only runs on choke

[ddtt145]

i just bought a 01 400ex and it will only run when the choke is on and it fouls plugs alot. it has a full exhaust and i was wondering if i just need to change the jets...any help would be greatly apreciated...thanks

[ddtt145]

somebody please help!!!!!!!!!

[Pappy]

being that this 400 is new to you, id suggest the following....


1) clean the air filter

2) check for any cracks in the air boot and make sure it is secure to the carb and intake

3) pull the carb and see what jet is in there and also it may need a good cleaning (old gas can be the death of someone, does it smell funny? lol)

4) usually needing the choke on shows a lean condition (needs more fuel or less air etc)

[bsent]

i have an 2001 400ex that did the same thing. it was the valve on the tank that was starving the carb of gas. it is worth checking before you start taking stuff apart.

[underpowered]

my money is on the pilot jet. running only on choke is usually a sign the pilot jet is clogged up. needs a good cleaning, possibly a new pilot jet. but no matter what, the carb pretty much has to come off and be cleaned.

[bsent]

i have an 2001 400ex that did the same thing. it was the valve on the tank that was starving the carb of gas. it is worth checking before you start taking stuff apart.