WR400 won't start w/choke when cold

I bought a new 2000 wr400 in April '01 and it won't start with the choke on when the bike is cold. Starts fine after it warms up.

This is an awesome bike and I know I'll love it once I can figure this out!


How exactly are you getting it started? Or did you mean it starts fine when it warms up outside?

If that's the case then you just need a little fuel screw adjustment or pilot jet change. First check the current position (number of turns out) of your fuel screw. Then try turning the fuel screw out at least a 1/2 turn to richen the idle mixture. Don't go more than 2.75 turns on the screw. Go up a size in pilot jet instead (very easy to change, just remove bolt at bottom of float bowl to access). It will also help to give 1 or 2 blips of the throttle when it is colder than normal outside. Once again, this will richen the idle mixture.

A little more detail would be helpful. What temps / elevation, starting drill, etc.


Steve T

[ January 13, 2002: Message edited by: skthom2320 ]

[ January 13, 2002: Message edited by: skthom2320 ]

[ January 13, 2002: Message edited by: skthom2320 ]

don't go up a PJ size!!!!!

go down one and adjust your idle and throttle response on the PS.

that's all you need to do. anyone can work it out surely? you don't need choke because it already runs rich!


Taffy is right, its already to rich. Here is and interesting test. Open your hot start and try to start the bike. You might be surprised.

It doesn't sound like you need to change a jet quite yet. First try and turn your fuel screw in 1/2 turn at a time.

Good Luck!

Mr T

Well, if Larry's starting it in cold temps.. My '01 WR426F required a couple twists of the grip before firing up when the temps dropped down below 45°F. I left the choke on for it to warm up a bit, and it was fine after that. While up to operating temp, it never required choke to re-start.

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now