Needle to get back to the middle clip

M

m0rie

Member
Nov 18, 2002
469
0
Hey guys, i'm running a CGK-1 (top clip) and I'm trying to figure out what needle would get me back to the middle clip (-3) so I can keep tuning. Any suggestions?

-Maurice
 
C

canyncarvr

~SPONSOR~
Oct 14, 1999
4,005
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A CGK having an L1 of 39.95mm and running in the top clip position you're looking for a longer needle? Or, you've made it as long as you can and want more length to test with?

A CJK will give you an additional 1.8mm, or two clips difference. That needle in clip -3 would be the same as a CGK-1.

Something doesn't seem right, though. Generally a 'C' choice will have a shorter L1 than 39.95mm because the taper starts 'later' on the needle. I don't know why you would want a 41.75mm needle.....

Still, whatever works for you. That's the important part.

Clip positions are numbered from the blunt end, right?
 
S

skipro3

Mod Ban
Dec 14, 2002
902
0
Here is a brief explaination of what the 3 letters in your needle affect in your jetting. It may help you deside what needles to order for testing:
C of CGK: Letter > = Leaner (D leaner than C from 1/2 to 3/4 throttle) Degree of taper for the needle is greater for D than C.
G of CGK: Letter > = Leaner (J leaner than G) Overall length of the needle gets longer as letter size goes up.
K of CGK: Letter > = Leaner (L leaner than K from 1/8 to 1/4 throttle) This represents the overall diameter of the needle.

Someone correct me if I'm wrong here. I know there is MUCH more to know and understand about needles but this should at least get you started.
 
M

m0rie

Member
Nov 18, 2002
469
0
CC, I'd like to try a longer needle and see how it ends up running. However I think I ultimately need to go back up a couple of clips (CGK-3+) and re-work my jetting a bit. The bike runs strong all thru the range right now, just trying to see what more I can find. Only having the one needle i'm trying to guess which way to go, so I figured i'd pick up a few more to experiment with. I'll add a CJK to the list. Any recommendation for B and D series needles? I know you've run a BEL in your bike and have recommended others give a DDK a try.

FYI, my bike is a 89 200 with a Pro Circuit Pipe (Rev Profile) and Silencer. My jetting is currently a 155 main, 45 pilot and CGK-1. I'm running mostly 0-500ft with the occasional run to 1000+. I'm still looking for a good place to do WOT plug chop so everything so far has been set by feel.

-Maurice
 
C

canyncarvr

~SPONSOR~
Oct 14, 1999
4,005
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Yep, imo the BEL/DDK needles for a #5 throttle valve (oem in most kdxs..yours, too I believe) are something to consider. With the 'D' series you will likely be lower on your main than you are now.

Any reason you stuck with a 45 for the pilot? I'd be curious if the #1 clip on a CGK is confusing the pilot choice. 45 should be pretty rich,even for 0-500ft.

Looking at your jet profile compared to some I've used (with the obvious 'dissimilar bikes etc' disclaimer) on JD's spreadsheet the fuel delivery of a CGK-1 is hugely wonky...20 'points' high to 1/8 throttle and 30 points low at 1/4+.

Again, don't let me dissuade you from what you've determined to work best for you. That's the way it should work...what's best for you according you.

A 45 pilot with a CGK-1 doesn't compute to me.

Have you considered getting JD's spreadsheet? It's a handy 'bench jetting' tool!

Skipro:
It kinda all depends, but (for example) comparing a CEL to a DEL (other points of comparison the same) will show the 'D' taper richer than the 'C' above 3/8s. Generally, the steeper the angle, the richer the needle. 'Generally' meaning over most of the throttle range. Because a 'D' taper starts later, the bottom part of the throttle range will be more lean ('D' compared to 'C'). Using the same needles mentioned above, the 'D' is more lean than the 'C' 1/8-3/8 (roughly).

Don't confuse 'longer needle' with 'longer' L1. The needles aren't any longer, tapers just start in different places depending on the slope/taper/º chosen.
 
C

cicone

Member
Sep 29, 2003
310
0
m0rie said:
The bike runs strong all thru the range right now, just trying to see what more I can find.
-Maurice
Click to expand...

Maurice--Do you have the airbox lid off and Boyesen reeds??
If not, you'll find some more right there. FWIW, my '90 set up is--no airbox lid, boyesen reeds, pro circuit pipe and silencer, unifilter, #8 plug, 40 pilot, cel 1st or 2nd clip, 152 main---and that's too rich now that summer and 90 degree days are here at sea level---though pretty dang close to spot on when it was in the 30's and 40's a few months ago. Don't forget to check your silencer packing--it can kill your top end. :cool:
 
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M

m0rie

Member
Nov 18, 2002
469
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canyncarvr said:
Yep, imo the BEL/DDK needles for a #5 throttle valve (oem in most kdxs..yours, too I believe)
Click to expand...

The 89-94 KDX's had a #6 slide and the lower (2mm?) jet block, I don't know how much this would affect the selection of jets and needles. I've been told that this requires a richer jet set than the later carbs.


Do you think I should be trying something more along the lines of a 42 pilot and a 152 main with the CGK in the 3+ clip range? The temps here are holding around the low to mid 60's and should stay that way unless I head inland.

I've been meaning to pickup a copy of the JD jetting sheet, should just bite the bullet and get a copy :-)

Cicone - My airbox lid is completely off (wish it wasn't so I could drill some holes, but it came to me that way). When I rebuilt the top end I put in the Boyesen Pro Series Carbon Reeds.

Any other suggestions?

-Maurice
 
S

skipro3

Mod Ban
Dec 14, 2002
902
0
canyncarvr said:
Skipro:
Don't confuse 'longer needle' with 'longer' L1. The needles aren't any longer, tapers just start in different places depending on the slope/taper/º chosen.
Click to expand...

Thanks, I did just that. I guess I should have pulled out my notes instead of relying on my memory.
P.S. Can you provide a link to James Dean's site where his program can be purchased?
 
C

canyncarvr

~SPONSOR~
Oct 14, 1999
4,005
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Well, there 'ya go! Proof positive that you should pay no attention to anyone telling you what to do!! ;)

I didn't know (or fergot) that your carb had a lower jet block. That will absolutely effect L1 selection. If it's 2mm that's 2+ clips! That would make the CGK make more sense.

What pilot/main did you start with?

re: 'Do you think I should be trying...'

Pretty much. Head that direction, anyway.

You have one of those #9 plugged bikes, right? Are you running that now?

Seems you're approaching it altogether reasonably. Relatively small changes in jetting make such a big difference in performance I find it unfathomable that some riders think it's too much trouble...and so don't mess with it.

Yeah...bite that bullet! :)

Keep after it until you're happy with it! It's great fun (and a large dose of personal satisfaction) to go from being hopelessly left in the dust by a 200exc to swapping leads with a CRF-X!

**edit**

You snuck that in!! ;)

Go here . If that is a problem, go to thumpertalk.com (not a link) and search for 'jetting guide' from there.
 
M

m0rie

Member
Nov 18, 2002
469
0

I started with the stock jetting for my bike which is a 158 main and a 48 pilot with the stock funky kawi needle (1173?) and put in the 155 main and 45 pilot and then started changing positions on the CGK.

This is indeed one of the #9 plugged bikes, but i've been running a B8ES in it. Plug seems to be doing okay, no loading up, even after idling down the hills and such. I think on Saturday when I go out riding i'll reset the needle to the middle clip and drop the pilot and main 1 each and see what I get.

Edit:
I should also mention that I've been running 50:1 for the gas mix with all this jetting so thats consistant.

Second Edit:
After I've got the jetting more to my liking i'll most likely switch to one of the G series NGK's...B8EG?

-Maurice
 
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C

canyncarvr

~SPONSOR~
Oct 14, 1999
4,005
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You can use premix ratio changes to test rich/lean with. It's really not as easy as just changing some brass, but it works. 50:1 is a richer air/fuel mix than most riders use I'd guess.

Why...if the jetblock is 2mm lower than the 'H' PWK is the stock clip richer (-4) and the diameter smaller?

Port timing on these bikes is different, isn't it Mr. Jason?

You might try one thing at a time. Changing two clips should show quite a change. A more lean main and pilot thrown in and where are you going to be?

You know your bike better'n anyone else. I'd be nonplussed with so many things being changed at the same time.

Cicone's setup seems to be in the ballpark.

You're going to be pretty excited when you find what's lurking in that green thing of yours........ ;)
 
M

m0rie

Member
Nov 18, 2002
469
0
CC, i'll take your advice and start with just the clip change for now. We are just going to be riding the trails around my parents house on saturday so after i get a little bit of time on it I can drop the pilot and/or main if it needs it.

Thanks,

-Maurice
 
M

m0rie

Member
Nov 18, 2002
469
0
Thanks JasonWho, i'll run a search and give it a look see. Never ceases to amaze me how much info there is on this board, and how helpful and friendly most of the people on here are.

-Maurice
 
G

G. Gearloose

Pigment of ur imagination
Jul 24, 2000
709
0
Hiya. FWIW, I also run a CGK, -2, 38/40 pilot. +/- depending upon the season.

I concur, thinking you need to go 'longer' than the CGK is likely derrived from your running a pilot thats still sized for the 117x series needles, and are larger in diameter.
Skinny needle Skinny pilot, Fat needle Phat pilot.

Don't drop the clip just because your putting in a smaller pilot, how on earth will you quantify the results, right?

<edit> Whoops, pardon me, I failed to notice the second page of this thread...
 
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