Pro X Piston Kit - 2-Stroke

Pro X Piston Kit - 2-Stroke
Pro X Piston Kit - 2-Stroke

$86.98 - $187.98
14% Off - Save up to $13.99

Description See Also: 16 Reviews 21 Questions Fitment
Item #CSB000B

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16 Reviews
4.8 out of 5 stars
5 Star   19 4 Star   4 3 Star   0 2 Star   0 1 Star   0
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All Reviews
yz125
New Hampshire, USA
Durability 5/5 Ease of Installation 5/5 Performance 5/5 Power 5/5 Style 5/5
Nice piston

I recently bought this for my 2015 yz 125 and could not be happier. It took me 20min to install and started first kick. Bike sounds great and runs perfect.

WildBill Verified Purchaser Top 500 Contributor
NH
Durability 4/5 Ease of Installation 4/5 Performance 4/5 Power 4/5 Style 4/5
Everything you need!

I purchased this kit to refresh the top end in my 2010 300XCW and it worked great. Installation was simple and power was back to new. It was great to just by the kit and have everything I needed all at once. Gasket kit was top notch and the piston seems to be good for power. We will see how long the kit lasts but initial impression is very good.

JasonH Verified Purchaser
Ease of Installation 5/5 Performance 5/5 Power 5/5
Great Purchase

Bought this kit for my KTM. I like the cometic gaskets and the Pro X piston gets the job done. Bike is running great, overall nice product.

Hunter
Illinois, USA
Durability 4/5 Ease of Installation 5/5 Performance 5/5 Power 5/5 Style 5/5
Rebuild for my cr250r 8 months ago

Alright, i have a 2000 honda cr250r. i blew the top end about 8 months ago. i ordered this Pro x piston kit. fantastic price and durability. i blew it again today, not mad or surprised. i mean 8 months of hard riding? thats crazy. but it gave my bike alot of power. all around a great price if you dont have alot of money to rebuild. i have read other reviews of this kit and people say after 8 months or so to replace the top end. i agree. its a fantastic kit, i would get another one!

Grubb Verified Purchaser
Bloomington, IN, USA
Piston kit

Great service great products, i"ve order alot of parts from motosport and never had a problem with any of them. Fast service and thats a great thing when your a racer . All parts for are bikes are order from motosport

watertreatpete Verified Purchaser
NY
Durability 4/5 Ease of Installation 5/5 Performance 4/5 Power 4/5
Nice piston kit

Gasket set was nice, Good to have everything in one place rather than ordering separate..

Sockethead Verified Purchaser
South Jersey
Good value, good kit

I couldn't get my bike started in years. I knew it was time for a piston. After replacing, my bike started on the second kick after not starting in 8 years. While any piston would of had the same results, this kit was the best value and came with everything needed to put it back together. I like that didn't need to purchase additional items.
Durability remains to be seen but I'm sure it will be fine.

hondaguy Verified Purchaser
pa
Durability 5/5 Ease of Installation 5/5 Performance 5/5 Power 5/5 Style 5/5

excellent replacement piston

Oldman Verified Purchaser
Auburn, CA, USA
Durability 5/5 Ease of Installation 5/5 Performance 5/5 Power 5/5 Style 5/5
OLD BIKER, SCHOOLED ON PRICE & PARTS

I have used Wiseco. I did some reading,
been outta the "pinger" world for 20 years and I am very pleased and somewhat impressed with all that can be said. I like the product, the kit that MOTOSPORT had to offer and if I have to do the top end on a bike like this again I will use this stuff. Not disappointed in any way. I do not think you can wrong IMHO!

Drew566 Verified Purchaser
Minden, NV, USA
Durability 4/5 Ease of Installation 4/5 Performance 4/5 Power 4/5 Style 4/5
Great Kit

Great Kit, comes with everything needed at a great price. Has held up well so far. I would recommend this kit.

MXBeginner Verified Purchaser
Fay NC
Durability 5/5 Ease of Installation 5/5 Performance 5/5 Power 5/5 Style 5/5
Finally....

My sons bike has been bogging out or just plan ol not running... changed the reeds, cleaned the carb, checked the exhaust inside, changed the fuel mix ratio just about everything, but finally I rebuilt the top end and OMG, this bike is so darn fast!! He is actually timid to ride right now, so we figured that it must have been going bad from the time we bought the bike (used). Ths kit fixed it, easy to install, I just got into this type of stuff and I am lovng the ease of moto products, also all gaskets came with this and some simple instructions. Cheaply priced but the results of my son riding again is PRICELESS.

Top end finished
Breaking in the new piston
Frostycold
Paris, ME, USA
Durability 4/5 Ease of Installation 5/5 Performance 4/5 Power 4/5 Style 4/5
Great product

I recently purchased the Pro-X Piston Kit for my 03 kx125 this spring.
It was a very easy install everything fit and went in smooth.
I would recommend this product to anyone looking to rebuild there top end.
good quality, durable and come with a good price. {Thank you Motosport}

Pro X Piston Kit - 2-Stroke
MotoMiner Verified Purchaser
Lumberport, WV, USA
Durability 5/5 Ease of Installation 5/5 Performance 5/5 Power 5/5 Style 5/5
Great top end kit

Easy to install everthing fits well runs great in 96 cr 250

gunjuice Verified Purchaser
Kent, WA, USA
Durability 5/5 Ease of Installation 5/5 Performance 5/5 Power 5/5 Style 5/5
Pro-X Piston Kit - 2-Stroke

this is the best piston kit i have used in my kids Yz 125 way more power

Yamahafourlife
Milford, CT
Durability 4/5 Ease of Installation 4/5 Performance 4/5 Power 4/5 Style 4/5
Glad With My Purchase

I had problems with the top-end in my 2001 yz125. I installed a wiseco piston and soon enough I had no compression. The head cap may have been the problem. Anyway, I installed the Pro-X piston to see what would happen. So far it has held up very well. The bike still starts first kick. Motosport was great with shipping too, as always. These piston kits are inexpensive as well, which is great.

1000000ktm
maui, hawaii
All good

Piston kit worked great

21 Questions
Answered:   20
Not Yet:   1
Bikelifejay602
Location: Menifee, CA, USA
Q: Would this fit my 04 cr250 it says 72.0mm on the side of my cylinder?
1 month 25 days ago
Motormack250
Location: New Jersey
Q: Does this piston work for both cylinder A or B on the 2002 CR250R.?
4 months 23 days ago
I have a 2002 cr250r does this piston work for both cylinder a and b or not. I don't want to waste my money. I love the ask a question feature
MotoSportExpert
Expert MotoSport Staff
4 months 18 days ago
A: ProX 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. Ultimately, the bore should be measured for the best possible results.

The piston in this kit would be a B piston.
01.1323.B

Feel free to give us a call at 888-676-8853 and we would be happy to help you out with your order.

http://www.pro-x.com/wp-content/uploads/2014/03/Piston-Kit-Instructions.pdf

http://www.pro-x.com/wp-content/uploads/2016/01/Dirt_onlinev2.pdf
alex
Q: Gaskets for 1994 Honda cr 125?
Over 11 months ago
Does this come with the gasket for the power valve control compartment on the side of the cylinder? That compartment must be opened to take off the cylinder, so the gasket needs to be replaced.
MotoSportExpert
MotoSport Staff Expert
Over 10 months ago
A: Top End Kit includes:

1 - Head Gasket
1 - Base Gasket
1 - Exhaust Gasket
1 - Intake Reed Gasket to Carb Boot
1 - Right Power Valve Cover Gasket
1 - Left Power Valve Cover Gasket
1 - Upper Power Valve Cover Gasket

Stock Code: C7115
Honda CR125 92-97
Bore Size: 55mm
beginersluck250
Q: Have a different bore size on moter how do i make sure get correct size it is 69 mm the stock is 66?
1 year 10 months ago
MotoSportExpert
Expert MotoSport Staff
1 year 10 months ago
A: This Pro X Piston Kit is available in the Stock bore only. You can find oversized Wiseco pistons here: http://www.motosport.com/wiseco-prolite-piston-kit-2stroke
Feel free to give us a call at 888-676-8853 and we would be happy to help you out with your order.
Joe93
Q: Will this fit my 2000 KX 125 with bore of 53.97?
2 years ago
Will this fit my 2000 KX 125 with bore of 53.97? Are the gaskets included with this just the ones which are shown?
MotoSportExpert
Top 1 Contributor
2 years ago
A: Pro X comes in a A-D sizing for your 2000 KX125:

Size*: Pistonkit:

53.96 mm. 01.4218.A

53.97 mm. 01.4218.B

53.98 mm. 01.4218.C

53.99 mm. 01.4218.D

54.50 mm. 01.4218.050

Please refer to a factory service manual to make sure you get the correct size of piston after measuring your cylinder bore.
Ricks99cr125
Location: Green forest,Arkansas
Q: My 99 Honda cr125.my cylinder is plated and has some lite grove scored places etc.will this piston help to bring cylinder back to smooth/good shape?
2 years 1 month ago
Kinda like honing it or resize cylinder with pro x piston kit
MotoSportExpert
Top 1 Contributor
2 years 1 month ago
A: With a Nikasil plated bore, you cannot just hone or bore it. You have 2 options: repair & re-plate, or sleeve the cylinder.

Either way, you will have to have a machine shop do the work. You can check with Millennium Technologies for repairing the cylinder or with LA Sleeve if you want to sleeve it.
Ali143
Location: Bahrain International Airport (BAH), Muharraq, Bahrain
Q: Hi, I have kx 250 it has wesco piston standard size 66.4, can I replaced with prox piston size 66.37 without rebor the cylinder?
2 years 2 months ago
MotoSportExpert
Expert MotoSport Staff
2 years 2 months ago
A: Yes, this Pro X Piston Kit would fit your stock bore 2007 KX250.
Stoxee
Location: Ararat
Q: I have a 2001 cr125 and the bore says it is 54.5 is that standard?
2 years 5 months ago
MotoSportExpert
Top 1 Contributor
2 years 4 months ago
A: The Stock bore for you 2001 CR125 is listed as 54.00mm. Be sure to measure your cylinder to make sure there is not an oversized piston installed.
Cowboy02
Location: Springfield, MO, USA
Q: Will this fit a 99 cr250? 2 stroke? It doesn't give that choice?
2 years 7 months ago
MotoSportGrantK
Expert Top 1 Contributor MotoSport Staff
2 years 6 months ago
A: Yes, the Pro X Piston Kit - 2-Stroke is available for your 1999 Honda CR250 and you shouldn't have a problem profiling the Make/Year/Model of your bike. If you continue to have problems, please give us a call at 888-676-8853 and we would be happy to help you out with your order.
rm855
Location: Livermore, ME, USA
Q: 2005 rm85 does it have the single or double ring piston?
2 years 9 months ago
MotoSportExpert
MotoSport Staff Expert
2 years 8 months ago
A: This ProX RM85 piston will be a single ring piston.
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