Pro X 99101-357 Series Keihin Hex Main Jet

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Pro X 99101-357 Series Keihin Hex Main Jet
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Pro X 99101-357 Series Keihin Hex Main Jet

Our Price: $2.24

MSRP: $2.60 - $13.01 - You save up to $10.77 (83% off)

View Product DetailsSee stock sizes for your machine (Machine Specs)

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Details

  • 99101-357 Style.
  • High quality aftermarket jets for Keihin carburetors.

Pro X 99101-357 Series Keihin Hex Main Jet Reviews

Each review submitted enters you into a
$100 gift card monthly drawing and a
$500 gift card quarterly drawing!
 
4.9 / 5.0
154 Reviews
5 Stars
4 Stars
3 Stars
2 Stars
1 Stars
140
10
3
0
1
Value
5.0 / 5
Performance
5.0 / 5
Recommend it?
Yes (38)
No (1)
Value
5 / 5
Performance
5 / 5
Recommend it?
Yes
A
Very satisfied with the pro x jets and needles they are just as good as keihin
February 12, 2018
Clover , SC, US
Age: 25-44
Purchased
5 months ago
Gender:
Male
Weight:
221 - 250 lbs.
Height:
6'1 - 6'3
Value
5 / 5
Performance
5 / 5
Recommend it?
Yes
Main jet
Always nice to have spare jets

-m-1987 HONDA TRX 250R FOURTRAX--
January 28, 2018
Ellsworth, WI, US
Age: 25-44
Purchased
1 month ago
Gender:
Male
Weight:
191 - 220 lbs.
Height:
5'7 - 5'9
A+++
FIts perfectly, works perfectly, only thing is it isnt marked on the jet what size, small issue but not a real problem by any means
December 30, 2017
Philadelphia, PA, US
Age: 25-44
Value
5 / 5
Performance
5 / 5
Recommend it?
Yes
02 Honda Reborn
Good product, Great performance. Made my 02 Honda run a whole lot better! Thanks

-m-2002 HONDA TRX 400EX--
December 8, 2017
Houston , TX, US
Age: 45-64
Purchased
3 months ago
Gender:
Male
Weight:
161 - 190 lbs.
Height:
5'7 - 5'9
Value
5 / 5
Performance
5 / 5
Recommend it?
Yes
Works as it should
No gimmicks, just a trusty jet that does its job day in day out!

-m-2016 YAMAHA YZ250--
November 29, 2017
Boise, ID, US
Age: 25-44
Purchased
5 months ago
Gender:
Male
Weight:
161 - 190 lbs.
Height:
5'10 - 6'0
Value
5 / 5
Performance
5 / 5
Recommend it?
Yes
Great
It’s a jet like they described and it works in my 34mm pj carbs
November 27, 2017
Baton Rouge , LA, US
Purchased
3 months ago
Value
5 / 5
Performance
5 / 5
Recommend it?
Yes
good jet
Needed to change out my jets so I picked this up because of the price. Fit perfect and seems to be what I needed.
November 22, 2017
Centerville, PA, US
Age: 25-44
Purchased
over 3 years ago
Gender:
Male
Weight:
191 - 220 lbs.
Height:
5'10 - 6'0
Value
5 / 5
Performance
5 / 5
Recommend it?
Yes
Great Jet
Cost effect OEM replacement

-m-2010 YAMAHA YZ250F--
November 10, 2017
Crestwood, KY, US
Age: 25-44
Purchased
8 months ago
Gender:
Male
Weight:
131 - 160 lbs.
Height:
5'7 - 5'9
Value
5 / 5
Performance
5 / 5
Recommend it?
Yes
Great OEM Alternative
Great lower cost OEM Alternative

-m-2006 SUZUKI RMZ450--
October 30, 2017
Springville, UT, US
Age: 25-44
Purchased
7 months ago
Gender:
Male
Weight:
191 - 220 lbs.
Height:
5'10 - 6'0
Value
5 / 5
Performance
5 / 5
Recommend it?
Yes
Veery close to stock
As most of you know, jets are varied in size from different manufacturers. For instance, I run a stock keihin 190 main, but if its a dynajet then its a 175 main. These pro x jets are very close to stock. If you got recommendations for jetting from an exaust company or who ever did your motor work, use these or stock keihin jets. Don't even bother with the dynajets, you'll probably end up getting them mixed up down the road. Plus, you can pull the 17mm bowl plug to see what jets you have instead of pulling the bowl off.

-m-ATV--
October 20, 2017
Spring Valley, CA, US
Age: 25-44
Purchased
6 months ago
Gender:
Male
Weight:
161 - 190 lbs.
Height:
5'10 - 6'0
Each question or answer submitted enters you into a:
$100 gift card monthly drawing and a
$500 gift card quarterly drawing!
Start typing your question and we'll check if it was already asked and answered. Learn More
Browse 8 questions Browse 8 questions and 16 answers
Have a o6 yfz 450 with a Yoshimura full exaust and a aftereally market intake . How much bigger than stock do I need to go on jet size?
A shopper on Dec 17, 2016
BEST ANSWER: Save yourself the headache and only go up 1 jet size at a time. This jets are fairly inexpensive so I usually buy 2-3 spanning the range I need along with some extra spark plugs to jet any modified bike. Remember your main jet primarily affects 3/4 to full throttle. For better throttle response be looking at your pilot jet and needle position. I hope this helps.
anybody have a guess on jet sizes for a 2005 250exc 4 stroke that usually is run at about 6000-7000 ft.?
A shopper on Sep 3, 2016
BEST ANSWER: to make it run properly you have to count outside temp humidity elevation
generally speaking more elevation smaller the jet i would recommend 2 sizes smaller then stock
beside the mail jet you will have to adjust needle position or buy a jd kit it has everything you need plus great tech support
I have a 04 yz 250, with a 182 main jet and a 50 pilot jet. When a bought the bike from the second owner with these Jets and it was rebuilt with a wisco piston rebuild kit and a fmf gnarly pipe.. since I purchased the bike I have put a pro curcuit platnum series pipe and v force 3 reeds without re jetting the keihin carb.. is there any suggestions on how many sizes to move up in the main or pilot jet? I live in Whittier CA, altitude 367' and have a few spots that I ride at.. glamis, Ca 335' altitude, gorman Ca, altitude 4160 . Stoddard wells, Ca ., Not sure the altitude but researched online and it says the elevation is 2,800-5,000'. If I can make the bike run and perform properly in the conditions that I ride the bike in then I will be happy. If there is any information any one can give me about my situation as far as re jetting my 04 yz 250 I would greatly appreciate it. I am a new rider but am extremely interested in learning about my bike and being able to tune and repair my own machine so I would dearly appreciate any comments or concerns of my situation. Thank you
Nicholas R on Sep 3, 2017
BEST ANSWER: Jump to a 190 main, keep the pilot the same. Start with a fresh spark plug so you can read the burn on the plug. You will want to run it through the powerband once it is warmed up and notice if you have any bogging out from 1/4 to half throttle. If you do then you will need to also move your needle one clip down so that it richens up the mid range as well. Once you get to full throttle, hold it open for a few seconds and then kill the ignition so that you preserve the full throttle burn on the spark plug. Pull the plug, it should have a nice tan color on it, darker tan the better. If it is white at all or cuts out on power at the top then keep stepping up in main jet increments of 5. If the plug is black and sluggish then bring down in increments of 5 until the plug is a nice dark tan color at full throttle burn.
I have a 2008 ktm 505 that cuts out on the low end I ride between 6500-8500 above sea level but I can not for the life of me find a chart can anyone tell me what size jets I need to run? Thanks in advance!!!!
samual L on Jun 20, 2017
BEST ANSWER: Jet Correction Chart ...... Example: 160 Stock Jet x 0.89= 142 Main JetAltitude - Meters0m500m1000150020002500300035004000Altitude - Feet0'1500'3000'4500'6000'7500'9000'10500'12000'Temperature -22F [30C]1.041.031.011.000.980.970.950.940.93-4F [20C]1.031.021.000.990.970.960.950.930.9214F [10C]1.021.010.990.980.960.950.940.920.9132F [0C]1.011.000.980.970.950.940.930.910.9050F [10C]1.000.990.970.960.950.930.910.900.8859F [15C]1.000.990.970.960.940.930.920.900.8868F [20C]1.000.980.970.950.940.930.910.900.8886F [30C]0.990.970.960.940.930.920.900.890.88104F [40C]0.980.960.950.940.920.910.900.880.87123F [50C]0.970.960.940.930.920.900.890.880.86Locate temperature and elevation on chart aboveTo get correct main jet and idle jet size, multiply the STOCK jet by the correction factor.Needle positionCorrection FactorJet Needle Position.90 and belowLower needle 2 clip positions from stock setting.91 to .95Lower needle 1 clip position1.03 and aboveRaise needle 1 clip position
I have a 06 yfz 450 with a Yoshimura full exaust and a velocity intake what jet size is recommended?
Calvin G on Dec 17, 2016
BEST ANSWER: Hard to say without knowing where you live (weather, altitude, etc). 168 or 170 would be a good starting point.
Have a 06 yfz 450 with full Yoshimura exaust and a velocity intake what jet size is recommended?
A shopper on Dec 17, 2016
BEST ANSWER: I would call Yoshima and tell them what you have. they should be able to suggest a starting point larger than stock
Standard trial and error till you get the right jet for your riding style. i.e. get on your bike warmed up; get into 2nd or 3rd gear and open the trottle (full open) for about 5-10 seconds; immediately hit the kill switch; pull the spark plug and see what color it is; white= too lean/bigger jet needed, sooty black= too rich/smaller jet needed; golden brown is just right/correct main jet. Hope this helps
What main and pilot jet do I need in my 2003 400ex? Specs: UNI air filter (usually run the box cracked open), LexxMXe pipe with race tip, and I usually ride altitude around 1000ft in Minnesota. Stock jets are 148 main and 38 pilot. Thanks a ton!
A shopper on Oct 31, 2017
Pro X 99101-357 Series Keihin Hex Main Jet
Pro X 99101-357 Series Keihin Hex Main Jet
Pro X N424-26 Series Keihin Pilot Jet
Pro X N424-26 Series Keihin Pilot Jet
BEST ANSWER: There isn’t a set jet size for all applications. It’s a trial and error determination. Buy the next next 3 sizes up for both and try each one to see. Will have to move up in set side for sure. Also adjust fuel/air screw. Needle position.
Any way to get this jet in 122 size? That's what pro circuit calls for on my bike.
A shopper on Mar 17, 2017
BEST ANSWER: I looked into this and unfortunately we do not have a size 122 in the Pro X brand but we do have two options in the Keihin brand. Part number 1272270027 and part number 1493570036.
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