Vertex 2-Stroke Piston Kit - Stock Bore

Vertex 2-Stroke Piston Kit - Stock Bore
Vertex 2-Stroke Piston Kit - Stock Bore

$92.40 - $224.61
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Item #VER0008

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44 Reviews
4.5 out of 5 stars
5 Star   38 4 Star   9 3 Star   0 2 Star   1 1 Star   3
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All Reviews
stallion
Missouri, USA
Durability 5/5 Ease of Installation 5/5 Performance 5/5 Power 5/5 Style 5/5
Easy to install and fit like stock

very pleased with these piston kits, I used these on my 2000 kx250 and they worked great so I decided to try them on my new bike too.

Duck5 Verified Purchaser
Weatherford, ok
Durability 5/5 Ease of Installation 5/5 Performance 5/5 Power 5/5 Style 5/5
KTM 65sx

Quality is outstanding, the install went perfectly and the bike runs much better. Ktm uses vertex from the factory, the durability has been outstanding. I highly recommend using this product, the gaskets are very good as well.

Pittcrew Top 500 Contributor Verified Purchaser
Pittsburgh
Durability 5/5 Ease of Installation 5/5 Performance 5/5 Power 5/5 Style 5/5
Great kit.

Used this in a 2011 kx85. It's been through 2 woods series races and is holding up just fine. Every bit as good as any other brands I've used.

Phil
Dayton, OH, USA
Ease of Installation 4/5
Good kit

Parts seems of good quality. I like that the needle bearing it comes with us hot rod. Haven't ridden with it yet so I can't speak on power or reliability. My only complaint is it didn't come with the copper crush washers for the head bolts that my YZ 250 has. I didn't notice untill reassembly. Had to order them separately. Would rather pay more for the kit and have them included. Other than that it went together great.

Loaner Verified Purchaser
San Diego, CA, USA
Durability 5/5 Ease of Installation 5/5 Performance 5/5 Power 5/5 Style 5/5
Easy Top End Package

This gave me everything i needed to swap out the top end on my KTM. What a dream, no running back to the shop for a gasket, or needle bearing. I highly recommend this kit, and the Vertex pistons have lasted for me with no issues.

pmdparts Verified Purchaser
Abbeville, SC 29620, USA
Ease of Installation 5/5 Performance 5/5 Power 5/5 Style 5/5
Nice product--but beware of "A" ,"B", or "C"sizes

Ordered this kit for 2013 KTM 85 sx. Description says "standard bore'" but apparently, KTM produces engines with "A", "B", and "C" bores from the factory. These are just three different size pistons that vary by a fraction of a millimeter and are fit to each motor individually to help account for variance in machining and plating of the bores. The piston I received was a "B" unit and it turns out that our bike was fitted with a "C" piston from the factory. I wish that the item description had spelled this out so that I could have gotten the "c" piston instead, but there was no mention of this in Motosport's description. I installed the "b" unit and I'm sure it will be fine since I will replace it in about 20 hours anyway.

Rider13 Verified Purchaser
Modesto, CA, USA
Durability 1/5 Ease of Installation 4/5 Performance 1/5 Power 4/5 Style 3/5
Faulty product

Shortly after installation of this piston and break in my engine seized. A large chunk of the top of the piston broke off wedging itself between the head and the remaining piston, destroying not only my new piston, but also my cylinder and head.

DirtLife Verified Purchaser
DTown Racer
Durability 4/5 Ease of Installation 4/5 Performance 5/5 Power 5/5 Style 4/5
First Top end rebuild on 85r Honda

Researched rebuild days before part showed up. Made job easy.

1Racing Verified Purchaser
Texas, USA
Durability 5/5 Ease of Installation 5/5 Performance 5/5 Power 5/5 Style 5/5

Great replacement for stock.

Pickle Verified Purchaser
Atlant Ga
Durability 5/5 Ease of Installation 5/5 Performance 5/5 Power 5/5 Style 5/5
Great top end

Never have a problem with this top end in my sons yz-85

speedy Verified Purchaser
Montana, USA
Durability 4/5 Ease of Installation 4/5 Performance 4/5 Power 4/5 Style 3/5
Good kit

everything you need

DirtWarrior
Western PA
Durability 5/5 Ease of Installation 4/5 Performance 5/5 Power 5/5 Style 5/5
2 Stroke Power!

This is a great rebuild kit. Very high quality parts. The only improvement that I think could be made is if Cometic decided to put a paper in their gasket kit that labeled each individual gasket and O-ring. Other than that, fantastic product. Just as good, if not better than Wiseco.

brokendad Verified Purchaser
Edmond, OK
Durability 4/5 Ease of Installation 5/5 Performance 5/5 Power 5/5 Style 3/5
Top End Kit

Restore the power in your bike byu using quality parts!

shnedy Verified Purchaser
Durability 5/5 Ease of Installation 5/5 Performance 5/5 Power 5/5 Style 5/5
Great product vertex piston

Got the piston kit for my cr 125 it had no compression.
After i replaced the piston and ring wow what a difference. Before i changed it i was able to start the bike with my hand. Those days are over .
Great product.

Roosty Verified Purchaser
Salt Lake City, UT, USA
Durability 5/5 Ease of Installation 5/5 Performance 5/5 Power 5/5 Style 5/5
As usual motosport delivers

Love these guys! The vertex piston fit perfectly and the cometic gaskets are working as advertised. In fact, the expansion chamber o-rings fit much tighter than OEM so no more oil spooge from exhaust! Thanks motosport!

Tony Verified Purchaser
Durability 4/5 Ease of Installation 5/5 Performance 4/5 Power 5/5 Style 4/5
Great buy!

I will buy again! Installed on a 97 cr 125 that had a dime size hole in the Piston marked clearly fits factory specifications. Gaskets that come with the kit are way better then the oem paper gasket

yzrippa
Louisiana, USA
Durability 1/5 Ease of Installation 5/5 Performance 2/5 Power 2/5 Style 5/5
DO NOT BUY!!!!

because this piston is not forged its cast which causes weak spots in the piston and after about 8 hours of run time always on a track with races the skirt of the piston blew off and ruined my cylinder and crank.

Zach
Binghamton, NY
Durability 5/5 Ease of Installation 5/5 Performance 5/5 Power 5/5 Style 5/5
Great piston

I decided to do a top end on my cr125 this winter and change it up from my usual Wiseco piston. Now that the snow is melting I can finally get back out and ride and this piston is great in my bike. Would definitely recommend this kit!

Deema00 Verified Purchaser
Napa, CA, USA
Durability 5/5 Ease of Installation 5/5 Performance 5/5 Power 5/5 Style 5/5
03 CR250 Top End Build

Super Stoked on the Vertex Top End Kit. The power is back! It came with everything needed for the rebuild. Installation was easy and a breeze. I recommend this set-up for any CR owner. Quality, Super Quick and Great service. From Motosport to my House to My Bike. couldnt be happier to be back riding.

Deema00
Napa, CA, USA
Durability 5/5 Ease of Installation 5/5 Performance 5/5 Power 5/5 Style 4/5
03 CR250 Top End

Super stoked on the vertex top end kit, the power is back in my 2stroke. The kit came with everything needed to re-do the top end. Straight from Motosport to my house to my bike! Recommend this set-up to any CR owner. Quick, Convenient, and Quality. Everytime.

See 20 More Reviews
36 Questions
Answered:   31
Not Yet:   5
Brad
Location: Varysburg, NY 14167, USA
Q: I bought a new jug for my Kx 85 will this piston fit? It is a moose racing cylinder std?
3 months 3 days ago
Jjohnson
Q: What piston size is this I have a 2009 Ktm 250 xcw?
4 months 8 days ago
2009 Ktm 250xcw
Tomskog
Q: What piston should I choose for a 2014 yz250?
Over 6 months ago
Eric
Q: Is the piston in the 2015 KTM 300 XC kit a B piston?
Over 7 months ago
What is the gasket thickness under the jug? I have been told there should be a .2 and a .4 gasket installed under the jug.
EricL
Q: What is the measurements on this piston?
Over 7 months ago
Is this piston A,B,C or D?
Kurt820
Location: Oklahoma, USA
Q: Is this a single ring piston and what will fit a 2014 kx85 85?
1 year ago
MotoSportExpert
MotoSport Staff Expert
1 year ago
A: Yes. Just be sure to correctly select the Year/Make/Model of your bike before ordering so we can be sure to send you the correct kit for your bike. Also, feel free to give us a call at 888-676-8853 and we would be happy to help you out with your order.
Jesse
Location: Nanticoke, PA
Q: 99 YZ250?
1 year ago
I am currently rebuilding a YZ250 from the ground up, the cylinder has just been re-plated to stock bore of 66.4mm. It's telling me that this is an exact fit for my bike, but I see the piston is listed as 66.35mm. Will this work?
MotoSportExpert
Expert MotoSport Staff
Over 12 months ago
A: Yes the 66.35mm would be correct.
Kelson
Q: Is this the exact stock piston that comes in the bike 2014 ktm 250 sx?
1 year 4 months ago
Loaner
1 year 3 months ago
A: It exactly matched my 11 300xc & 12 250xc, so i bet it is.
Deland
Location: Orangeburg, SC, USA
Q: May I use this piston kit with the Athena cylinder?
1 year 4 months ago
MotoSportExpert
Expert MotoSport Staff
1 year 4 months ago
A: Yes this Vertex 2-Stroke Piston Kit - Stock Bore would work with a stock bore Athena Cylinder.
Dylan22
Location: Georgia, USA
Q: Will a size c fit a 2004 KTM 125sx that has had a stock piston in it?
1 year 8 months ago
I have a 2004 KTM 125sx and I would like to know if there Is a real big difference in piston sizes for this bike. The piston hasn't been changed before I don't think.
MotoSportExpert
MotoSport Staff Expert
1 year 8 months ago
A: Vertex offers A, B, C, D, sizes so that the customer can properly fit each piston to the cylinder. The difference in the sizes is 0.01mm (0.0004") increments with A being the smallest and D the biggest. When a cylinder wears, the customer can choose the next larger piston size to regain the proper factory fitment. If you are just replacing the piston, then you need to first know the bore of the cylinder. This can be done by using a bore gauge to find the diameter or by reading the owner’s manual to find the bore specifications. Ultimately, the bore should be measured for the best possible results. After the diameter is known, then you can pick which size piston will work best in your cylinder. Remember to maintain about a 0.05mm (0.002”) piston to cylinder clearance, depending on application. If you are having a cylinder re-plated, then you will want to choose a piston of the OE bore size (an A or B size is probably best). When you send the piston and cylinder away to get re-plated, the plating facility will match the cylinder bore to piston diameter. If you have a cast iron bore cylinder and you are sending the piston and cylinder off to a machinist to be bored out, then you will want a piston that is oversized from the current diameter. For example: If your current bore is 64.00mm, then you will want to choose a 64.50mm or similar oversized piston. The machinist boring the cylinder will bore and hone the cylinder to match the piston size.
Also, feel free to give us a call at 888-676-8853 and we would be happy to help you out with your order.
1-10 of 36
Fitment
See all bikes that this part fits...
See Fitments
# Part Numbers
Gasket Kit
Product Variant Manufacturer Part #
Vertex 2-Stroke Piston Kit - Stock Bore C3416
Vertex 2-Stroke Piston Kit - Stock Bore C7921
Vertex 2-Stroke Piston Kit - Stock Bore C7859
Vertex 2-Stroke Piston Kit - Stock Bore C7394
Vertex 2-Stroke Piston Kit - Stock Bore C7778
Vertex 2-Stroke Piston Kit - Stock Bore C7337
Vertex 2-Stroke Piston Kit - Stock Bore C7508
Vertex 2-Stroke Piston Kit - Stock Bore C7757
Vertex 2-Stroke Piston Kit - Stock Bore C7120
Vertex 2-Stroke Piston Kit - Stock Bore C7016
Vertex 2-Stroke Piston Kit - Stock Bore C7059
Vertex 2-Stroke Piston Kit - Stock Bore C7113
Vertex 2-Stroke Piston Kit - Stock Bore C7112
Vertex 2-Stroke Piston Kit - Stock Bore C7851
Vertex 2-Stroke Piston Kit - Stock Bore C7136
Vertex 2-Stroke Piston Kit - Stock Bore C7093-EST
Vertex 2-Stroke Piston Kit - Stock Bore C7779
Vertex 2-Stroke Piston Kit - Stock Bore C3085
Vertex 2-Stroke Piston Kit - Stock Bore C7467
Vertex 2-Stroke Piston Kit - Stock Bore C3089
Vertex 2-Stroke Piston Kit - Stock Bore C3099
Vertex 2-Stroke Piston Kit - Stock Bore C7020
Vertex 2-Stroke Piston Kit - Stock Bore C7064
Vertex 2-Stroke Piston Kit - Stock Bore C7855
Vertex 2-Stroke Piston Kit - Stock Bore C7065
Vertex 2-Stroke Piston Kit - Stock Bore C7250
Vertex 2-Stroke Piston Kit - Stock Bore C7123
Vertex 2-Stroke Piston Kit - Stock Bore C7507
Vertex 2-Stroke Piston Kit - Stock Bore C7156
Vertex 2-Stroke Piston Kit - Stock Bore C3211
Vertex 2-Stroke Piston Kit - Stock Bore C7280
Vertex 2-Stroke Piston Kit - Stock Bore C7094
Vertex 2-Stroke Piston Kit - Stock Bore C7505
Vertex 2-Stroke Piston Kit - Stock Bore C7678
Vertex 2-Stroke Piston Kit - Stock Bore C7857
Vertex 2-Stroke Piston Kit - Stock Bore C7181
Vertex 2-Stroke Piston Kit - Stock Bore C7853
Vertex 2-Stroke Piston Kit - Stock Bore C7115
Vertex 2-Stroke Piston Kit - Stock Bore C7936
Vertex 2-Stroke Piston Kit - Stock Bore C7191
Vertex 2-Stroke Piston Kit - Stock Bore C3105
Vertex 2-Stroke Piston Kit - Stock Bore C7015
Vertex 2-Stroke Piston Kit - Stock Bore C7158
Vertex 2-Stroke Piston Kit - Stock Bore C7116
Vertex 2-Stroke Piston Kit - Stock Bore C7399
Vertex 2-Stroke Piston Kit - Stock Bore C7762
Vertex 2-Stroke Piston Kit - Stock Bore C7203
Vertex 2-Stroke Piston Kit - Stock Bore C7088
Vertex 2-Stroke Piston Kit - Stock Bore C7384
Vertex 2-Stroke Piston Kit - Stock Bore C7241
Vertex 2-Stroke Piston Kit - Stock Bore C7117
Vertex 2-Stroke Piston Kit - Stock Bore C7393
Vertex 2-Stroke Piston Kit - Stock Bore C7391
Vertex 2-Stroke Piston Kit - Stock Bore C7764
Vertex 2-Stroke Piston Kit - Stock Bore C7097
Vertex 2-Stroke Piston Kit - Stock Bore C7861
Vertex 2-Stroke Piston Kit - Stock Bore C7285
Vertex 2-Stroke Piston Kit - Stock Bore C7269
Vertex 2-Stroke Piston Kit - Stock Bore C7031
Vertex 2-Stroke Piston Kit - Stock Bore C3096
Vertex 2-Stroke Piston Kit - Stock Bore C7019
Vertex 2-Stroke Piston Kit - Stock Bore C7100
Vertex 2-Stroke Piston Kit - Stock Bore C7089
Vertex 2-Stroke Piston Kit - Stock Bore C7135
Vertex 2-Stroke Piston Kit - Stock Bore C7098
Vertex 2-Stroke Piston Kit - Stock Bore C7155
Vertex 2-Stroke Piston Kit - Stock Bore C7133
Vertex 2-Stroke Piston Kit - Stock Bore C7682
Vertex 2-Stroke Piston Kit - Stock Bore C7333
Vertex 2-Stroke Piston Kit - Stock Bore C7416
Vertex 2-Stroke Piston Kit - Stock Bore C7943
Vertex 2-Stroke Piston Kit - Stock Bore C7386
Vertex 2-Stroke Piston Kit - Stock Bore C7423
Vertex 2-Stroke Piston Kit - Stock Bore C7010
Vertex 2-Stroke Piston Kit - Stock Bore C7456
Vertex 2-Stroke Piston Kit - Stock Bore C7942
Vertex 2-Stroke Piston Kit - Stock Bore C7690
Vertex 2-Stroke Piston Kit - Stock Bore C3222
Vertex 2-Stroke Piston Kit - Stock Bore C7760
Needle Bearing
Product Variant Manufacturer Part #
Vertex 2-Stroke Piston Kit - Stock Bore WB112
Vertex 2-Stroke Piston Kit - Stock Bore WB117
Vertex 2-Stroke Piston Kit - Stock Bore WB119
Vertex 2-Stroke Piston Kit - Stock Bore WB115
Vertex 2-Stroke Piston Kit - Stock Bore WB128
Vertex 2-Stroke Piston Kit - Stock Bore WB111
Vertex 2-Stroke Piston Kit - Stock Bore WB141
Vertex 2-Stroke Piston Kit - Stock Bore WB113
Vertex 2-Stroke Piston Kit - Stock Bore WB110
Vertex 2-Stroke Piston Kit - Stock Bore WB116
Vertex 2-Stroke Piston Kit - Stock Bore WB104
Vertex 2-Stroke Piston Kit - Stock Bore WB118
Vertex 2-Stroke Piston Kit - Stock Bore WB107
Vertex 2-Stroke Piston Kit - Stock Bore WB120
Vertex 2-Stroke Piston Kit - Stock Bore WB108
Vertex 2-Stroke Piston Kit - Stock Bore WB139
Vertex 2-Stroke Piston Kit - Stock Bore WB102
Piston
Product Variant Manufacturer Part #
Stock Bore 22189B
Stock Bore 22685C
Stock Bore 1
Stock Bore 22995B
Stock Bore 22224B
Stock Bore 23140C
Stock Bore 22459B
Stock Bore 22153B
Stock Bore 22540B
Stock Bore 22387B
Stock Bore 23119B
Stock Bore 22581B
Stock Bore 22245B
Stock Bore 22809B
Stock Bore 22649B
Stock Bore 23133B
Stock Bore 22998B
Stock Bore 22447
Stock Bore 22854B
Stock Bore 22860B
Stock Bore 22520B
Stock Bore 22502B
Stock Bore 22154B
Stock Bore 22803B
Stock Bore 22151B
Stock Bore 22498B
Stock Bore 22293B
Stock Bore 22712B
Stock Bore 22541B
Stock Bore 23004B
Stock Bore 23928B
Stock Bore 22244B
Stock Bore 22652B
Stock Bore 22521B
Stock Bore 22386B
Stock Bore 22795B
Stock Bore 22585B
Stock Bore 23124B
Stock Bore 22868B
Stock Bore 22481CD
Stock Bore 22441B
Stock Bore 23430CD
Stock Bore 22806B
Stock Bore 23294B
Stock Bore 22356B
Stock Bore, A Piston 23383A
Stock Bore, B Piston 22584B
Stock Bore, Double Ring 22926B
Stock Bore 22569
Stock Bore 22650B
Stock Bore 22215B
Stock Bore 22909B
Stock Bore 22248B
Stock Bore 23121B
Stock Bore 22442B
Stock Bore 23630B
Stock Bore 22532B
Stock Bore 23375B
Stock Bore 22646B
Stock Bore 22877B
Stock Bore, Single Ring 22925B
Stock Bore 22216B
Stock Bore, A Piston 22584A
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