Pro X Piston Kit

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Pro X Piston Kit
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Pro X Piston Kit

Our Price: $35.15$165.99

MSRP: $51.47 - $188.18 - You save up to $22.19 (12% off)

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Additional Videos

Pro X 4 Stroke Piston

Pro X 2 Stroke Piston

How To - Hone A Cylinder

How To Measure Your Dirt Bike's Piston To Cylinder Wall Clearance

RM YouTube Channel

Details

    If you’re looking for a cast piston that runs like a top and slides like it’s on ice, pick up a Pro X Piston Kit for you bike, UTV, or ATV.

    Pro X pistons are the premier cast piston made from a specialized low-expansion, low-friction aluminum alloy, commonly used by Japanese OEM engine manufacturers to give the piston an incredibly low co-efficient of friction. For you, this translates to a cast piston perfect for 2 strokes and 4 strokes that has the durability of a forged piston but at a much lower cost. Certain models come with a tin-based skirt coating that reduces wear during and after the wear-in process. This black coating also comes in handy during engine servicing since any excess wear to the piston skirt or cylinder wall will be very apparent in the wear patterns of this coating.

    Pro X uses the best materials available along with innovative designs to give you pistons that are tailor made to the unique requirements of your machine. So if you’re worrying about Pro X Piston Kits being a good fit for you, don’t. Pro X has you covered.

    Specs:
  • Kit includes piston, piston rings, wristpin, and circlips
  • Does not include wristpin bearing for 2 strokes
  • High silicon content aluminum alloy piston
  • Some models include tin-based anti-friction skirt coating
WARNING: Cancer and Reproductive Harm - www.P65Warnings.ca.gov

Pro X Piston Kit Reviews

Each review submitted enters you into a
$100 gift card monthly drawing and a
$500 gift card quarterly drawing!
 
4.5 / 5.0
151 Reviews
5 Stars
4 Stars
3 Stars
2 Stars
1 Star
115
19
8
2
7
Value
4.8 / 5
Durability
4.6 / 5
Fitment
4.8 / 5
Performance
4.8 / 5
Recommend it?
Yes (72)
No (1)
Value
5 / 5
Durability
5 / 5
Fitment
5 / 5
Performance
5 / 5
Recommend it?
Yes
Good pistons, great price.
Pro X is who makes most OEM 2 stroke engine components for Japan. Their quality is top notch and I've never had an issue running them.

-m-2004 HONDA CR250R--
October 17, 2018
Fillmore, UT, US
Age: 25-44
Purchased
1 month ago
Gender:
Male
Value
5 / 5
Durability
5 / 5
Fitment
5 / 5
Performance
5 / 5
Recommend it?
Yes
No compliants
Easy to install, instructions were detailed. The bike runs well now.
October 11, 2018
Spanish Fork, UT, US
Purchased
3 weeks ago
Value
5 / 5
Durability
5 / 5
Fitment
5 / 5
Performance
5 / 5
Recommend it?
Yes
Decent piston
Holds up to the abuse of a 125

-m-2005 SUZUKI RM125--
October 2, 2018
Jamestown, IN, US
Age: 15-24
Purchased
1 month ago
Gender:
Male
Weight:
101 - 130 lbs.
Height:
5'7 - 5'9
Value
5 / 5
Durability
4 / 5
Fitment
5 / 5
Performance
5 / 5
Recommend it?
Yes
KTM 50SX
My first time replacing my sons top end on his 50sx. Super happy with this pro X Piston Kit. Couldn't see the difference from the OEM parts
September 19, 2018
Port Orchard, WA, US
Purchased
1 month ago
Value
5 / 5
Durability
5 / 5
Fitment
5 / 5
Performance
5 / 5
Recommend it?
Yes
Got a non running ‘02 yz250f running and went in great
September 12, 2018
Spring, TX, US
Age: 15-24
Purchased
1 month ago
Value
5 / 5
Durability
5 / 5
Fitment
5 / 5
Performance
5 / 5
Recommend it?
Yes
Very good for price
Ive had this piston since I bought my bike, and have put 68 hours on so far, at a track, and it has held up pretty well.

-m-2003 HONDA CR125R--
August 24, 2018
Mira Loma, CA, US
Age: 15-24
Gender:
Male
Weight:
131 - 160 lbs.
Height:
5'10 - 6'0
Value
4 / 5
Durability
4 / 5
Fitment
5 / 5
Performance
5 / 5
Recommend it?
Yes
Great replacement for OEM
Went with the Prox because it is same as OEM for my CR125. Don't forget to order a wrist pin bearing, as this kit doesn't come with one.

-m-2001 HONDA CR125R--
August 7, 2018
lacey, WA, US
Purchased
2 months ago
Value
5 / 5
Durability
5 / 5
Fitment
5 / 5
Performance
5 / 5
Recommend it?
Yes
TAT
I put this piston kit in my 2008 450 EXC-R before I left on the Trans America Trail. I put nearly 7000 miles on this piston/stock cylinder in the last month and a half. The bike is now burning oil and will get another rebuild soon. I will most likely buy this piston kit again. No problems with this product during the trip. Longevity had exceeded my expectations!

-m-2008 KTM 450 EXC-R--
August 5, 2018
Lewisville, NC, US
Purchased
5 months ago
Value
5 / 5
Durability
5 / 5
Fitment
5 / 5
Performance
5 / 5
Recommend it?
Yes
Just installed pro x piston kit in my son's kx 85. Quality finish & fitment. Ring gap was right on, install was easy. Bike started 1st kick had great compression. Then we were off to the races where he placed third overall for his class. Not that it was all the piston but great product, will do it again next rebuild.
July 24, 2018
Laporte, CO, US
Age: 25-44
Purchased
3 months ago
Gender:
Male
Value
5 / 5
Durability
3 / 5
Fitment
5 / 5
Performance
4 / 5
Recommend it?
Yes
Good replacement piston
Good fit,ring gap was correct, casting seemed clean as well.

-m-2002 YAMAHA YZ125--
July 5, 2018
Springtown, TX, US
Age: 25-44
Purchased
3 months ago
Gender:
Male
Weight:
161 - 190 lbs.
Height:
5'7 - 5'9
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 16 questions Browse 16 questions and 30 answers
What is a or b piston kit. Mean for pro-x????
A shopper on Aug 20, 2016
BEST ANSWER: Hey there,

The manufacture measures the bore from the factory and provides a letter to represent the size. For example, "A" would be smallest within the manufactures tolerances and "B" or "C" would be larger sizes. The manufacture will usually stamp the cylinder with the size. The recommendations I received are to go up one letter to account to wear and tear. However, that's not official, just a recommendation that was given to me.
How do I know if I need new piston?
Richard M on Feb 11, 2018
BEST ANSWER: Pistons need to be replaced every 15-20 hours. If your bike starts running bad and jetting doesn’t effect how it runs then you need a new piston.
Is the pro x piston a forged or cast piston?
JOHN D on Dec 25, 2016
BEST ANSWER: This is a cast piston.
I have a rm85 with a locked kick start I'm jus trying to find what could it be ?
shaun w on Aug 22, 2017
BEST ANSWER: If there is metal in the transmission oil you will need to take the right side cover off and see what is stopping the starter lever. if the piston is seized in the cylinder, the top end will need to be removed and repaired as needed.
Does your Pro X Piston Kit come with a Wrist Pin and Wrist Pin Bearing?
Jeremy T on Feb 7, 2018
BEST ANSWER: yes but i recommend purchasing the oem bearing, the difference in quality is clearly visible
I am planning on ordering this kit for my 2000 ktm sx250. This kit doesn't come with the wristpin bearing , correct? Will the specific piston for my bike come with the black coating around the sides or not for my specific bike??
Brian P on Feb 24, 2018
BEST ANSWER: No wrist pin bearing or black coating on the kit for my 250 exc
What to do when blown motor?
Randy G on Dec 14, 2017
BEST ANSWER: If it’s the top end you can have it bored and sleeved, if it’s the bottom end they can be rebuilt but it is time consuming and slightly costly.
What is standard bore size for a 2001 125 yz ?
A shopper on Jun 22, 2017
BEST ANSWER: Stock bore size on yz 125 is 53.94mm. Check ring gap per manual. If it is offered go with a B size since your bike is old you'll have a tighter fit.
will this piston work in a 2013 Husaberg te250?
A shopper on May 28, 2018
BEST ANSWER: Yes, you will just need to enter in your machine in the drop down boxes above the product image.
How come it doesn't give me the options for a kx100 ?
A shopper on Oct 7, 2017
BEST ANSWER: Unfortunately, we do not carry this piston kit for your machine. If you let me know what year your KX100 is I can check our inventory for you.
will this piston for my 2004 suzuki eiger LTF400F?
A shopper on Aug 7, 2017
BEST ANSWER: Unfortunately, we do not carry this piston for this machine.
It is compatible with the motorcycle KTM 250 EXC-F 2013?
Luis V on Apr 20, 2017
BEST ANSWER: To see if this part will fit your machine please enter the make, model, and year into our "Choose a vehicle" drop down boxes found above the product image. If your machine is not listed, we may not carry the right item for your application. If you have a 2017 year model but don't see your machine as an option, please contact a tech via Live Chat or call us at 1-800-336-5437 for assistance.
Is this a "c" piston?
Skip N on Apr 4, 2017
BEST ANSWER: What machine is this for?
Will this work on my Yz85?
A shopper on Dec 26, 2016
BEST ANSWER: To see if this part will fit your machine please enter the make, model, and year into our "Choose a vehicle" drop down boxes found above the product image. If your machine is not listed, we may not carry the right item for your application. If you have a 2017 year model but don't see your machine as an option, please contact a tech via Live Chat or call us at 1-800-336-5437 for assistance.
Does it come with gaskets?
A shopper on Dec 5, 2016
BEST ANSWER: No, gaskets are not included with this kit.
So what is the size of an "A" piston for a 2005 CR 250R ?
I have the stamp of "B" on the cylinder and the piston I ordered/rec is a standard 66.36mm, will this work or do I need to order a different size for "B"?
CHARLES S on Oct 19, 2016
BEST ANSWER: The diameter of the OEM A piston is 65.9mm. This kit should work with your cylinder as long as the ring end gap measurement is correct.
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