Here is where I am on jetting, still need input

Had my bike out for the first time since I rejetted to the following ('99 WR400, YZ timed, all mods):

165 main

45 pilot

EKQ 3rd positon

Screw 1 turn out

Rode Rampart Range (6000 to 8500 ft) By the way CO riders, Rampart is totally open.

Bike started with choke only (remember I had to use the hot start after new jetting in the garage) but it would not stay idling after warming up. I already have the idle screw all the way in (slide up).

The bike would run, but everytime we stopped, it would idle fast for a few seconds then slow down and die. Hard to start but it eventually would. I went from 1 out on the screw to 1 1/2 and that seemed to help just a bit. I'm almost certain my slide is in correctly.

The top end felt like it was missing at the very high RPMs. Almost cutting out. Gray wire is cut.

There still is a delay with the twist of the thottle (still have to do the taffy mod but not sure if that is the problem). Bogs then catches.

Plus, I think I am going to have to bite the bullet and pay for a top end. It was making some weird noises and shaking quite considerably.

Any and all advice welcome. Thanks guys, Doug


i think the needle you got is the pants. sorry mate! i'll hold back next time, you know me :)

a 'Q' is too big. if you ride at altitude the EKN would have done nicely.

sounds like your slide may be upside down. otherwise you're meant to be very lean at low revs. have you still got tha\t 75PAJ in? if not, put it in!


OK, once and for all...the curved out part of the slide goes on the bottom right? That is how the microfiche shows it. The only other thing I can think of is the valve assembly(?) (the thing with rollers the slide goes on) is in backwards. But I have it in the way the fiche shows it.

I did notice that two diffs between the 99 and 00 400s.

1) The 99 has a curved out portion of the slide plate. The 00 does not.

2) The 99 valve assembly slopes to the slide plate and the 00 slopes away from the slide plate.

Is it possible the fiche is incorrect for the 99?

the slide plate goes on the engine side with the cutaway at the bottom so the '99 picture is good. check that you can hear the slide dropping back onto it's seat. oil things up.


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