Jump to content

decoding keihin needles


Recommended Posts

I am trying to do some needle testing for my 97 rm250.

Rather than trial and error, I was hoping to take a semi-intelligent approach.

stock needle is too rich, tried a fat needle that is a bit too lean.

turns out I have access to a bunch of needles to try, but I need help decoding the numbers. There seems to be little info about some of the multi taper needles. I have read the charts on the keihin site and have searched here.

I found a post that says the following...

SIZE: P/NO Dia.

NOZF 13383-37EB0 2.705mm

N1EF 13383-37E60 2.705mm

N0ZE 13383-37EA0 2.695mm

N1EE 13383-37E50 2.695mm

NOZD 13383-37E90 2.685mm

N1ED STOCK NEEDLE 13383-37E40 2.685mm

N0ZC 13383-37E80 2.675mm

N1EC 13383-37E30 2.675mm

N0ZB 13383-37E70 2.665mm

N1EB 13383-37E20 2.665mm

seems to indicate f=2.705mm E=2.695mm D=2.685mm and so on...

first: I have not seen any keihin docs that verify this (straight needle Letters mean something different)

second, I do not have and info on tapers...

Has anyone here straightened this out?

Link to comment
Share on other sites

I think the chart you posted is an example of why I need more information...

The needle sizes I posted can not be decoded using the chart you posted...

Mine is a PWK, but the charts for PWK needles are like this one for the FCR. The diameter markings do not match up.

If keihin is not the right source for the info where is? specifically for the NOZ(X) and N1E(X) needles

Link to comment
Share on other sites

You need to look closer at the chart. AFAIK, the codes and relationship to numerical values is consistent.

Each letter for taper is 1.5 degrees

Each letter for length is .5mm

Each letter for diameter is .01mm

As I said in my first post, those needle designations you provided are OEM ones, not Keihin.

BTW, the N1E probably is really a NIE

Link to comment
Share on other sites

I think the chart you posted is an example of why I need more information...

The needle sizes I posted can not be decoded using the chart you posted...

Mine is a PWK, but the charts for PWK needles are like this one for the FCR. The diameter markings do not match up.

If keihin is not the right source for the info where is? specifically for the NOZ(X) and N1E(X) needles

As William said these 4 digit needles are O.E.M. They may be made for the O.E.M.'s by Keihin but they do not use the same code as the Keihin 3 digit PJ/PWK needles. The reality is that the first 3 digits of the 4 digit code are random, no value has been tagged to the individual letters but as a group they do designate the needles design. However the last letter in the 4 digit code does determine the straight section diameter (starting diameter). The diameters you posted for B,C,D,E, and F are correct but as you may have noticed, they are not the same as the 3 digit diameters. They will continue to increase in size by .01mm as you move up the alphabet with the exception being W. W is the same diameter as I 2.735mm. FWIW NOZ and N1E (and yes it is N1E) are of the same design except that the tapers on N1E are moved 1/2 clip position (.45mm) closer to the clip grooves then the tapers on NOZ (think L-1, but in reality with these triple taper needles it's L-1, L-2 and L-3). The end result then is that N1E is 1/2 clip richer than NOZ, meaning N1EF in clip 2 is the same as NOZF in clip 2.5.

Link to comment
Share on other sites

The stock needle I have clearly looks like a 1, and the clymer manual has it listed as a 1 as well.

From the keihin charts on diameter...

H 2.675

K 2.695

L 2.705

M 2.715

from some other guys post on the NOZ and N1E needles...

B 2.665

C 2.675

D 2.685

E 2.695

F 2.705

so it appears that this this series has a different lettering scheme, but I have not yet found a doc that describes it.

Link to comment
Share on other sites

I will take my caliers and mesure all this guy's NOZ needles to verify, but it sounds like there isn't a clear doc on taper specs for these huh

The calipers will confirm what you already know, here's a pic of what looks like a Kawasaki doc. that details the two needles. Sorry about the size but if you look closely you'll find the diameters for C,D,E,F and G. The 3 taper angles 1st= 0degrees 30min, 2nd= 1degree 34minutes 40seconds, 3rd= 3degrees. The .9mm between clip grooves and the .45mm difference between NOZ and N3E at L-1, 2 and 3. The note under the chart sums it all up!!

002-3.jpg

Link to comment
Share on other sites

  • 11 months later...

Create an account or sign in to comment

You need to be a member in order to leave a comment

Reply with:

×
×
  • Create New...