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Wiseco Top And Bottom End Kit - 4-Stroke

$435.97 - $674.97
$354.99 - $548.99
4.80 out of 5 stars

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Wiseco Top And Bottom End Kit - 4-Stroke
Wiseco Top And Bottom End Kit - 4-Stroke
  • Description
  • Reviews (4)
  • Q&A (10)
  • Fitment

The MotoSport.com Wiseco Top And Bottom End Kit - 4-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.

4.8 out of 5 stars (4)
4.8 out of 5 stars
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1-4 of 4
Overall 5 out of 5 stars
Ease of Installation
Verified Purchaser

Went together very easy and made good power. Raced with it once and no problems.

Overall 5 out of 5 stars
Ease of Installation
Verified Purchaser
Location: TEXAS
PERFECT FIT Performance upgrade!

this complete kit is perfect, everything you need, and fits perfect, need a new bottom end, if so this is all you need!! BONUS ITS MUCH CHEEPER THAN OEM


Overall 5 out of 5 stars
Ease of Installation
Verified Purchaser
Location: Pittsburgh, Pa
Excellent product

excellent fit and finish, always a good product from wiseco.....

Overall 5 out of 5 stars
Ease of Installation
Location: Gladstone, OR

this was a great kit for the price, installed and bike runs great..

1-4 of 4
Total Questions (10)
Questions with answers:
Questions without answers:
zackry Location: Moncks Corner, SC 29461, USA
1-10 of 10
Fmextreme 29 days ago
Hello, tell me what is included in the kit KX 250F 2006?
Expert MotoSport Staff
29 days ago
The kit would include the following for your 2006 Kawasaki KX250F.

Complete 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 - Exhaust Gasket
1 - Cam Chain Tensioner O-Ring
4 - Valve Stem Seals

Wiseco Pro-Lite Piston kit includes:
piston, rings, pins and circlips.
Honda42 3 months 1 day ago
what bearings come with the kit? I see the 2 main bearings but it seems like there are 2 roller bearings and I believe my 2006 Honda crf 250r has a main ball bearing and a main roller bearing.
MotoSport Staff Expert
2 months 27 days ago
The Wiseco bottom end (WPC143) portion of this kit for your 2006 Honda CRF250R would include the following:

B1086 - Crank Pin Bearing- 30 x 38 x 17.8mm KUZ
B5052 - Main Bearing - 30 x 72 x 16mm
B5056 - Main Bearing - 39 x 58 x 16mm
Crankshaft Accessories
W6451 - Crank Pin- 30 X 13 X 53mm
WB1001 - Btm End Gasket Kit-'04-09 Hon CRF250R/X
rider435 Over 8 months ago
Does it come with all the gasket?
Expert MotoSport Staff
Over 8 months ago
Yes it comes with a top and bottom end gasket kit.
SStacy42 Over 10 months ago Location: Pima, AZ 85543, USA
Should I or no?
Should I get this for my 2012 crf 150r or no? It has 80+ hours of riding and about 50 of it is high rev riding on tracks and trails. It seems fine but I feel like I'm topping the motor out when I ride and I'd rather do this then let it burn out.
Top 1 Contributor
Over 10 months ago
Unfortunately we at Motosport.com are not able to give you repair advice. We highly suggest that you purchase an OEM service manual for your machine and refer to it to answer your repair questions. If you need more assistance, please consult a local repair shop to further assist you in your repairs. If you need parts to assist in your repairs, we are happy to assist you with your parts order.
Matt Over 12 months ago Location: Brisbane QLD, Australia
Will 03 wrf250 full engine rebuild kit fit my wrf250 02 model?
MotoSport Staff Expert
Over 12 months ago
No, this kit will not work on the 2002 WR250F. The 02 has a different crank than the 03.
zackry 1 year 1 month ago Location: Moncks Corner, SC 29461, USA
Does the cam chain tensioner gasket and all other gaskets come included in this kit? I own a 2008 Yamaha YZ450F..?
Top 50 Contributor Top 1 Contributor
1 year 1 month ago
The Wiseco Top and Bottom end kit for your 2008 YZ450F will come with a complete bottom end kit and top end gasket kit. The gasket kit will include for that bike:

1 - Head Gasket
1 - Base Gasket
1 - Exhaust Gasket
1 - Cam Chain Tensioner Gasket
2 - Exhaust Valve Stem Seals
3 - Intake Valve Stem Seals
6 - Oil Line Washers
1 - Head Drain Washer
zackry 1 year 2 months ago Location: Moncks Corner, SC 29461, USA
What are all of the gaskets included?
MotoSport Staff Expert
1 year 2 months ago
The specific gaskets varies depending on the model of your bike but the kit includes complete bottom end gasket kit and complete top end gasket kit.
austin701 1 year 3 months ago
This does have the high compression piston with it correct?
MotoSport Staff Top 1 Contributor Expert
1 year 3 months ago
No, the piston in this kit will have the same compression ratio as your stock (OEM) piston. You can find the available high compression pistons here: http://www.motosport.com/dirtbike/search?textsearch=high+compression+piston&ride=clear
hondarider2 1 year 8 months ago Location: De Soto, IA, USA
Is this a good quality kit?
Is this kit just as good if not better than the oem honda kits?
Expert MotoSport Staff
1 year 8 months ago Location: Portland, OR, USA
Yes, all the components in the Wiseco Kit would be as good of quality as the OEM components if not better.
Top 1000 Contributor
Matt 2 years 7 months ago
Does this include the bottom end gaskets as well?
Only shows the top end gasket kit so I'm assuming that I'll need to purchase the bottom end gasket kit separately?
MotoSport Staff
2 years 7 months ago Location: Portland, OR, USA
For your 2007 Suzuki RMZ450, this top and bottom end kit comes with everything necessary to complete the job. It will come with the bottom end gasket kit.
1 year 8 months ago
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