Still not running right!

[MCF400EX]

Hey all,
Well, I just cleaned the carb on my 400 and its still not running right. It idles when the choke is on, but when I turn off the choke, the RPM's go up slightly and then it dies. Any ideas as to what could be causing this?


Matt

[UglyMotha™]

check all your vents and the gas tank vent :o

[MCF400EX]

By vents what do you mean? Where are these vents at that you speak of?

Matt

[UglyMotha™]

rubber lines on the carb and there's on the carb and the one on the gas tank cap trying take the cap off and see if it runs, if it'll only run when the choke is on it means your not getting enough gas or too much air

[MCF400EX]

Forgot to mention, also spits and backfires when throttle is applied. Could I be running too lean?

Matt

[UglyMotha™]

no........... sputters= rich bog=lean

[MCF400EX]

So I need more air and less fuel. Should I adjust the mixture screw at the bottom of the carb? Which way should I turn it to lean it out?

Matt

[UglyMotha™]

not necessarily, if it will only run on the choke than its not getting enough fuel, you won't be able to rev it up with the choked on cause the engine is choked


what started this problem why are you occuring it you need to pinpoint the problem first don't go adjusting crap if it ran fine before with the air screw where it's at then why would you have to change it have you added something to your bike or did it just up and stop running

[MCF400EX]

Its bone stock. I had it sitting for a while, put a new battery, spark plug on it, changed the oil, fired right up, just wouldn't idle. Cleaned the carb out, still won't idle.

Matt

[UglyMotha™]

then you have problems elsewhere DON'T ADJUST ANYTHING................... an air screw just doesn't up and adjust itself while its setting in a garage, furthermore it has very little to deal with this situation, your problem lies elsewhere, i would check the vents, air cleaner make sure you didn't get a mouse nest in there, also check the snorkle, put a new plug in it, your plug could just be fouled

[MCF400EX]

Just checked the snorkel and air box, no obstructions, vents seem to be free of clogs and the like. I'll try putting a new plug in it tomorrow and see if that helps. Don't have a big enough spark plug socket :rolleyes: so I'll have to get one from my neighbor tomorrow and see if thats the issue.

Matt