Check out my plug chop

Questions and Answers about the best carb and Head mods available for the KDX.
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strider80
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Check out my plug chop

Post by strider80 »

Sorry for the butchered lathe job, the steel is so soft the cutoff tool dug in and pulled it out of the chuck.

This was yesterday, ~1500ft , 53degF, slight uphill on pavement, 6th gear pinned for 5 seconds (it was a bit exciting).
2000 KDX200
Mods:
RB carb and head mod, CEK #3, 152 main, 40 pilot
FMF rev, TCII, Boysen power reeds, FRP torque spacer, modded airbox lid, Interceptor @ 40:1, 92 pump gas

So what do you guys think?
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Last edited by strider80 on 10:39 pm May 21 2007, edited 2 times in total.
2005 KTM 250EXC
2000 KDX200 (gone)
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KDXer
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Post by KDXer »

Looks very good to me. Not too rich and not too lean, 'bout perfect I reckon.

Compliments to Skipro for the pics and comments.
I put up a couple of photos in my gallery. One is rich, like yours and one is slightly rich but runs good.
Basicly, a WOT read should show the black band as if drawn on with a pencil.
145 main
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150 main
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After 100+ miles (not sure which main, guessing 145)
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Compliments to BJH.
A tad rich
42 and 1/2 out on the air screw.(Plug looks brand new at idle only)
7 slide ( Plug looks rich)
Needle@CEG-4. ( Bottom Mid- range wheelies)
Main at 155 (Plug looks lean to me see what you think)

1400 feet elevation at 50 degrees F
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Compliments to Morie for the link below. It came from the thread in the 2nd link.

http://www.dirtrider.net/forums3/showth ... light=plug

http://www.kdxrider.net/forums/viewtopi ... &&start=20
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"I want to die peacefully in my sleep like my grandfather, not screaming in terror like the passengers in his car."
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strider80
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Post by strider80 »

Thanks Trev, I should probably try a 150 just for fun. Seems like a 150 would be good bet for summer time.
2005 KTM 250EXC
2000 KDX200 (gone)
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strider80
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Post by strider80 »

Do I need to machine off more steel to see the full mixture ring?
2005 KTM 250EXC
2000 KDX200 (gone)
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KDXer
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Post by KDXer »

>|<>QBB<
strider80 wrote:Do I need to machine off more steel to see the full mixture ring?


Wouldn't be a bad idea. :wink:

I just spin mine up in a drill press, move a hacksaw blade back and forth until I get a good groove in it where I want to cut it off, then I grab a large nut and cross thread it onto the threads, then finally put a spanner on the plug and cross threaded nut and by twisting them against each other it snaps off cleanly.
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"I want to die peacefully in my sleep like my grandfather, not screaming in terror like the passengers in his car."
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Jeb
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Post by Jeb »

You could drop the main a size - especially since you're headed toward warmer weather - and you still ought to be alright.
"No farmer ever plowed a field by turning it over in his mind" -George E. Woodbury

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canyncarvr
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Post by canyncarvr »

The ring is a good bit thicker (wider) than 1mm..although a 1mm ring is too close to suit me.

Using ski's ring change with one jet change as a guide, dropping to 150 should make things about right.

I run a 152 in cooler temps, most of spring and summer I run a 148.

Something tells me I've read that torque spacers give somewhat confused plug reads....

Re: 'Do I need to machine off more steel to see the full mixture ring?'

No.

But doing so would make it EASIER to see.

Happy trails!

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AZRickD
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Post by AZRickD »

I'll bet you're pretty close. I use a 152/40 CEK-3 in the "cooler" months down here in Phoenix and a 150/38 in the "warmer" months. For one or two months in the freakishly-hot Arizona summer I drop down to a 148/35 and adjust the A/S just so my choke will work right.

Anyway, your chop looks just a little thicker than mine, but not much. Give up a little HP for some engine life, I suppose.

Rick
I done KX-ed QuailChaser's KDX220R
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strider80
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Post by strider80 »

I think I will leave the main for now. I am going to try a 38 pilot next time out. I know I should not jet by spooge/smoke, but the bike is slobbering quite a bit on the silencer, more than pre-RB. Seems rich to me down low.
2005 KTM 250EXC
2000 KDX200 (gone)
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