Are most of us STILL fouling plugs?

Gary: I also experienced a very pronounced and annoying exhaust popping when decellerating. I found the culprit to be an air leak at the intake manifold/cylinder head juncture. The manifold has a bushing insert mount that allows the manifold to slide over the Allen bolts and leave a gap there and the engine sucks in dirty air causing the lean condition and popping. I used a washer big enough to overlap the bushing and onto the manifold and it now holds it tight against the head. I have absolutely no popping now and the engine braking is more pronounced. Curing this air leak also allowed me to get the jetting spot on. It carburates perfectly now.

[This message has been edited by Boit (edited 11-01-2000).]

[This message has been edited by Boit (edited 11-01-2000).]

I love the EKP on my '00 WR timed bike.

PJ 45 at 1 turn,

EKP #3,

MJ 185,

w/Up-Tite pipe and 14 SuperTrapp discs.

This set up works very well (screams) for me in the desert.

880 miles on the original plug.

It appears that some of you are close to this set up except for the main.

Just more info for everyone, good luck!


I have worked with George Earl in the past and developed a couple of Four stroke pipes (95 KTM 400 and a 97 ATK 605) Georges Uptite pipe is probably the highest horsepower generating pipe for this bike and it is a top end high RPM power generator (really loud pipe). Running 14 disks and riding on the top of the RPM range I can see how you would need a larger Main jet but a 185 with a E tapered needle still sounds big to me.



Seriously?!?!? I hadn't even thought to look! I'll check tonite. 99 WR or a 00 WR - not that it makes any difference.


'00 WR - a big BLUE thumper w/all sorts of fun modifications.


What altitude are you riding at. I'm at 5,000 ft here in New Mexico. Your jetting sounds very close to mine, with the exception of the MJ. I run a DSP pipe and I'm starting with a MJ=165. I figure I'll probably end up with a 168/170 once I get the low speed circuit cleaned up.


'00 WR - a big BLUE thumper w/all sorts of fun modifications.


I think you're right about George's pipe, I'm running the header too, with 15/48 gearing. This pipe is probably too loud for anywhere but the desert. I don't think I could get away with it at Kennedy Meadows or even Gorman.

MJ 175 fell flat, 180 ran good. I bumped to 185 to see what the boudaries were, no real difference from 180. Still undecided on those 2 choices.

Gary: Most of my riding is right around 3,000 ft, usually cool weather with this jetting.

All you woofters must not be riding hard enough!!! :D:D:D

I've NEVER fouled a plug on the beast! :)

Try going one range hotter (lower number) if you keep fouling them.. either that or get someone who knows exactly what they're doing with the jetting to sort it out! :D



**Ride it like you Stole it!**

Matt Porritt

99 YZ400F

Vist the Rubber Chicken Racing Online Shop

Discounts for ThumperTalk members.

in all the time i've been telling them to try a lower plug, you're only the second person who has said it.

do they listen, do they try it!!!

you can take a horse to water......


Yes the fouled plug problem is solved! I did not have to go to a hotter plug. And Matt I DO ride quite hard the banged up plastic and constantly buying rear tires proves it!!! Read my new post GOOD NEWS/ BAD NEWS.

Same here never had a fouled plug. I didnt even take the plug out for six months. You 'girls' are just not riding hard enough.


what's going on here?

is there a gloat factor involved?

are you after a gloat award?

if a bloke says he's fouling a plug what is the point in saying 'i'm alright'?

we should recognise you boys for being the ace-o-lux mechanics you really are!

talk us through how you did it. was it the wonderful upbringing, the apple pie, getting laid at 14; was this the turning point? was it watching the 'indy 500' a third time that gave you the mechanical insight? do you have any lucky omens we could follow as a sign, for instance do you wear different coloured socks? is there anything we can do to follow you, as a sign of our devotion & worthiness?


Taffy ole boy, Was that directed towarads me? You are a cranky ole son of a bitch aren't you? Maybe you need to get laid. Well...if this makes you sleep better at night, here is my setup. 48 pj, 170 mj, fuel screw out 3/4 of a turn, DRS at #3 clip (waiting for DVP to come in) CR8E plug, elevation 3500-5000 ft. temp. 50-70 degrees. Entire airbox cover removed. Stock exhaust no baffel. By the way I'm flying in to London for Christmas. I can stop by and tuck you in at night if you want. Lighten up Taffy.

[This message has been edited by Kermit (edited 11-07-2000).]

172 main

48 pilot

1 3/4 turns, fuel screw

WB E-series, s bend 5 discs.

air box lid removed.

Close to sea level, premium unleaded

Never fouled a plug and doesn't back fire or pop.


Originally, there was a question asked: "Are most of us STILL fouling plugs?"

It looks to me that people are simply answering the question, not bragging.



99WR,WR timing,throttle stop removed,Uni filter,E-Series pipe,carbon air box,Pro Tapers,lights removed,YZ tank,13 tooth sprocket


god help london! i'll tell everyone you're coming. no, my comments weren't aimed at you at all! i haven't got the slightest interest in your settings.

i was taking the piss! we're both fluent-sadly at two different languages!

jetting-that's JD's area. i'm interested in the theory & not the effort. i'm cerainly not spending countless years setting up my carb.

my bike starts & runs 99% spot on. now yours is as well, leave it alone & RIDE IT!

i'm glad you got it sorted.


Well...Taffy sorry for busting your balls. I just took your rant wrong. You got to be hell funny in person. Ride on Taffy. Make ole blue proud!


You got a way with words, makes me smile :) , Starting to catch your drift more all the time.


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