Pro X Piston Kit

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Pro X Piston Kit
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Pro X Piston Kit

Our Price: $24.00$165.99

MSRP: $51.47 - $232.39 - You save up to $66.40 (29% off)

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Additional Videos

Pro X 4 Stroke Piston

Pro X 2 Stroke Piston

How To - Hone A Cylinder

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

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
128 Reviews
5 Stars
4 Stars
3 Stars
2 Stars
1 Stars
95
17
7
2
7
Value
4.8 / 5
Durability
4.6 / 5
Fitment
4.8 / 5
Performance
4.8 / 5
Recommend it?
Yes (49)
No (1)
Value
5 / 5
Durability
5 / 5
Fitment
5 / 5
Performance
5 / 5
Recommend it?
Yes
2015 KX250F
This kit does not come with a wrist pin, at least mine didn't. Other than that I think it's the way to go. Always have run wiseco, heard some stories of those failing in the kxf250.
January 29, 2018
Raleigh, NC, US
Age: 15-24
Purchased
2 months ago
Gender:
Male
Weight:
131 - 160 lbs.
Height:
5'7 - 5'9
Value
5 / 5
Durability
5 / 5
Fitment
5 / 5
Performance
5 / 5
Recommend it?
Yes
pro-x piston kit
great product ,very high quality , perfect fit, would recommend as an oem replacement
January 23, 2018
IRVINE, KY, US
Age: 45-64
Purchased
5 months ago
Gender:
Male
Weight:
101 - 130 lbs.
Height:
5'7 - 5'9
Value
5 / 5
Durability
5 / 5
Fitment
5 / 5
Performance
5 / 5
Recommend it?
Yes
GREAT PISTON FOR MONEY!
I put over 40 hours on one of these pistons and never had an issue. Great price compared to others, fits prefect.

-m-2013 KTM 65 SX--
January 4, 2018
NORTHPORT, FL, US
Age: 25-44
Purchased
7 months ago
Gender:
Male
Weight:
191 - 220 lbs.
Height:
6'1 - 6'3
Value
5 / 5
Durability
5 / 5
Fitment
5 / 5
Performance
5 / 5
Recommend it?
Yes
Awesome
Shipping was fast thank you!
January 4, 2018
Chadds ford, PA, US
Purchased
2 months ago
Value
5 / 5
Durability
5 / 5
Fitment
5 / 5
Performance
5 / 5
Recommend it?
Yes
Piston
I have used pro x for years an never had a problem
December 22, 2017
Weeksbury, KY, US
Age: 25-44
Purchased
2 months ago
Gender:
Male
Weight:
161 - 190 lbs.
Height:
5'10 - 6'0
Value
5 / 5
Durability
5 / 5
Fitment
5 / 5
Performance
5 / 5
Recommend it?
Yes
Good product
Can never go wrong with pro x, it's just as good as wiseco, for a slightly cheaper price.
December 1, 2017
Norwalk, CA, US
Age: 25-44
Purchased
3 months ago
Gender:
Male
Weight:
221 - 250 lbs.
Height:
5'7 - 5'9
Value
5 / 5
Durability
5 / 5
Fitment
5 / 5
Performance
5 / 5
Recommend it?
Yes
quality
I have never had a problem, and always a perfect fit
November 18, 2017
Partlow, VA, US
Purchased
9 months ago
Value
5 / 5
Durability
4 / 5
Fitment
5 / 5
Performance
5 / 5
Recommend it?
Yes
Right Price Right performance
Ive ordered prox parts numerous times theyre always a perfect fit and perform equal or better than stock replacement parts for a fraction of the cost

-m-2015 KTM 250 XC--
October 23, 2017
alexandria, LA, US
Age: 25-44
Purchased
4 months ago
Gender:
Male
Weight:
191 - 220 lbs.
Height:
5'7 - 5'9
Recommend it?
Yes
All good.
Piston kit was good. Everything fit and assembled well. Only minor issue was that I inadvertently damaged the oil scraper ring spacer and finding a replacement Riken (brand that comes with kit) set of rings, without the buying the entire piston kit, was difficult.
October 18, 2017
Calgary, AB, CA
Purchased
4 months ago
Value
5 / 5
Durability
5 / 5
Fitment
5 / 5
Performance
5 / 5
Recommend it?
Yes
Hard to find,works great
My bike model was only made for 2 years. Some things are hard to find for it. Rocky Mountain was the only place I could find an aftermarket rebuild kit for this bike. (other than the dealer ordering me one for double the price) !

-m-2009 KTM 400 XC-W--
October 17, 2017
Grove City, OH, US
Age: 45-64
Purchased
12 months ago
Gender:
Male
Weight:
221 - 250 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 14 questions Browse 14 questions and 26 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.
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
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.
How do I know if I need new piston?
Richard M on Feb 11, 2018
BEST ANSWER: 1.Pitting/damage to top of piston, 2.scoring/gouging/damage to sides , 3.mics out of bore tolerance, 4.sleeving or overboring cylinder
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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