pilot jets

Pilot jets (aka "slow jets") Keihin
21 series   OEM Honda CV carbs  
22 series      
  25 series   OEM Kaw CV carbs
FCR "Flatslides"
 
  26 series   OEM Honda dirt bikes w/ CV carbs +  
78 series aka:

"I can't find these damn jets anywhere!"

98-02 Yamaha R6

00-01 Kawasaki zx9r

KTM Adventure / SM 950

from #38 to #45 - Factory Pro is the only manufacturer of these optional pilot jets.

 

Mikuni Pilot Jets
BS30/96 series "the short ones with holes" -    
151067
non-emulsion version of the bs30/96
Commonly called: "The 30/96 pilots without the holes." Duc's, Yamaha's and lots of others  
  210 Series "These pilots are measured on a different scale" Used in:
old 2 stroke apps and an  ancient, few 4 strokes
Don't interchange with the 30/96 or 151067's! The size scaling is different.
  VM28/486-xx long style early CV carbs  
  151067 long and similar to VM28/486, but with a single ID groove around the circumference. later style CV carbs  

pilot air jets

Mikuni Air Jets  / also used as "Power Jets

    5mm thread    
N100.606-xx 4mm thread When you need a 4mm thread, small diameter headed air or fuel jet - this is the usual jet of choice.

Air jets in most carbs and the power jets in TZ250 carbs and 90-92 gsxr750's with 38mm carbs

 

emulsion tubes / needle jets


Emulsion Tubes, Mikuni, Hitachi and others:  Worn needle jet orifice

tech reference:
Identify emulsion tubes and needle jets, Mikuni

Identify Yamaha Virago emulsion tubes and needle jets

Identify Honda VTR1000 emulsion tube / needle jet front and rear

Mikuni / Hitachi / Keihin "Emulsion" Tubes  
emuwr3.jpg (9351 bytes)

 

 

This is enough wear to cause problems.

Top Left side - This is a picture of the needle jet area of an emulsion tube from a stock 38mm CV Mikuni carb as installed on Ducati,  Yamaha TDM/TRX 850, YZF750, FZR1000, etc..
It has approximately ~5000 miles or  8000k usage on a Ducati or TDM 850 - WITH A STOCK Aluminum NEEDLE.
Notice that the center hole is noticeably worn at the "V", the 12 o'clock position, which would be towards the engine, as installed in the carburetor.
This causes 2 conditions. First, it allows more fuel to enter the carburetor, as in using a needle with a small base diameter AND the fuel that enters the carb - it enters in larger droplets, resulting in poor combustion.
We carefully check needle jet condition on the vehicles when we create and install carb recalibration kits.
If you install a kit and it is much too rich at low rpm, and lowering the fuel level 1mm doesn't fix it, check the needle jets for any wear - it's not uncommon.

Additional:
  Eventually, in the 36mm horizontal mount and 38mm downdraft Mik's, the carb body plastic insert, where it holds and guides the slide from rattling back and forth, will wear out - allowing the slide to rattle and bang the needle fore and aft in the needle jet orifice - causing accelerated NJ wear. This wear is biased towards the lowered slide position - as in idle and low rpm areas - as in "in-town", "stop and go" driving.
The gist of that is that you may only get 5,000 miles out of your needle jets in your VL / VS bike that you use for cruising 4th Street and hanging out at McDonalds - but your long distance , highway cruising buddy might get 25,000 miles before mileage deteriorates to 25mpg or worse.
I haven't heard of anybody who has got the "60,000 miles" that some Tech Bulletin claims is normal with a stock needle...... I WILL change this if I ever find that person who made it to 60,000 miles on his/her VS / VL and has the original needle jets/emulsion tubes.  Marc

Slide Guide Wear:
Example: The original needle jet lasted 5,000 miles in your usage. After replacing the worn emulsion tube / needle jet, they only lasted 3,000 miles or less. That's because the slide guide slot in the carb body is worn - not because of the emulsion tube or needle is bad.
Even Suzuki knows that - even though their estimate of 60,000 mile life with a stock needle is based on perhaps a VL1500 or VS1400 run at high speed on a highway.

A "step" inside of the needle seat in the carb slide?
It's there in virtually every Mikuni CV carb. It's supposed to be there.
It's to try to keep the needle bearing onto only one side of the needle jet - otherwise, the needle bangs back and forth onto both sides of the needle jet at idle and low rpm, instead on only one side.
Of course, if one "notches" the plastic needle shim, they are lowering the needle about 2 clip positions and that will lean out the mixture, but that doesn't really permanently fix anything.

US=USA
CA=California
CN=Canada
Aus=Australia
SW=Switzerland
FR=France
UK=United Kingdom
Euro=all European countries

 

Factory produces stock replacement needle jets / emulsion tubes for Mikuni carburetors

These Factory Pro Design "Mikuni style" needle jets are threaded for Genuine Mikuni or Factory Pro "M221 Series" main jets, but not dynojet.

Aprilia

Pegaso 650

36mm CV

~2.5mm
(.0985-.0990)

  Factory Pro nickel plated replacements in stock CRZ-EMU-100102k
$66 / 2pcs
1. Choose your shipping method
2.
Ducati

M600, M750, M900
900 ss/cs/sp   38mm CV

~3.00mm
(.1175 kit)

Factory Pro nickel plated replacements in stock CRZ-EMU-100120k
(nickel plated!)
$74 / 2pcs
1. Choose your shipping method
2.
Suzuki

gsx/gsf 1200 96-00
"Bandit"
all countries

36mm CV

~2.5mm
(.0985-.0990)

  Factory Pro nickel plated replacements in stock CRZ-EMU-100102k
$132 / 4pcs

1. Choose your shipping method

2.

Suzuki

gsxr1100, 89-98
US, CA

36mm CV

~2.5mm
(.0985-.0990)
  Factory Pro nickel plated replacements in stock CRZ-EMU-100102k
$132 / 4pcs

1. Choose your shipping method

2.

Suzuki

gsxr600, 92-93 only

36mm CV

~3.00mm
(.1175 kit)
"693, X-8"

  Factory Pro nickel plated replacements in stock CRZ-EMU-100102k1221

$132 / 4 pcs

1. Choose your shipping method

2.

Suzuki

SV650
all carbureted

    Send in for repair / rebuild
click here
Suzuki

gsx750, Katana   89-97

36mm CV

~3.00mm
(.1175 kit)
"Y-1 or Y-2"

  Factory Pro nickel plated replacements in stock CRZ-EMU-100102k1221
$132 / 4 pcs

1. Choose your shipping method

2.

Suzuki

gsxr750,   88-89
US only

36mm CV
~3.00mm
(.1175 kit)
  Factory Pro nickel plated replacements in stock CRZ-EMU-100102k1221
$132 / 4 pcs

1. Choose your shipping method

2.

Suzuki

gsxr750,   88-92
CA only

36mm CV 
~3.00mm
(.1175 kit)
  Factory Pro nickel plated replacements in stock CRZ-EMU-100102k1221

$132 // 4 pcs

1. Choose your shipping method

2.

Suzuki

gsxr750,   93-95
CA only

36mm CV
~2.5mm
(.0985-.0990)
  Factory Pro nickel plated replacements in stock CRZ-EMU-100102k
$132 / 4pcs
Suzuki, rf600
Suzuki, rf900
yes, Mikuni used the same part in both size carbs....

Suz pn:

Factory Pro nickel plated replacements in stock

CRZ-EMU-100195k
$132 / 4pcs
Triumph 900
(with Mikuni carbs) 36mm CV

~2.5mm
(.0985-.0990)
all countries

  Factory Pro nickel plated replacements in stock CRZ-EMU-100102k
3pcs

International buyers will be billed an additional $18 for Express shipping
Triumph 1200
(with Mikuni carbs) 36mm CV

~2.5mm
(.0985-.0990)

  Factory Pro nickel plated replacements in stock CRZ-EMU-100102
$132 / 4pcs

Note! Add $14 additional for international shipping.
Yamaha

fzr400
88-90 USA and others, as similar carbs.

(discontinued by Yamaha - only available from Factory Pro, as of July, 06)

Factory Pro nickel plated replacements in stock CRZ-EMU-100105k
$132 / 4pcs


Note! Add $14 additional for international shipping.

Yamaha

fzr600, 89-99 USA
89-93 all other worlds

(yam pn: 3EN-14141-90-00)

Factory Pro nickel plated replacements in stock CRZ-EMU-100160k
$132 / 4pcs

intl customers add $18

Yamaha
yzf750, all years

Yam pn: 3GM-14141-94-00

In the original carbs, there are tiny differences in the "size", but, if you know what I'm talking about, a Y-2 and a Y-4 are the equiv. of  <1/3mm difference in float height (translate to "insignificant").


38mm CV
~3.00mm
(.1175 kit)

Factory Pro nickel plated replacements in stock
 
CRZ-EMU-100120k
$112/4pcs

Note! Add $38 additional for international shipping.
Yamaha

XV750

Hitachi
Factory Pro nickel plated replacements in stock CRZ-EMU-XV750
$72 / 2pcs

Note! Add $14 additional for international shipping.

Yamaha
fzr1000, all years (but not "ThunderAce")

Yam pn: 3GM-14141-94-00

38mm CV
~3.00mm
(.1175 kit)

Factory Pro nickel plated replacements in stock

 

CRZ-EMU-100120k
$112/4pcs

Note! Add $14 additional for international shipping.

Yamaha
tdm850, 92-93
xtz 750, all years

Yam pn: 3GM-14141-94-00

Also same part used in Ducati 600, 750 and 900cc bikes. Fits every original Mikuni 38mm downdraft CV carb.

In the original carbs, there are tiny differences in the "size", but, if you know what I'm talking about, a Y-2 and a Y-4 are the equiv. of  <1/3mm difference in float height (translate to "insignificant").

~3.00mm
(.1175 kit)

Factory Pro nickel plated replacements in stock

CRZ-EMU-100120k
$74/ 2pcs


International buyers will be billed an additional $18 for Express shipping

Yamaha

XV1000
XV1100

Hitachi

Factory Pro nickel plated replacements in stock CRZ-EMU-XV10/11
$72 / 2pcs

International buyers will be billed an additional $18 for Express shipping
Yamaha, fj1100, 84-85

84 Yam pn: 16H-14141-90-00
SUPERCEDED TO:
85 Yam pn:   50h-14141-92-00

Factory Pro nickel plated replacements in stock CRZ-EMU-100112k
$168 / 4pcs


International buyers will be billed an additional $18 for Express shipping

 
Yamaha, fj1200, 89-93

Yam pn: 50H-14941-92-00

Factory Pro nickel plated replacements in stock

CRZ-EMU-100112k
$168 / 4pcs

International buyers will be billed an additional $18 for Express shipping

 

needles

Keihin
FCR Flatslide needles
    FCR and Smoothbores only I got really tired of trying to use the original Keihin numbering / profile codes, so I made my own.
Very nice if you have everything perfect at every throttle position except for 1/4 and only want to change that 1 thing!
Flatslides are super easy to tune on the EC997 dynos and not easy on anything else for many different reasons.

needle clips

needle shims

Emulsion Tubes, HDJ

emutube2.gif (588470 bytes) emuhidisp.gif (281690 bytes)
patented High Dispersal Jet System
HDJ

 available for licensing
Easily retrofitable in many OEM Keihin, Mikuni and aftermarket carbs and simple to make minor modifications in manufacturing process to incorporate.
Significantly better fuel atomization, runs without misfire at leaner fuel delivery rates, better power from the same amount of fuel, more consistent, smooth running, as verified on
EC997 Low Inertia dyne FLUX value engine smoothness testing. I can explain that if you are not using that dyne system and cannot get that data.
All what an MJN promised, but it can run cleanly at all rpms and, because it still used a tapered needle, is easy to tune properly.

main jets

Main Jets

STYLE Slang.... Where usually used Notes
"Keihin style"
mfg by Factory Pro.
Uses the same number size scale as original Keihin jets.
393 Series
(5x.75 thread)
Commonly known as:
"Small, round, slotted"
used in original equipment CV carbs on Honda, Kawasaki, Keihin equipped Triumph and some Yamaha Range:
 We make larger upper range and lower smaller range than usually available from importers:

#50-#200 in 2.5 increments:
#205 to #250 in 5 increments
"Keihin style"
mfg by Factory Pro.
Uses the same number size scale as original Keihin jets.
806 Series
(6x1.00 thread)
Commonly known as:
"the big thread, round jets for the HD"
Used only in original HD and some European 94-97 ZX9 carbs as far as I can see. Range: larger upper range

#160 to #200 in 2.5 increments
#205 to #250 in #5 increments

  357
"Hex" Series
Commonly called "Keihin Hex jets" Used in most Keihin FCR's, Smoothbores and some dirt bikes. OEM Keihin - in  stock

 

Mikuni Main Jets

N102221 Commonly known as:
"Small, round, slotted"

Looks a lot like a Keihin 393 series jet, but the threads are slightly different

Used in original equipment CV carbs on some Kawasaki, some Yamaha, Mikuni equipped Triumph  
N100604 Commonly known as:
"Large, round, slotted"
Used in original equipment CV carbs on some Kawasaki, some Yamaha, Mikuni equipped Triumph  
  N208099 Commonly known as:
"Those weird push-in jets that I can't find"
Used in Ducati 600, 750, 900 w/ Mikuni's and TDM/TRX 850.
Used in YZF750 in some countries, in some years. USA always used these jets in the yzf750.
 
  Hex Mains   Older dirt, TZ250, all to at least 02  

main air jets

power jets
 

Mikuni Power Jets

N100.606-xx Commonly called "What's a power jet?" used in:
TZ250, all to 02
gsxr750,90-92,all with 38 Mikuni carbs
 

carb tools

Mikuni Needle Jets / Emulsion Tubes

UNDER CONSTRUCTION!!!!

 

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