2004 xr400 only runs when carb is choked

[flyin3d]

Hi guys,

I have had this bike since new. It has not been riden in the past two years. Had to de-varnish the carb. I cleaned the needles, replaced the float valve and spark plug. The bike idles and runs perfect when the carb is choked. As soon as I open the choke, it starts to afterfire and die out. Anybody have any ideas?

Thanks

[matt10]

hi mate have u tried changing the jetting on the bike?

[creeky]

Recheck the pilot jet, the slightest clog will cause the symptoms you describe.

[ryanrodfl6363lu]

first mos important question is how could you let a nike like that set for over 2 years!!! LOL

mine did the same thing when i pulled the carb to clean it... i found that i had torn the O ring between the head and the carb boot (intake)... it was air leaking bad. check there as well.

[Trailryder42]

When you say you cleaned the needles does that include removing the fuel screw and cleaning out that passage? If you did that, make sure you got it put back together right. Order on the screw should be spring first, then washer, then O ring.

Since you've had the bike since new surely you know all the way down on the choke lever is off and up is on.

[creeky]

i found that i had torn the O ring between the head and the carb boot (intake)... it was air leaking bad. .

Good point, this is something that I had just about forgotten. In past years, I have come across two instances on XR400s that had the same problem, O-ring not sealing between carb adapter and cyl. head.

[ryanrodfl6363lu]

the o ring that goes on this intake part i was able to find at a local ace hardware. im sure that other hardware stores will carry them... funny thing is OEM sells them for a little over 5 bucks and i picked up 2 or 3 for .69 a piece! now im sure that they arent EXACTLY the same size, but ive had no trouble out of mine!

[michaelxr]

Hi guys,

I have had this bike since new. It has not been riden in the past two years. Had to de-varnish the carb. I cleaned the needles, replaced the float valve and spark plug. The bike idles and runs perfect when the carb is choked. As soon as I open the choke, it starts to afterfire and die out. Anybody have any ideas?

Thanks

Mine did the exact same thing after I removed the carb and cleaned it out. Check the float level. I adjusted my float level to be in spec after the tang pushed the little needle in. It did exactly what you say, ran find with choke on, but died out with choke off. You have to adjust the choke level to be in spec as it just touches the little spring loaded pin in the float needle.

[DarinBell]

This may seem silly but are you sure you your not getting the choke lever mixed up? I had a similar problem and realized that I was actually choking the bike when I thought I was turning the choke off and could never figure out why it wouldn't stay running.

[Hivoltage]

This may seem silly but are you sure you your not getting the choke lever mixed up? I had a similar problem and realized that I was actually choking the bike when I thought I was turning the choke off and could never figure out why it wouldn't stay running.

DITTO!