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

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
138 Reviews
5 Stars
4 Stars
3 Stars
2 Stars
1 Stars
104
17
8
2
7
Value
4.8 / 5
Durability
4.6 / 5
Fitment
4.8 / 5
Performance
4.8 / 5
Recommend it?
Yes (59)
No (1)
Value
5 / 5
Durability
5 / 5
Fitment
5 / 5
Performance
5 / 5
Recommend it?
Yes
Great Product
Ive been running pro x pistons in my bikes for years now and they have never let me down. Top quality piston and in my opinion I think they are much better than other brands out there
June 18, 2018
Akron, OH, US
Age: 15-24
Purchased
1 year ago
Gender:
Male
Value
5 / 5
Durability
5 / 5
Fitment
5 / 5
Performance
5 / 5
Recommend it?
Yes
Running great after 50+ Hrs.
I've had this piston kit on my grizzly for over 50 hours and it still registers about 200 psi compression. Didn't need to adjust the ring gap or anything, it was a straight forward install

-m-2002 YAMAHA GRIZZLY 660 4x4--
June 15, 2018
vancouver, WA, US
Age: 15-24
Purchased
10 months ago
Gender:
Male
Weight:
161 - 190 lbs.
Height:
6'1 - 6'3
Value
5 / 5
Durability
5 / 5
Fitment
5 / 5
Performance
5 / 5
Recommend it?
Yes
Excellent
Been using pro x pistons for years never let me down
June 5, 2018
Cato , NY, US
Age: 25-44
Purchased
2 weeks ago
Gender:
Male
Weight:
191 - 220 lbs.
Height:
6'1 - 6'3
Value
4 / 5
Durability
2 / 5
Fitment
4 / 5
Performance
2 / 5
Recommend it?
Yes
Only a single ring
Single ring piston for the Suzuki RM250. Didn’t last very long.
April 22, 2018
Baordman , OH, US
Age: 45-64
Purchased
1 year ago
Gender:
Male
Value
5 / 5
Durability
5 / 5
Fitment
5 / 5
Performance
5 / 5
Recommend it?
Yes
Found my missing HP!!
I was able to purchase all the parts, tools, and chemicals to do a complete top end rebuild on my 07 yz450f from RMATVMC for less than a 3rd of the cost to have it done at a local shop. Used the RMATVMC video series too! Great product Great price, arrived on time. Would recommend.
April 17, 2018
Denver, CO, US
Purchased
2 months ago
Value
5 / 5
Durability
5 / 5
Fitment
5 / 5
Performance
5 / 5
Recommend it?
Yes
Great OEM replacement
ART brand piston (same as OEM uses), much cheaper than OEM and same quality.
April 10, 2018
Sterling Heights, MI, US
Age: 15-24
Purchased
2 months ago
Gender:
Male
Value
4 / 5
Durability
5 / 5
Fitment
5 / 5
Performance
5 / 5
Recommend it?
Yes
Will buy again from Rocky Mountain atv
Was perfect fit

-m-1999 YAMAHA WARRIOR 350--will buy again been shopping with you guys for years and many more to come always fast shipping and great products
April 8, 2018
New london, OH, US
Age: 25-44
Purchased
2 months ago
Gender:
Male
Weight:
161 - 190 lbs.
Height:
5'7 - 5'9
Value
5 / 5
Durability
5 / 5
Fitment
5 / 5
Performance
5 / 5
Recommend it?
Yes
Best in the West 4less.


-m-2007 KAWASAKI KX250F--
April 6, 2018
Rosenberg, TX, US
Age: 65+
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
Pro-X is always a great option
I've used Pro-X pistons in numerous applications and never had an issue. They are OEM quality at a better price. Highly recommend.

-m-2006 YAMAHA YZ125--
March 23, 2018
DuPont, WA, US
Age: 45-64
Purchased
8 months ago
Gender:
Male
Weight:
131 - 160 lbs.
Value
5 / 5
Durability
5 / 5
Fitment
5 / 5
Performance
5 / 5
Recommend it?
Yes
Would recommend
Fit and finish has always been nice on Pro X pistons for me. I have used lots of there pistons. everything from 250f 450f 250 2 stroke even on down to my jet skis. When it comes time to put a new one in have always been happy with how they look coming out after many hr. Of use
February 27, 2018
Medford, OR, US
Purchased
4 months ago
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 29 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: 1.Pitting/damage to top of piston, 2.scoring/gouging/damage to sides , 3.mics out of bore tolerance, 4.sleeving or overboring cylinder
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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