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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
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Pro X 99101-357 Series Keihin Hex Main Jet

Our Price: $2.24

MSRP: $2.60 - You save up to $0.36 (14% off)

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Details

  • 99101-357 Style.
  • High quality aftermarket jets for Keihin carburetors.
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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
189 Reviews
5 Stars
4 Stars
3 Stars
2 Stars
1 Star
172
13
3
0
1
Value
5.0 / 5
Performance
5.0 / 5
Recommend it?
Yes (72)
No (1)
Value
5 / 5
Performance
5 / 5
Recommend it?
Yes
Brapppp!
My crf450 works great now at higher elevations out here in Utah now
October 16, 2019
SLc , UT, US
Age: 25-44
Purchased
4 months ago
Gender:
Male
Weight:
161 - 190 lbs.
Height:
6'1 - 6'3
Value
5 / 5
Performance
5 / 5
Recommend it?
Yes
Great parts
Good quality parts and would recommend when tuning bike for your conditions you ride in. Great fitment and just like oem.
October 1, 2019
Elizabethville , PA, US
Age: 25-44
Purchased
2 months ago
Gender:
Male
Weight:
191 - 220 lbs.
Height:
6'1 - 6'3
Value
5 / 5
Performance
5 / 5
Recommend it?
Yes
Correct Jetting
One must have the correct jetting for all seasons. the only way you can do this is to have a selection of jet sizes that allow you to go up or down to correct jetting, for altitude or temp.

-m-2018 BETA 300 Xtrainer--
September 10, 2019
Monroe, UT, US
Age: 65+
Purchased
2 months ago
Gender:
Male
Weight:
221 - 250 lbs.
Height:
5'7 - 5'9
Value
5 / 5
Performance
5 / 5
Recommend it?
Yes
Pro x quality
Great product and very affordable. I highly recommend
September 5, 2019
Cedar springs, MI, US
Age: 25-44
Purchased
10 months ago
Gender:
Male
Value
5 / 5
Performance
5 / 5
Recommend it?
Yes
Perfect price
Along with ordering mulitple pilot jets I ordered multiple mains for my 450 cheap cost and great to keep as spares
August 26, 2019
Indian Springs, NV, US
Age: 25-44
Purchased
3 months ago
Gender:
Male
Weight:
221 - 250 lbs.
Height:
6'1 - 6'3
Value
5 / 5
Performance
5 / 5
Recommend it?
Yes
Fit perfectly
Perfect fit and performance was exactly what I expected when needing to properly jet the carb.

-m-2008 HONDA CRF230F--
August 8, 2019
virginia beach, VA, US
Age: 25-44
Purchased
4 months ago
Gender:
Male
Weight:
161 - 190 lbs.
Height:
6'1 - 6'3
Value
4 / 5
Performance
4 / 5
Recommend it?
Yes
Nice to have when rejetting
Nice to have, good value, helps to have on hand when adjusting the settings on the carb.
July 19, 2019
Marvin , SD, US
Age: 25-44
Purchased
6 months ago
Gender:
Male
Weight:
251 - 280 lbs.
Height:
5'10 - 6'0
Value
5 / 5
Performance
5 / 5
Recommend it?
Yes
fixed my jetting
This jet fixed my lean jetting. Worked great. Happy with it so far
May 29, 2019
ARNOLDSVILLE, GA, US
Purchased
6 months ago
Value
5 / 5
Performance
5 / 5
Recommend it?
Yes
Best stuff around
Great jets and fast shipping

-m-1996 HONDA CR250R--
May 14, 2019
Montgomery , IL, US
Age: 45-64
Purchased
6 months ago
Gender:
Male
Weight:
191 - 220 lbs.
Height:
5'10 - 6'0
Value
5 / 5
Performance
5 / 5
Recommend it?
Yes
BRAAAAAAPPPPPP
It’s a very tiny piece of metal with a very important function

-m-2018 HONDA CRF150R Expert--
May 10, 2019
Bababooey, 5 clicks from da nang River , AF
Age: 65+
Purchased
8 months ago
Gender:
Male
Weight:
>281 lbs.
Height:
<5'0
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 13 questions Browse 13 questions and 23 answers
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.
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
looking for some support on my Suzuki rm250 carb keihin pwk 37E1 KHP i have low end that sputters on 1/4 throttle ,just applied new jets low at 50 hi jet 170 float check out good parallel with casting line , air screw turned out 1 full turn ,can anyone shed some light on the low end spuddering ?
Michael G on Apr 1, 2018
BEST ANSWER: I would try do go down a size on the pilot jet. They say the pilot only controls up to 1/3 throttle but personally I would do that first. Second would be a needle adjustment but one notch on the clip will have a larger impact than going down a size on the pilot which is why I suggest the pilot first. This is assuming your bike is sputtering rich. Make sure of that first, if you were lean it would be more of a hesitation than sputtering so just be sure of that. I never had a RM so I’m not sure of base line jetting but I did do my fair share of jetting. Remember, only make one change at a time and test it at full operational temperature before making another change. Be sure to have a clean air filter as well, that would be a problem itself. Good luck.
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.
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
hi I have a crf 150rb with a fmf power core 4 and a 159 big bore do you know what new jets I need? thx
Hollie A on Sep 3, 2019
BEST ANSWER: Jetting is going to change depending on the aftermarket parts you have on your machine, the elevation and temperature you ride in. There in not a specific guide that will give you the exact jets needed. I would suggest ordering a few and testing them.
Need the suggested jet size for 2012 CRF150F riding at elevations around 7000-8000 ft? (stock is 95)
kevin b on Aug 21, 2019
BEST ANSWER: We do not have jetting recommendations, I suggest buying a couple different sizes and test and tune for the best results.
I have a 2009 ktm 105sx. It’s been a disaster and I am fouling plugs and it runs then doesn’t run. What jets are recommended as a place to
Start? I am at sea level and around 60-80degrees f temp
Marina A on Aug 7, 2019
BEST ANSWER: I pulled the KTM dealer site and show stock jetting is 55 idle jet (54531607055), Starter Jet 85 (54831051085) and Main Jet 200 (54531623200).

I would suggest ordering: JD Jetting Jet Kit Fits: 2009 KTM 125 SX Part# 1112690013 | Mfg Part# JDKH01. The JD jetting kit states: Developed and tested from sea level to 12000ft elevation.
Does this jet fit a 2005 Honda TRX450r?
A shopper on Mar 17, 2019
BEST ANSWER: Yes
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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