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Mikuni

pilot jets
bs30/96
151067
vm28/486

pilot air jets
n100.606
n102221

needle jets / OEM(!) CV emulsion tubes
all emu tubes are Factory Pro exclusives

main jets
n102221 (small round slotted),
n100604 (large round slotted),
n208099 (those weird Duc/TDM,yzf750 jets),
N4/042 "Mikuni "Hex" jets

main air jets: n100.606 and n102221

power jets: n100604
 

Pilot jets

Mikuni Pilot Jets
Mikuni

BS30/96 series

"the short ones with holes" - OEM CV type Carburetor
3.8mm Slot head
M5x0.8 Thread
14.0mm length
6 Bleed holes
We have a wide range of sizes in stock
Mikuni

151.067
non-emulsion version of the bs30/96

Commonly called: "The 30/96 pilots without the holes." Duc's, Yamaha's and lots of others We have a wide range of sizes in stock
Mikuni

VM22/210
"210 Series"

"These pilots are measured on a different scale than 30/96 and 151076" Used in:
old 2 stroke apps and an  ancient, few 4 strokes
4.0mm Slot head
M5x0.8 Thread
13.5mm length
1.7mm Bleed holes
8 Bleed holes
Don't interchange with the 30/96 or 151067's! The size scaling is different.
Not generally stocked.
Mikuni

VM28/486-xx

long style
with air emulsion holes
Fits RS36mm, RS38mm, TM33mm
5.0mm Slot head
M4 Thread
28.0mm length
2.0mm Diameter bleed tube
8 Bleed holes
We have a wide range of sizes in stock
Mikuni

224/103-xx

long and similar to VM28/486
but 1 groove cut around OD
GENERALLY interchangeable with 28/486
OEM TMX36mm Yamaha, Honda, Suzuki
5.0mm Slot head
M4 Thread
28.0mm length
2.5mm Diameter bleed tube
8 Bleed holes
We have a wide range of sizes in stock

Mikuni 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

We have a wide range of sizes in stock

Mikuni emulsion tubes / needle jets

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  "Emulsion" Tubes   /   Needle jets

            emuwr3.jpg (9351 bytes)

This is way more than enough wear to cause overrich low speed 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. In fact - I'll GIVE any carb needle jet rebuild to any VL 1500 owner who makes it to 60,000 miles on the original needle jets!  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 highly optimistic 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.

Be famous! (for something besides "that"!)
Have an emulsion tube that's worn? Send it in (in a padded envelope) with make, model, mileage, usual use (in-town, commute or sport), your name and the difference between running before and after replacement. We'll put some of them at the bottom of this page.

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 and Factory Pro "M221 and M604 Replica 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
$56 / 2pcs
1. Choose your shipping method
2.
 

Ducati

Ducati

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

~3.00mm Ø
(.1175 kit)

Factory Pro nickel plated replacements in stock CRZ-EMU-100120k
(nickel plated!)
$64 / 2pcs
1. Choose your shipping method
2.
 

Suzuki

Suzuki

gsf 1200 "Bandit" 96-00
all countries
(does not fit the 01 and later Bandit 1200's - they are pressed in and not easily replaced)

replaces pn: 09494-00898 (O-8)

36mm CV

~2.5mm
(.0985-.0990)

Factory Pro nickel plated replacements in stock CRZ-EMU-100102k
$128 / 4pcs
1. Choose your shipping method
2.
 
Suzuki

gsxr11000, 89-98
US, CA

36mm CV

~2.5mm
(.0985-.0990)
Factory Pro nickel plated replacements in stock CRZ-EMU-100102k
$128 / 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-1001023-(1210)

415 491 5920

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-1001023-(1220) x 4 pcs  $132

1. Choose your shipping method

2.

Suzuki

gsxr750,   88-89,  USA only (not 90-92 USA)

36mm CV, ~3.00mm,
(.1175 kit)
Factory Pro nickel plated replacements in stock CRZ-EMU-1001023-(1220) x 4 pcs  $132

1. Choose your shipping method

2.
 

Suzuki

gsxr750,   88-92, all CA

36mm CV 
~3.00mm
(.1175 kit)
Factory Pro nickel plated replacements in stock CRZ-EMU-1001023-(1220) x 4 pcs  $132

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
1. Choose your shipping method
2.
 
Suzuki, rf600, 94-96
Suzuki, rf900, 94-97
yes, Suzuki used essentially the same part in both size carbs....

Suz pn:
09494-00810 (900)
09494-00872 (900)
09494-00854 (600)
09494-00814 (600)
These are all interchangeable. The top 3 are "O-9" and the bottom one is an "O-8". The theoretical difference in size between an "O-8" and an "O-9" is below any realistic manufacturing tolerance)

Factory Pro nickel plated replacements in stock

CRZ-EMU-100195k
$112 / 4pcs
1. Choose your shipping method
2.
 
Suzuki

VL1500
all carbureted

  nickel plated HDJ Send in for rapid turnaround repair / rebuild
click here

Triumph

Triumph 900
3 cylinder, 36mm CV Mikuni carbs

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

Factory Pro nickel plated replacements in stock CRZ-EMU-100102k
3pcs
1. Choose your shipping method
2.
 
Triumph 1200
4 cylinder, 36mm CV Mikuni carbs

~2.5mm
(.0985-.0990)

Factory Pro nickel plated replacements in stock CRZ-EMU-100102
$112 / 4pcs
1. Choose your shipping method
2.

Yamaha

Yamaha

fzr400 - 1WG
88-90 USA and others, w/ 1WG carbs.

(yam pn: 1WG-14141-90-00)

Discontinued by Yamaha at last suggested retail of about $180 for 4 pcs.

Factory Pro used to do a lot of race work (3rd OA in 24 Hour) for the venerable fzr400, so we tooled up and made a limited run of emulsion tubes to keep these classic bikes running right.

Factory Pro nickel plated replacements in stock CRZ-EMU-100105k
$148 / 4pcs
1. Choose your shipping method
2.
 
NEW!

Yamaha

 fzr400  -  3EN & (3TJ?)

(yam pn: 3EN-14141-90 or 92)

Factory Pro nickel plated replacements in stock CRZ-EMU-100160k
$132 / 4pcs
1. Choose your shipping method
2.
 
Yamaha

fzr600, 89-99 USA
89-93 rest of the world
(not for yzf Thundercat)

Factory Pro also used to do a lot of race work for the long running fzr600,. We used that knowledge and built a stronger, longer lasting,  "better than original" emulsion tube.

 

Factory Pro nickel plated replacements in stock CRZ-EMU-100160k
$132 / 4pcs
1. Choose your shipping method
2.

Yamaha

yzf750, 93-99

Yam pn: 3GM-14141-90-00
Yam pn: 3GM-14141-92-00 Yam pn: 3GM-14141-94-00
 and all 3GM
(aprox. Yam price $40 to $60 each)

38mm CV
~3.00mm
(.1175 kit)
Factory Pro nickel plated replacements in stock

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").

CRZ-EMU-100120k
$132 / 4pcs
1. Choose your shipping method
2.

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

Yam pn: 3GM-14141-90-00
Yam pn: 3GM-14141-92-00 Yam pn: 3GM-14141-94-00
(aprox. Yamaha price $40 to $60 each)

38mm CV
~3.00mm
(.1175 kit)

Factory Pro nickel plated replacements in stock

 

CRZ-EMU-100120k
$132 / 4pcs
1. Choose your shipping method
2.

Yamaha
tdm850, 92-93
xtz 750, all years

replaces Yam pn: 3GM-14141-94-00
(aprox. Yam price $40 to $60 each)

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

(does not fit 99-00 TDM's)

(does NOT fit 90-92ish gsxr750 horizontally mounted 38mm carbs - email for those)
 

Factory Pro nickel plated replacements in stock

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)

CRZ-EMU-100120k
$64 / 2pcs
1. Choose your shipping method
2.

Yamaha
fj1100, 84-85

84 1100 Yam pn: 16H-14141-90-00
85 1100 Yam pn:   50h-14141-92-00
(same part number as the fj1200)

84 1100 models are upgradeable to the later style "50H" 1200 parts.

Factory Pro
nickel plated
replaces stock parts seamlessly - atomizes fuel better for better mileage and power.

HDJ style!
for better fuel atomization and response

CRZ-EMU-100112k
$132 / 4pcs
1. Choose your shipping method
2.
 
Yamaha
fj1200, 89-93

Yam pn: 50H-14941-92-00

Factory Pro
nickel plated
replaces stock parts seamlessly - atomizes fuel better for better mileage and power.

HDJ style!
for better fuel atomization and response

CRZ-EMU-100112k
$132 / 4pcs
1. Choose your shipping method
2.
  
Emulsion Tube / Needle jet

Yamaha
V Max and VMX1200 - 85-07

replaces Yam pn: 26H-14941-90-00

Factory Pro

HDJ

replaces stock Yamaha tube

nickel plated
replaces stock parts seamlessly - atomizes fuel better for better mileage and power.
CRZ-EMU-100XXXk 
HDJ Hi Dispersement Jet style
$120 / 4pcs
Intro Special
1. Choose your shipping method
2.
 
Emulsion Tube / Needle jet

Yamaha
Venture Royal - XVZ1200, 85

Yam pn: 26H-14941-90-00

Factory Pro

HDJ

replaces stock Yamaha tube

nickel plated
replaces stock parts seamlessly - atomizes fuel better for better mileage and power.
CRZ-EMU-100XXXk 
HDJ Hi Dispersement Jet style
$120 / 4pcs
Intro Special!
1. Choose your shipping method
2.
 
Emulsion Tube / Needle jet

Yamaha
Venture  - XVZ1300, 86-93

Yam pn: 26H-14941-90-00

Factory Pro

HDJ

replaces stock Yamaha tube

nickel plated
replaces stock parts seamlessly - atomizes fuel better for better mileage and power.
CRZ-EMU-100XXXk 
HDJ Hi Dispersement Jet style
$120 / 4pcs
Intro Special!
1. Choose your shipping method
2.
   
xv250,95-11
fzr400,88,89 (1WG-14141-90-00??)
xj600, Seca, 92-98
V-Star xvs650, 98-05
fz750, 85-86
fzx700,86-87
Royal Star, xvz1300 96-01
Royal Star, xv13,98-01

yam pn: 1AE-14261-00-00
     
       

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.

Mikuni main jets

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 We have a full range of sizes in stock
N100604 Commonly known as:
"Large, round, slotted"
Used in original equipment CV carbs on some Kawasaki, some Yamaha, Mikuni equipped Triumph We have a full range of sizes in stock

temp picture
N208.099 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.
we have a range of sizes in stock
Mikuni
Hex Mains

N04042

5mm thread diameter

6mm hex width
many offroad / dirt, TZ250, all to at least 02 we have a range of sizes in stock

main and pilot air jets / power jets
 

Mikuni Power Jets

N100.606-xx Commonly called "What's a power jet?" used in:
TZ250, all to at least 08
gsxr750,90-92,all with 38 Mikuni carbs
 
  N100.607-xx Air Jet
Common in stock CV carbs for the pilot circuit, and in some carbs, as the "Main Air Jet (MAJ)
   

carb tools

Mikuni Needle Jets / Emulsion Tubes

UNDER CONSTRUCTION!!!!