas but was wondering if the gas cap breather could be the culprit then why do people block the breather tubes off??

-Ben

[04blasterkid]

on my blaster i plugged the whole and it did not vapor lock, all the honda wheelers that I have seen vapor lock... not all of them do though?

[86 Quad R]

Originally posted by ZJTurbo
I hate to jack the threas but was wondering if the gas cap breather could be the culprit then why do people block the breather tubes off??

-Ben

because theyre idiots? :rolleyes:

seriously tho. i havent seen guys blocking off the vent tubes. are you referring to the aftermarket lil billet thingies that you see being put on some quads? if so those are vented. :cool: