Jetting Needles- Urghhhhh

[jaguar]

RJ I'm just a struggling human like you trying to understand this. I'm not an engineer from keihin. I'm just going by available literature and conventional knowledge.
I don't know why you're not measuring 2.745 unless it's your old needle which may be worn down. (mine is and needs to be changed)
Yes it can be between two letters when theres not a direct match.
"I don't think so"? Do you not agree that moving a needle up higher (with a shorter L1 or a lower clip position) will make it richer? Higher means the part of the taper at the level of the jet will be smaller diameter thereby allowing more gas/oil to be sucked into the carb throat.

 

[RJ-KDX]

Jaguar; The needle that I pulled out o fmy carb has R1173L stamped on it. The straight section measures 2.692mm. That is what I am getting for the diameter.

I don't know why you're not measuring 2.745 unless it's your old needle which may be worn down. (mine is and needs to be changed)

That may be the case. I do not think it is like a BEP because of the diameter difference(.002").

How does it run off-idle and WFO if your 1173L is clipped in the top notch?

Haven't tried yet, off-idle seems to have a boggy throttle. Don't get me wrong I don't want to get into a pissing match with anyone. I put out all the info and I get back answers from people that don't have any merit to the situation. Honestly, I appreciate your help. I just get a little pissy with some folks here. :p


Also, thanks Dan. :thumb:

 

[BRush]

Originally posted by jaguar
The only difference between the 1173L and BEP is that the BEP has an L1 almost 1mm shorter which means that for the same clip position it is richer.

How does it run off-idle and WFO if your 1173L is clipped in the top notch?

jaguar,

Since the L1 dimension for a BEP needle (R1173J) is 38.15 mm, your message implies that the OEM "L" code translates to 39.15 mm.
Where did you find this kind of info (about proprietary OEM needles that have no direct Keihin N427-48xxx equivalent)?

Thanks.

 

[canyncarvr]

This is getting a bit scattered...but a couple of things.

re: Lengths inbetween letters. (This is covered on CDave's site)

Yep. The kawi needles are proprietary and therefore do not necessarily match up to a keihin #. This was noted before, but it still being asked as a question makes me wonder where the confusion is....or IF there is any.

When there is a proprietary issue (ie: an 'L' for 'L1') you can either measure the L1 or take the available numbers on either side and determine a middle-ground #. The 'middle' isn't necessarily where the proprietary needle actually FITS, but it will give you an idea. Doing it 'mathwise' you get a 39.27L1 for a kawi 'L' needle...that 'L' falling on either side of an oem 'F' and 'G', or 38.60 and 39.95. While that's not 39.15, I don't imagine most riders are going to be dealing with .12mm clip level changes.

An NGK 'G' series plug is a fine wire center electrode. A sharp edge to electrodes being important to a good spark, a fine wire is more likely to spark better/longer. Personally, I found a considerable improvement in a 'G' compared to an 'ES'.

But then, I found I had a better spark with an electrex lighting coil, too. So shoot me!

re: white plug with the BEP.

Who says that's a bad thing? I don't want to pollute this thread with answers that don't have any merit, but check this:

http://www.dirtrider.net/forums3/showthread.php?s=&threadid=60392&perpage=20&display=&pagenumber=1

to see where you read mixture evidence on your plug. It's not color. Granted, if your plug heat range is correct then the TEMPERATURE of the nose is indicative of A/F mixture. INDICATIVE!! Not a direct 'measurement'.

That said, an NGK rep told me that they came up with an '8' for the KDX for a reason...that is was the correct plug for the bike. BTW...he also said that running a projected nose plug would be hazardous to the health of your bike, so don't do it!

Log? Keep a log? I don't need no steenking log!! I remember it all!!!

...now then........where did I put my keys??? ;)

 

[RJ-KDX]

CC; You crack me up sometimes. That thread you posted, I stumbled across it a while back. Hence:

and I've cut the shell away and have a carbon ring about .125" thick from the base up.

Although I haven't cut the plug I used on Saturday, I'm going to guess that things haven't changed. BTW, I looked at the plug last night and, the first couple of threads have oil and are black. The nose is medium brown(wifey has the camera :( ).

re: white plug with the BEP. Who says that's a bad thing? I don't want to pollute this thread with answers that don't have any merit, but check this:

I know what you're thinking, but I'm talking white, WHITE, looked like I just pulled it out of the box. I was under the impression that you want something at least slightly tan. No?

The other issue is the line of goo down the silencer. This would imply running right? No?

Hhhhmmmm...... :silly:

 

[canyncarvr]

I got lost somewheres.

I recognize the first quote above, but am not sure where it came from. I don't find it (searching this or the referenced thread). Actually seems like something you said once.

Anyway, I remember thinking at the time that .125 (1/8") is a pretty good sized carbon ring. Too big. Too big=too rich. Look at the ring on RR's cutaway plug..his first pic in the above thread. It doesn't look like 1/8" to me and he says he could still go one jet-size leaner.

IF it's just white, and not a blistered, coated or damaged white then you're probably real close to correct temperature-wise.

A 'line of goo' is indicative of a too rich mixture. Keep in mind how many circuits there are in a carb...and that the plug check (done right) shows you what the mainjet circuit is doing. Most of the time you don't ride there. I don't anyway. You can have a spot-on main and still have goo.

Still, goo is too rich.

Note that the flat of the threads is also a place to read A/F mixture.

Don't get a headache over this stuff. A change here and there over time with attention paid to what the result is will get you a nice list of what jetsets run the best where.

Ooops. Did I say list? OK......so I do have one!! ;)

Have fun!!! (That's an order!)

 

[RJ-KDX]

Thanks again CC. The first quote is from my first post(not sure how to put members names in quotes). Anyhoo, yeah I agree about not riding on the main most of the time. We only have one place to ride where we can get the bike out of 4th.

I've almost gone back to stock, except for a #40 pilot. It doesen't help that everytime I go ride the temp is going lower, but the first thing I'm going to change is the needle to the 5th clip(or is it the 1st clip, the leanest position). Then from there, I'll see if I need to go down another pilot leaner.

Baby steps, baby steps, and trust me I've been documenting all of this.

:worship:

 

[jboomer]

I'm still trying to figure out where you got those numbers from for your needle. My needle says NAFF, so does the service manual. I can't find any kind of reference as to a part number or anything else. The dealer has no clue as to how to order a leaner needle. Any body feel like trying to "break the code" on my needle so I too can go leaner with it? Clips already in the top position and I'm still fat at 1/2 throttle.

 

[RJ-KDX]

http://www.buykawasaki.com/Default.asp?strContentURL=site/VIVehicleInformation/VIChooseVehicle.asp?intCatalogID=2&intParts=1

You might want to try Kawasaki.com. There are a bunch of needles to choose from, as far as which one, who knows. Try posting in the CR,KX,RM,YZ forums. :aj: