Where to get an "E" needle?

I called SUDCO and they only stock the EFP and EMP needle. Anyone know where I can get the EKP? I tried my dealer to see if they could get a EJP from a YZ. What a joke. Same old sorry story... "It will be on back-order forever" they said. Anyway, would the EFP or EMP be a reasonable substitute if set to the appropriate clip position? Maybe the EMP with the clip in the #6 groove?

I ran into the same supply problem. I ordered an EKN from the local dealer, from HLSM, and from a dealer in OZ. The local dealer worked out to be the fastest, but I did get from Oz also - but it took a while to clear customs (cancelled the HLSM order). It took about three or four weeks to get them. If I thought Moose wasn't going to come looking for my spare.....I'd let you have it.


The EMP is a direct substitute for EKP by setting it 1 clip richer.

EMP#5 equals EKP#4, ignoring the small .9mm length difference at the tip.

I would suggest you get both EMP and EMN from Sudco. EMN for lower altitudes and cooler temp, EMP for higher altitude and warmer temp.

Since you're getting them from Sudco, get a pilot air screw & spring too with a #48 pilot jet. Set the air screw to 1 1/2 and pilot screw at 1 1/4 with the #48. Strap yourself onto the seat when you go for your first ride!! :)



Rcvd a e-mail from Sudco last week. The air screw is on backorder. I was not informed when (if?) they'd be in.

This will bolt up to my 99....right??


'99 WZ with all YZ mods, FMF PowerBomb header, Stroker SX-1 silencer, SS front brake line, forked over by Pro-Action, OEM YZ tank and IMS seat.

NH Kevin,

Yes, the air screw will fit your '99 FCR. It was designed originally for your version of the carb. It also works on the reconfigured '00 & '01 Yamaha 'exculsive' FCR. It's pretty cool that they machined in the cavity for an adjustable air screw even when it is not needed with a simpler pilot air jet.

These must come in and out of stock because I've purchased them on 2 occasions.

Sudco part #021-230 is air screw, #021-235 is the spring that secures it. Make sure they know you want the air screw and not the pilot screw.


James and Michael, thanks for the info. I did try to order the airscrew and spring, and indeed it was on backorder. Currently I'm using the 48 Pilot Jet, 100 Pilot Air Jet, 200 Main Air Jet, Stock Acc. Pump setting. I changed the exhaust cam to YZ spec and ditched the WR ignition for the Vortex unit. Anybody have any exhaust recommendations? Seems like most of the aftermarket stuff is just as loud as the stock un-corked system. I can't justify spending the money to have a system that is just as loud and maybe gain 1 or 2 HP. James, what Main Jet do you recommend? (168?)I usually ride at about 1000-3000ft. Thanks, Jason.


Try a #170 main jet first and evaluate the main only at full throttle. Probably best to start with EMP#5 (=EKP#4) and 1 (+/-.1) turns out on the pilot screw.


I just completed putting in

ekn needle on # 4 (bought when EKN was the needle to have)

45 pilot jet

175 main

200 main air jet

air screw set at 1 3/4

started without choke

2001 WR426 air box top removed and vortip from fineline

I have a stumble at 1/4 throttle

and a flat top..

However after a plug chop

the plug has a black sooty body with a clean grey electrode

any thoughts




The difference between the EKN & EKP is slight. The EKN is STILL the needle to have for many.

What is the temperature and altitude?

Try smaller main #170 and most likely turn the pilot screw out to 2 - 2 1/4 turns. Check the response and starting. If the low speed is too rich go back a little at a time on the pilot screw while checking response. **The pilot screw may end up less than the 1 3/4 you are at now, but most bikes are a little further out when using a #45 pilot.

BTW, you do mean the pilot screw on the bottom of the float bowl don't you?(you wrote air screw), out is richer on the pilot screw(opposite of an air screw).


[This message has been edited by James Dean (edited 04-12-2001).]


I'm at 1 1/2 out on the pilot screw. It's hard to start with choke on. It's also hard to start with choke off. It acts like it wants a mixture somewhere in between. This happens when air temp is around 60-70 degrees. When it's colder, it wants the choke and when it warmer (75-80) it does'nt want it. I'll try what you said (1 turn out) and let you know.



Be sure to use a slightly fast idle.

James, thanks for the tips. Good news, I just got the EMP and EMN needle along with the air screw and spring! Will be installing tonight and let you know on the results. Here's my baseline set-up:

EMP #5

170 Main Jet

48 Pilot Jet

Pilot Air Jet Screw and Spring 1 1/2 out

Pilot Screw (front of float bowl) 1 1/4 out

200 Main Air Jet

Can't wait to try it. My friend has been doggin me with his YZ 426. Should be no more of that walkin away from me in the midrange now.


Looking forward to hearing if your setup matches mine. :)



I got it together and went for a couple of rides. The upper-mid range is most improved. However, the top-end revs are quick to show, but lacking oomph! I tried the 168 and 170 MJ. It's still relatively cool and the 170 seems stronger. I still have a "stumble" at about 1/2-2/3 throttle. This occurs in any gear at steady rpm/throttle position. It just burbles/mises in that certain range. When I hammer on it or go for a fast ride, I don't even notice as the revs blow right past it. What do you think? I'm running with the EMP needle in the #5 groove. Should I try #6 or switch to the EMN needle?



Try a #172 main jet and REMOVE the main air jet #200. A second plan to get the burble reduced would be to try EMN#4.

How does it compare to your friend's YZ426?



I'll try the EMN #4 with the 170 MJ and the #200 MAJ removed. I have'nt had a chance to do side by side comparison with the YZ yet. My "seat of the pants" memory tells me mine is still slower. I'll let you know on the jetting results and subsequent drag race!



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