New WR400 owner. 1998 with starting issue

Just bought a pretty clean 98 for $1000. In it's history supposedly has had a rebuild. New bars are on WITHOUT decomp lever? I looked around on head & think I found the valve...but yes it has no cable & lever. When the auto-decomp valves are installed does the manual decomp junk on head stay? I'm just not sure it has the auto-comp. And....I can't get it running :/

This must have a "hotcam" in it cause I got it running today! Foul plug & old gas was all it was. Was about to pull carb but she fired so I'm running seafoam through some high test. NGK CR8EK is what I put in. Stoked! Non virused work manual online? Links?


I'm looking at the threads on the "eddy" mod & I'm puzzled. As far as I can see the metal part moves left. The plastic lever thing moves right. Wiring together? If my plastic lever was to go LEFT...well it couldn't, it seems like what it's attached to is bottomed out inside carb.


Also am figuring this ^^^ is my throttle stop. Things on this carb seem to be in different order than the "how to mod" documented bikes


Previous owner sure spent on the farkles!

The plastic arm is meant to go left with the metal arm.

The spring should be putting tension on the plastic arm to hold it against the metal arm(attached to throttle).

As you turn throttle the plastic arm pushes down on the plunger which has a rubber diaphragm hidden down below. It squirts fuel up through the carb out a small nozzle directly into the cylinder. It's called the accelerator pump. You need to take carb off and look through from the air box end and watch to see if fuel squirts when you turn the throttle.

Usually people put an o-ring around both arms to make sure the full squirt happens.

As for the throttle stop. Leave it until you get the jetting correct. Unless you are an A class rider you won't need to mess with it.

My 400 was insanely powerful with just good jetting and a good exhaust.

See that's where it's wonky. The plastic arm & it's attached plunger is already bottomed out & can only be pulled UP or OUT of diaphragm area. I'll tear into it this weekend if I have time thanks!

Yeah. I can see it is all the way up.

Looks like it has been lifted too far and is jammed on the side instead of sliding back down.

After you pull it apart and clean it. All should be good to go.

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