Wiseco Top And Bottom End Kit - 2-Stroke

Wiseco Top And Bottom End Kit - 2-Stroke
Wiseco Top And Bottom End Kit - 2-Stroke

$271.99 - $652.76
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  • Description
  • 16 Reviews
  • 31 Questions
  • Fitment
Description Item #WCO000Y

The MotoSport.com Wiseco Top And Bottom End Kit - 2-Stroke includes one of each of the following components with the following attributes:

Wiseco Pro-Lite Piston:

Important note: This piston is for a stock sized bore. Please measure your cylinder to check clearance before ordering.

Wiseco leads the performance aftermarket by producing the highest quality forged pistons in the U.S.A. Wiseco is unique because they forge all of their own pistons in-house, and produce all of their own forge tooling in the U.S.A. This allows Wiseco to control all aspects of their manufacturing process from raw bar to skirt coating on the finished parts.

Wiseco Pro-Lite motorcycle pistons are forged using the highest quality materials available resulting in a piston that provides excellent performance and durability. The Wiseco Pro-Lite piston features a race-ready dome finish with smooth edges for improved combustion flow. The rings, wrist pin, and circlips are manufactured by Wiseco under their strict quality standards to make sure every piston kit fits correctly, ensuring top performance is achieved.

Pro-Lite Piston features:

  • Much stronger than stock.
  • Tight tolerances for quiet running.
  • More hours with peak performance between piston changes.
  • All Pro-Lite pistons include rings, wrist pin and circlips.

Extreme racing conditions demand the strength and toughness that only forged pistons can offer. Compared to cast pistons, forgings are tougher and more durable, and will stand up to the abuse that high performance motorsport applications require. Most castings are brittle, have no grain structure and tend to fail catastrophically when the material yield strength is exceeded. Forgings have condensed grain that is aligned to the features of the part, which produces higher mechanical properties, and resistance to impact and fatigue. Each forging is designed to optimize the strength-to-weight ratio, and maximize performance.

Wiseco Complete Crank Kit:

Wiseco Powersports crankshafts feature a double-forged connecting rod made from dedicated forgings. The rods maintain superior strength, durability, and dimensional consistency through improved grain flow. Shot peening eliminates residual stress and oil slots are located to maximize lower rod oiling and extend bearing life. Coated bronze thrust washers have a dimpled design to increase oil retention and reduce stress between the connecting rod, washer, and crank web. Double-drilled small ends provide the piston pin with extra lubrication and cooling, reducing distortion of top end due to thermal transfer from the piston.

Wiseco has designed these crankshafts and connecting rods to work together with their pistons to provide the smoothest rotating assembly possible. Having a complete bottom end that is made of 100% forged material will give you the piece of mind that your motor will be able to withstand any abuse within reason.

Complete Crank Kit features:

  • Each kit contains everything you need to complete your rebuild the right way, the first time - crankshaft and connecting rod, all applicable bearings, and complete bottom end gasket kit made to meet or exceed O.E.M.
  • Wiseco connecting rods are double-forged from a dedicated forging and feature shot peening, oil slots, and coated bronze thrust washers.
  • Bottom end gasket kits are made from premium materials, exceeding O.E.M. standards, to provide exceptional seal between critical mating surfaces.
  • Main bearings are manufactured to the highest quality standards; each is case hardened for maximum life and smooth operation at high RPMs.
  • Corrosion-resistant surface treatment to prevent corrosion and pitting over long term use or storage; this will add to the life as well the strength of the assembly.
  • Top end of rod is bushed for oil retention and eliminates pin galling. The bottom end rod bores are case hardened to 58 - 62 RC to optimize bearing running surface.
  • The crank pin bearings are manufactured from the highest quality, hot rolled steel case hardened to 58 - 62 RC to extend the lifetime of the assembly.
  • Caged needle roller bearings to provide the highest possible RPM.

Professional racers as well as weekend riders choose these solid kits to reduce failure rates and take advantage of the horsepower and immediate torque a lightweight bottom end can deliver.

Cometic Top End Gasket Kit:

State-of-the-art gaskets is what Cometic has been doing since its inception in 1989. This comes from their dedication to constructing gaskets for the most demanding race circuits like AMA and NASCAR. Today's lightweight engines are producing more horsepower, higher cylinder pressure, clamp load and extreme temperatures. Cometic's commitment is to provide innovative, quality gaskets while maximizing your engine's power and performance.

Cometic meets the needs of each specific gasket by using materials to match. Even the basic top end gasket kit features different materials for each gasket. The head gasket is constructed from non-asbestos, flexible graphite that is laminated to a stainless steel core. The manifold and base gaskets are constructed from non-asbestos nitride rubber-bound fiber. Cometic also includes copper gaskets where needed.

Cometic designs and builds their gaskets in the U.S.A.

Note: Image is for reference only, actual Kit may vary based on contents and fitment.


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16 Reviews
4.4 out of 5 stars
5 Star   17 4 Star   1 3 Star   0 2 Star   0 1 Star   3
R3Motox
Verified Purchaser
Jamestown, TN 38556, USA
Durability   Ease of Installation   Performance   Power   Style  

Excellent product.

Gottadog
Walnut Creek CA
Durability   Ease of Installation   Performance   Power   Style  
Not even 16 hours on yz250 lower. Crank = Junk

I bought this upper and lower kit. Piston's from Wiesco are always decent. But the crank.. Another story. I have just under 16 hours on the motor. But since the beginning I always had problems with the crank oil seal. The crank went through 3 of them. If I didn't pull the motor and split the cases it would be needing a 4th seal. The bearing to crank tolerance is very poor on the right side. I had excessive noise recently and found the crank simply slid out of that bearing. Bearing still spins smoothly. Just that the crank and bearing tolerance is too big.

I should have bought a Hot Rods crank, and that is exactly what I just did. Motosport did offer to help with the cost substantially and I give them an A+++ rating. Wiesco only warranties their products for 30 days.

I'm a rec rider. Never race. Run 40/1 oil, always on the slightly rich side. Good thing is these two strokes are a breeze to disassemble and build.

yz125
Sears, MI 49679, USA
Durability   Ease of Installation   Performance   Power   Style  
Bad part

just put in on my 2003 yz125 after about 3 tanks of gas one of the plastic spacers on the crank borke (not melted) and seized the bearings and almost trashed the cylinder. the mechanic said it could be bad plastic or built incorectly. i might try the wiesco crank again.

Gottadog
Verified Purchaser
Walnut Creek, CA, USA
Durability   Ease of Installation   Performance   Power   Style  
So far so good

I have yet to run the motor but everything I bought has been within spec and the install into my yz250 was exactly as expected. I followed the procedures in the manual.

So I'll update after I have some time on the motor.

Phiatt
Top 250 Contributor Verified Purchaser
North Carolina
Durability   Ease of Installation   Performance   Power   Style  
Always used Wiesco products, and will continue too

Wiesco has been around for a long time and as long as they continue with their standards to quality, they will still be around for a long time to come. The kit was excellent, all gaskets and seals were included; this is the only way to go with a total overhaul.

bbbb
Verified Purchaser
Durability   Ease of Installation   Performance   Power   Style  
Top and bottom kit

Great product quick shipping

Hammerhead
Verified Purchaser
Mountain City, TN 37683, USA
Durability   Ease of Installation   Performance   Power   Style  
Excellent Transaction

Unbelievably fast shipping!!! Excellent transaction!!! Will recommend company to everyone we know!!

Jake
Verified Purchaser
Durability   Ease of Installation   Performance   Power   Style  
Bad Idea

I put about 2 - 3 hours on this setup and the needle bearing quit on the big end of the connecting rod. I would not recommend anyone buying this kit strictly because the bottom end does not hold up.

Jab1981
Verified Purchaser
Calhoun City, MS 38916, USA
Durability   Ease of Installation   Performance   Power   Style  
Great parts

Great parts very easy to install will buy again iff ever happens again

Jeremy
Durability   Ease of Installation   Performance   Power   Style  
Great

Good product and would consider it again. Thanks motosport.

Jeremy
Portland Oregon
Durability   Ease of Installation   Performance   Power   Style  
Great Product

Got this kit for my sons 65 and it is badass. Also motorsport does a good job at getting it to you on time.

DaveJ
Verified Purchaser
Chattanooga TN
Durability   Ease of Installation   Performance   Power   Style  
Great Product

Contained everything I needed for rebuild.

muggs
Eucha,OK

VanDii
Santa Fe, TX.
One convenient kit!

This came with everything we needed to get the job done. The bike runs again, and it runs fantastic! I expect the forged crank to be a bit stronger as well!
06 YZ250

ManikRider
Corvallis, OR
Wiseco setup FTW

I am very pleased with the quality of this product. Everything fits together like a dream, and you can tell that the build quality is stellar.

AcTim
Washington, DC
It should be a crime the way we steal!!!l

Just make sure you order the right year...got the years mixed up, but they responded fast and shipped right order. After replacing top & bottom end, reed valve, & bigger jet in carb...you know the rest

1-16 of 16

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31 Questions
Answered:   31
Not Yet:   0
Junior
Location: Queens, NY, USA
Q: What is the stock bore for a 1995 cr125?
Over 9 months ago
MotoSportExpert
MotoSport Staff Expert
Over 9 months ago
A: Stock bore on the 1995 Honda CR125 is 54mm.
mggarza
Q: I need bore size for stock honda cr250 year 2000?
Over 9 months ago
MotoSportExpert
Expert MotoSport Staff
Over 9 months ago
A: The "Stock Bore" piston for your 2000 Honda CR250 would be 66.40MM. Also, feel free to give us a call at 888-676-8853 and we would be happy to help you out with your order.
Colita
Location: New York
Q: Top end?
Over 10 months ago
I have a 2002 cr 125 top end was rebuilt before I bought it my bike dies down taking it out of first then picks back up any ideas what's the problem
MotoSportExpert
MotoSport Staff Expert
Over 9 months ago
A: This could be a number of different possible issues. We would need more information to give an accurate answer. Was the bike doing this before the rebuild? What gearing are you running? Jetting? 2-stroke 125s are a top end motor, not much on the bottom so they are naturally going to bog down at low speed low RPMs. Feel free to give us a call at 888-676-8853 and we would be happy to help you out with your order.
tedder410
Q: What size piston would I need for a 1999 cr125?
Over 11 months ago
MotoSportExpert
Expert MotoSport Staff
Over 11 months ago
A: If you have the stock bore cylinder ou would need the "stock bore" piston. 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.
Colt5700
Location: Canada
Q: With a 2000 Kx250, will Wiseco come with everything needed? Like all gaskets and everything?
1 year ago
MotoSportExpert
MotoSport Staff Expert
Over 12 months ago
A: This Wiseco Top And Bottom End Kit comes with everything generally needed to rebuild your bike (carefully inspect all parts for wear, there may be other parts that need to be replaced).

Crank kit Includes crankshaft, main bearings, complete bottom end gasket set, including all seals and gaskets needed for the job.

Top End Gasket Kit includes:
1 - Head Gasket
1 - Base Gasket
1 - Intake Gasket
1 - Right Power Valve Gasket
1 - Front Power Valve Gasket
1 - Resonator Cover Gasket
1 - Power Valve Rod Gasket
1 - Water Inlet Gasket
2 - Exhaust Gasket

Piston kit includes:
piston, rings, pins and circlips
Samyb1995
Location: Worcestershire
Q: Can I buy a ktm 125 exc 1994 top and bottom end rebuild kit?
1 year 1 month ago
MotoSportExpert
Expert MotoSport Staff
1 year 1 month ago
A: Unfortunately we do not have a top and bottom end kit for the 1994 KTM 125EXC. Feel free to give us a call at 888-676-8853 and we would be happy to help you out with your order.
hoscat201
Location: Bulan, KY 41722, USA
Q: How big would the .080 bore piston be for a yz 125 and how far would i need to bore for the piston?
1 year 2 months ago
MotoSportExpert
Expert MotoSport Staff
1 year 2 months ago
A: The .080 piston for your 2000 YZ125 would be 56mm. 2mm over stock.
MotoSportExpert
MotoSport Staff Expert
1 year 2 months ago
A: The .080 piston for your 2000 YZ125 would be 56mm. 2mm over stock. You would want to take your cylinder and the new piston to the machine shop so they can bore it to match the piston.
shannon
Q: Is there a 56 mm piston available for a 134cc?
1 year 2 months ago
MotoSportExpert
MotoSport Staff Expert
1 year 2 months ago
A: If the part is available through one of our suppliers, we would be happy to order it for you. Please contact one of our sales professionals to inquire about special orders and availability.
Dirt Bike / ATV: 1-888-676-8853
dst125
Location: Mobile, AL, USA
Q: Will this come with all seals and bearings needed to rebuild my 03 rm 125?
1 year 5 months ago
MotoSportExpert
Expert MotoSport Staff
1 year 5 months ago
A: Yes the Wiseco Top And Bottom End Kit has everything generally needed for a complete rebuild. However the kit does not come with every bearing in the motor. Some bearing such as transmission bearings, kickstart bearing ect might need to be replaced once you get in there.
Trip
Location: Reno
Q: Does this kit come complete with a bottom end gasket kit or do I have to buy one. Im just making sure I have everything for a 2003 cr125 completmotor?
1 year 11 months ago
MotoSportGrantK
MotoSport Staff Expert Top 1 Contributor
1 year 11 months ago
A: No, this kit will include a top end gasket kit only. If you could give us a call at 888-676-8853 we will gladly get you a complete gasket kit for your 2003 Honda CR125.
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