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Vertex Piston Kit Standard

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Vertex Piston Kit Standard
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Vertex Piston Kit Standard

134315

Our Price: $47.25 – $188.96

MSRP: $52.50 - $209.95 - You save up to $20.99 (10% off)

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Vertex Pistons Review

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Vertex Pistons Review

Details

  • The Vertex Piston Kit includes, piston, rings, wrist pin, and circlips.
  • Standard pistons and components are OEM replacements.
  • All pistons are heat treated with a T-5 or T-6 hardening and tempering cycle.
WARNING: Cancer and Reproductive Harm - www.P65Warnings.ca.gov

Vertex Piston Kit Standard Reviews

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4.7 / 5.0
172 Reviews
5 Stars
4 Stars
3 Stars
2 Stars
1 Star
141
22
3
1
5
Value
4.7 / 5
Durability
4.8 / 5
Fitment
4.8 / 5
Performance
4.8 / 5
Recommend it?
Yes (116)
No (3)
Value
5 / 5
Durability
5 / 5
Fitment
5 / 5
Performance
5 / 5
Recommend it?
Yes
Very impressed
I am a precision machinist and this is one of the best-looking Pistons I've ever seen. Can't wait to keep ordering this brand
March 20, 2020
Pittsburgh, PA, US
Age: 25-44
Purchased
 3 weeks ago
Gender:
Male
Weight:
191 - 220 lbs.
Height:
5'10 - 6'0
Value
4 / 5
Durability
4 / 5
Fitment
4 / 5
Performance
4 / 5
Recommend it?
Yes
Top end rebuild
Bougth this piston for a top end rebuild on my bike sent cylinder off to millennium technologies to get renickle plated to assure a good factory spec cylinder to install this piston

-m-2011 KTM 450 XC-W--
March 12, 2020
lenoir nc, NC, US
Age: 25-44
Purchased
 3 weeks ago
Gender:
Male
Weight:
191 - 220 lbs.
Height:
5'7 - 5'9
Value
5 / 5
Durability
5 / 5
Fitment
5 / 5
Recommend it?
Yes
Vertex Piston kit
Great value kit. Highly recommend this kit that comes with parts needed to change the piston.
March 9, 2020
Callensburg, PA, US
Age: 15-24
Purchased
 8 months ago
Gender:
Male
Weight:
101 - 130 lbs.
Height:
5'4 - 5'6
Value
4 / 5
Durability
4 / 5
Fitment
5 / 5
Performance
5 / 5
Recommend it?
Yes
Same as oem
I prefer to run OEM, this product is basically OEM at a cheaper cost.
February 5, 2020
vancouver, WA, US
Age: 25-44
Purchased
 2 months ago
Gender:
Male
Weight:
191 - 220 lbs.
Height:
5'10 - 6'0
Value
5 / 5
Durability
5 / 5
Fitment
5 / 5
Performance
5 / 5
Recommend it?
Yes
Verrex Piston
Everything was top quality and fit without any issues.
February 1, 2020
Meridian, ID, US
Age: 45-64
Purchased
 2 months ago
Gender:
Male
Value
5 / 5
Durability
5 / 5
Fitment
5 / 5
Performance
5 / 5
Recommend it?
Yes
Great product
This is a great product buy some extra circlips they are very stiff. Make sure to get opening in clip opposite of opening piston. Great product the only piston we used in yz85 and my boy raced 54 times in 2019 on 2 top ends
January 13, 2020
Frederic, MI, US
Age: 25-44
Purchased
 1 year 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
Great product
This is a great product buy some extra circlips they are very stiff. Make sure to get opening in clip opposite of opening piston. Great product the only piston we used in yz85 and my boy raced 54 times in 2019 on 2 top ends
January 13, 2020
Frederic, MI, US
Age: 25-44
Purchased
 1 year 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
Great product
This is a great product buy some extra circlips they are very stiff. Make sure to get opening in clip opposite of opening piston. Great product the only piston we used in yz85 and my boy raced 54 times in 2019 on 2 top ends
January 13, 2020
Frederic, MI, US
Age: 25-44
Purchased
 1 year 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
Rm65 piston kit
Been a good piston and has lasting more than 30hrs. Good right out the box with little break in time needed being a cast piston
December 14, 2019
Concord , NC, US
Purchased
 1 year ago
Gender:
Male
Value
5 / 5
Durability
5 / 5
Fitment
5 / 5
Performance
5 / 5
Recommend it?
Yes
I've had good luck so far
Vertex offers a cylinder specific size (A or B), and they're a supplier for some OEs. That was enough to convince me to give them a try. I've got about 20 hours on it so far, and it seems to be working great. I plan to get Vertex again for the next topend.

-m-2017 YAMAHA YZ250--
November 25, 2019
Carrollton, TX, US
Age: 25-44
Purchased
 1 year ago
Gender:
Male
Show more
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Start typing your question and we'll check if it was already asked and answered. Learn More
Browse 40 questions Browse 40 questions and 107 answers
I'm in search of the "d" size piston kit by vertex, can I find it here?
cody w on Oct 27, 2016
BEST ANSWER: Nearly all of the Vertex pistons we carry are either "A" or "B" sized pistons. But if you can provide the machine you're purchasing for, I'll check to see if we may have the "D" piston.
when should I replace the top end on my 2013 ktm 150 xc. I am a amatuer trail rider and have 55 hours on the engine? Thanks for any advice and knowledge concerning this question.
Jon S on Nov 10, 2016
BEST ANSWER: We race so we replace it with no more than 20 hours on it. You may be able to go longer sick you're on a 150 and trail riding, but it is a lot cheaper to replace the top end than having to have your cylinder replated.
Does it come with everything or will i have to buy something's separate?
A shopper on Dec 17, 2016
BEST ANSWER: You will need a wrist pin bearing and top end gasket kit
Cometic Top End Gasket Set
Cometic Top End Gasket Set
Wiseco Piston Wristpin Bearing
Wiseco Piston Wristpin Bearing
Does this kit come with wrist pin bearing?
roger m on Sep 7, 2016
BEST ANSWER: Roger, you will have to purchase the bearing separately. It comes with piston, piston ring, wrist pin and circlips.
Will this still fit if ive had my cylinder honed? Ktm 350sxf 2014
kieran b on Feb 28, 2017
BEST ANSWER: Honed cylinders should be the same size as before,boring a cylinder is what changes piston diameter. Be careful when honing a plated cylinder as you just want to remove the glaze on the cylinder wall ,DO NOT DAMAGE THE NICKEL COATING. A simple cleanup can be accomplished by rolling up some magazines with a full piece of wet/dry sandpaper (use wet) 400 grit .just make a few gentle ,rotational passes thru the bore .Make sure you clean up all residue .Rocky MT has a nice nylon honing brush also. The plating in your cylinder is critical and expensive to replace, so be gentle.
Is this the "B" piston or equal to KTM Group 2 Piston? KTM recommends Group 2 or "B" piston for bikes with over 50 hours on them
MONTY C on Aug 22, 2016
BEST ANSWER: We do not carry the C Piston. According to Vertex Piston C is Part #23656C. Compression Ratio (x:y): 13.5:1, Cylinder Diameter (mm): 90.00, Displacement (cc): 366.00, Piston Diameter (mm): 89.98, Size Over Standard: 2
what should the compression be reading on a 2013 KTM 150 XC? I am having trouble locating this info without a owners manual.
Jon S on Mar 7, 2017
BEST ANSWER: Compression readings are variable based on the tool being used, the method used, and the various tolerances of the top end parts. If you could find a reference it would be a range like 130-160 psi so it isn't all that much help. The best thing to do is to take a compression reading when you rebuild the top end using your own tools and method that you can repeat so you have a baseline for checking the health of your top end. The best reading will be when the engine is at operating temperature and after there are a couple hours on a new piston and rings. It gives them time to seat. There are plenty of youtube videos to help.
Is the standard vertex piston forged or cast?
Eric B on May 5, 2017
BEST ANSWER: FORGEG
Is this forged or cast?
Connor M on Jun 3, 2019
BEST ANSWER: Vertex pistons are cast. Same as oem pistons. If you want a forged piston you would get a Wiesco.
Is this the size 1 or 2 for ktm pistons? I need size 2 because not a new cylinder
A shopper on Mar 30, 2019
BEST ANSWER: Not sure about size 1 or 2, but this worked great as a replacement position for rebuilding the top end on my 2008 ktm 300 xc.
I have a question about this Vertex piston kit.
I have a 2015 KTM 200 XC-W with 180 hours and I would like to know what piston size I should get?

Thanks!
Arthur P on Oct 18, 2018
BEST ANSWER: With that many hours in the bike it may be time to have the cylinder recoated, after a new nickasil coating is done it is honed back to the original bore size and you would just buy the Oem size
I have a 2007 CR 250, is this piston coated? Also, is this piston a double or single ring?
DOUG B on Oct 9, 2018
BEST ANSWER: I purchased for 2014 TC 125cc two-stroke Husky and it was dual ring. Look at your owners manual to see what your ring count is. This top end kit came with factory replacement--so whatever the factory installed that's what it came with. I do not know if it was coated.
Is the Piston forged or cast?
shane d on Feb 24, 2019
BEST ANSWER: Hello Shane the Vertex pistons we have bought have been cast for our 2 strokes. I hope this helps
2009 KTM 65SX, need new piston & rings / top end kit, the cylinder bore measures 45.048, need a piston and ring size recommendation? We do not use race fuel, mostly pump fuel, so I don't think I need a super high compression piston.
D D on Feb 5, 2019
BEST ANSWER: Ther Vertex 44.97 should be fine. Be sure to check the ring gap as well. Compression will not change between standard pistons unless you modify the head . Looks like you’re more concerned with sidewall clearance. You can also run a Weisco piston at 45 mm. Less clearance at start up when cold. The biggest difference is the Weiseco does not grow as much as the vertex when heated. Forged vs cast. I have ran both and did not notice a difference. We currently run the vertex (cost effective) as we do top ends every 25 hours or so. We race off road Harescrambles
Can I order a b or c piston? The only one listed is A
Jonathan C on May 8, 2018
BEST ANSWER: as the standard bore piston unless you re sleeve the cylinder you don't want an oversized one
So my stock vertex piston in my 2014 ktm 300 has a 71.925mm piston, which is an “A” or “1” size piston, the next size “B” or “2” piston is 71.935mm, but the only option here on rmatv is a 71.95mm. That would make this size in between a “c” and “d” piston, which I believe is pretty large, and not ideal for a first time piston change. Is this correct?
michael w on May 3, 2018
BEST ANSWER: Well you are not over thinking this , to me it is important to get the best fit without being too teight , you cannot run on the teigjt side but you can run a hair on the loose side the only two ways to really know, are one buy the piston and measure the fit prior to install , witch always has to be done to know , or go to a good local shop with a inside dial bore Gage , or a safe bet is to pick the middle size then measure the fit with the piston in the cylinder and a feeler gauge , or call 3 brothers racing ktm ask the there opinions, they are good ktm guys there , I hope this helps , but don't put in the large one and not measure you definitely have the minimum piston to skit clearance
Can someone confirm if the vertex piston 23375A fits the ktm300 2017 models ? If so from what time point, as from 2017 on they run a 2mm shorter skirt. I did hear Vertex changed this part number to suit all, but not sure from what point in time, ie old stock of 23375A may be still the slightly longer 2016 back pistons. So any help when this change occured and how to tell when ordering
Matthew K on Mar 27, 2018
BEST ANSWER: According to Vertex there are 3 different pistons for your machine with 72mm cylinder diameter. Piston #1 is #23375a and is 71.94mm. Piston #2 is 23375b and is 71.95mm. Piston #3 23375C and is 71.96 mm. I show all these pistons fit from 2006-2016 for KTM XC and XC-F.
On my Yamaha warrior 350 the Piston looks shorter than the one in the picture is this going to be a problem?
Carter W on Jul 28, 2017
BEST ANSWER: This picture is generic and doesn't necessarily represent the actual product you will receive. If your machine is listed in the drop down menu, it will fit.
Does this standard vertex piston for the 2005 kx 125 have 1 or 2 rings?
Jason K on Apr 5, 2017
BEST ANSWER: Just one
Is the 71.95 piston an A or a B ?
Benjamin H on Mar 21, 2020
BEST ANSWER: I would be happy to look into this for you. What is the year, make and model for your machine?
Is the ring available separate?
Mike A on Feb 27, 2020
BEST ANSWER: I would be happy to look into this for you. What is the year, make and model for your machine?
I don't want to be down my bike long. If I order the stock bore size and discover I need a larger piston is this returnable as long as it isn't installed?
A shopper on Feb 6, 2020
BEST ANSWER: Please feel free to review our return policy at the link listed below.
https://www.rockymountainatvmc.com/Returns
2019 KTM 65sx first time doing top end on this bike. 40 hours on it with no mods to engine. Do I order 44.96 or 44.97?
Nicholas P on Jan 12, 2020
BEST ANSWER: I suggest measuring the inner diameter of your cylinder to get the proper clearance's
The 2018 Husky TC65 piston has two different sizes, how do I know which piston to order? Do I need to Mic the cylinder?
Christopher R on Dec 3, 2019
BEST ANSWER: Suggest measuring the inner diameter of your cylinder, and referencing your owners manual for the correct size.
I have a 2018 Yamaha yz250x with a C stamped cylinder I was wondering if you have available a C vertex piston kit available or if it would be possible for me to get one through Rocky Mountain? Thank you!
Kyle H on Dec 1, 2019
BEST ANSWER: Most of the aftermarket pistons will be a "B" piston. I recommend getting a "C" piston from the OEM schematic under your machine.
What wrist pin bearing is compatable with this? I couldnt find one on the site or my 2002 RM250. The answer below says that the Weisco one wont work.
jon l on Nov 30, 2019
BEST ANSWER: These pistons are manufactured to OEM specs, that includes the wrist pin diameter. I would recommend ordering the OEM Suzuki wrist pin bearing for the best fitment.
What is the difference between this kit and buying the OEM piston for a KTM 250 through the OEM parts tool? The part numbers seem different, but are they?
Robert L on Nov 5, 2019
BEST ANSWER: I would be happy to look into this for you. What is the year and exact model for your machine?
How do I order the wristpin bearing for a 2018 KTM 450SXF? I do not see one anywhere on Rocky Mountain.
James T on Sep 15, 2019
BEST ANSWER: 4 stroke models do not have wrist pin bearings.
Does this piston for a yz250x have a domed top like the oem piston or is it a flat top?
Luke H on Dec 10, 2018
BEST ANSWER: It’s the same as an oem.
Would this fit on a wr 360?
A shopper on Jun 9, 2018
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 2018 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.
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