00 wr 400 jetting

4 replies to this topic
  • Guest_Guest_*

Posted February 18, 2000 - 05:52 AM


Still having jetting problems. When the throttle is whacked open from low rpm the bike has a major stumble and almost dies unless you back off slightly. Exhaust and intake restrictions have bee removed. Can the needle clip position be changed with the carb still on the bike? I had major problems yesterday trying to access the pilot jet due to the plastic spacer that surrounds the jets. Does this need to be removed for this task? Is the pilot jet inline with the main and the pilot screw off to one side?



  • Clark_Mason

Posted February 18, 2000 - 08:20 PM



On the 99 WR the plastic spacer/guide just sildes off by pulling it back and down. But be sure to note how it comes off so you can get it back on. You will be looking up at three jets the main jet the start jet and the pilot jet. I can't remember which is which between the start and pilot so take one out an read the size and refer to the manual should be able to figure it out.

As to the needle on the 99 WR on the R side I take off the dust protective cover then loosen the throttle cables from thier holding guide by the carb so they hang down. Then on the L side loosen the front and rear clamps holding the carb and then rotate it toward the left side and I can remove the top and get to the needle. Don't know for sure how the 00 WR carb is I know its a little different and slightly smaller so should be easier to work on.


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  • John_in_Long_Beach

Posted February 18, 2000 - 09:22 PM



I took delivery of my bike (2000 model) about 50 days ago.

The first problem I had was with the idle being too high and not backing down. Screwing out the pilot screw solved this. The dealership said they screwed it out 3 - 3.5 turns.

To me this is an indication that the stock pilot jet should be a 45 and not a 42, way too lean. But I never really had much opportunity to confirm this because I went right the a DSP pipe/header and a 48 pilot jet.

So two suggestions are screw out the pilot screw or just go to a 45 pilot jet. Then maybe the standard two turns out will work.

As for the changing these items. I don't take off the carb I just loosen the boots (air cleaner and intake sides) and pull it back a little and rotate it so that the front left screw (on the bottom cover) is not in the way of the cam chain tensioner.

As for the location of the pilot jet it is right in front of the main jet. But not visible. I bought a little tool from the dealership that is for adjusting the pilot screw. It is a small screwdriver with a little quarter size diameter wheel around it. This tool is also ideal for removing the pilot jet.

Best of luck. I hope that helps.


[This message has been edited by John in Long Beach (edited 02-18-2000).]

  • mcarp

Posted February 23, 2000 - 08:41 PM


It doesn't look like it would be easy to get the top cover of the 00 carb with the carb still on the bike. It looks like there are two screws holding the cover on (seems like there should be more) and one looks real hard to get to, and even harder to reinstall. If anyone has done this, please post how.

The pilot screw can be accessed without pulling off the plastic guard. Just let it drop onto a rag once unscrewed. yes, it is dirrectly in front (engine side) of the main jet.

Good news, at least the new throttle stop removal was easier than what it sounded like on the earlier models. At least that was my experience. I haven't reinstalled it yet, but it doesn't look too bad.

Actually this carb isn't so bad to work on, I had to remove the rear subframe and airbox on my last bike to get to the carb.

'00 WR400
'84 Nighthawk S

  • Airman11783

Posted November 21, 2005 - 10:33 AM


Can some one please tell me how to deoctopus my carb on my 00 WR400f


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