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2001 KTM 125SX

Wiseco Top And Bottom End Kit - 2-Stroke

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

Product Description

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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1-10 of 18
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Verified Purchaser
Location: Walnut Creek, CA, USA
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.

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Top 1000 Contributor Verified Purchaser
Location: North Carolina
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.

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Verified Purchaser
Top and bottom kit

Great product quick shipping

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Verified Purchaser
Location: Mountain City, TN 37683, USA
Excellent Transaction

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

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Verified Purchaser
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.

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Verified Purchaser
Location: Calhoun City, MS 38916, USA
Great parts

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

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Great

Good product and would consider it again. Thanks motosport.

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Location: Portland Oregon
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.

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Verified Purchaser
Location: Chattanooga TN
Great Product

Contained everything I needed for rebuild.

Overall
Location: Eucha,OK

1-10 of 18
Total Questions (18)
Questions with answers:
  17
Questions without answers:
  1
michaelfornaomi Location: oberon nsw 2787 australia
1-10 of 18
michaelfornaomi 16 days ago Location: oberon nsw 2787 australia
Do you have a 1987 ktm rebuild kit available?
In need of a full rebuild kit 4 a 1987 ktm125 would u have one or do you know where I could get one??
Expert MotoSport Staff
15 days ago Location: Portland, OR, USA
Unfortunately, We would not have any pre-1990 KTM Parts available to us. I would recommend contacting your nearest KTM Motorcycle Dealership.
gary 1 month 16 days ago
Wiseco Top And Bottom End Kit - 2-Stroke. Where do I get spare piston rings for this kit, does OEM fit?
Top 1000 Contributor
1 month 15 days ago Location: North Carolina
I myself wouldn't put an OEM ring on a Wiseco piston. Just get a Wiseco ring for Wiseco piston and so forth. Replacement rings can be found through Motosport; measure your bore first to insure you order the correct size.
MotoSport Staff Expert
23 days ago Location: Portland, OR, USA
Normally the OEM rings will work on Wiseco pistons but we can also order replacement rings for Wiseco pistons. Give us a call at 888-676-8853 and we can get you all set up with the replacement Wiseco Rings for your piston.
Barnard 1 month 24 days ago Location: Thailand/Australia
(K)DX 250 (Japanese import version)?
Have a '93 DX250F (SR) model which I did the big end. This model had the longer stroke hence spares are hard to come by. The KDX 250 '91to'94 gaskets(complete set)and crank bearing set (complete) match the DX250F (so I guess crank housings very very similar) and was wondering if I put a KDX or KX 250 con rod in the crank to replace the original along with a KDX/KX barrel and piston to match as I would assume the barrel would be a little shorter than the original. Have you any previous experience with a spares compatibility question like this one!
Dave 2 months 19 days ago
What else will I need?
I just lost the bearing on the bottom of the connecting rod. Will this kit give me everything I need when I split the case to get this thing back together
Top 1000 Contributor
2 months 18 days ago Location: North Carolina
Yes it will, When I did my son's bike, 2004 CR125. We put on a fresh cylinder also, It did not come with reed cage gaskets or power valve seals if you bike has those.
MotoSport Staff Expert
2 months 16 days ago Location: Portland, OR, USA
Yes, This kit would include all the necessary internal engine parts (including the crank bearings), gaskets and seals you would need to rebuild your engines top and bottom end. You may want to check your cases, cylinder and head for damage. These parts can be found under the OEM parts finder for your 1994 Kawasaki KX250. OEM Link: http://www.motosport.com/oem-parts/Kawasaki/1994/KX250
Luke 3 months 1 day ago Location: Tasmania, Australia
Correct piston size?
Hi, I am in the process of rebuilding my '08 YZ 250from the bottom up. I have been looking at your wiseco bottom and top end kit. I have had the bore re-sealed and the guy at my local shop said I needed a 'B' size piston (standard size according to him) and I am hoping that the piston in this kit will do the job? If not, could you suggest what I should go with. If you could possibly let me know if i am on the right track that would be appreciated. I would like to order a kit ASAP so I can back on the trails :) I look forward to hearing from you soon. Cheers Luke
MotoSport Staff Expert
3 months ago Location: Portland, OR, USA
Usually the A / B / C designation on the piston would only be for the OEM replacement cast pistons that would be best suited for the matching A / B / C cylinder. With the Wiseco Pistons they do not use these designations as the piston would be a Forged piston. Forged pistons will actually expand to fit your cylinder when the engine heats up and breaks in. So basically there is only one standard size piston from Wiseco (no "A, B or C" piston designations) but it will work with which ever cylinder you have. This kit would definitely be a great option for you if you are looking completely rebuild your engine from the bottom to the top end.
Top 1000 Contributor
3 months ago Location: North Carolina
OK, So I bought one of these kits for a 2004 CR125, and Honda had a "A" bore/cylinder and a "B", through some research and a lot of reading, Wiesco kits fit regardless of the type of bore from the OEM. My son's bike had a "A" bore, we now have 10 + hours on this kit and it is still running strong. In my opinion, regardless of the OEM type of bore / cylinder combo; I was just ensure that the overall bore diameter is correct. Also, I believe that the A or B type is probably a different casting is all. I hope this helps, safe riding!
chuckles 4 months 6 days ago
Are you sure that this will fit a yz 85 when I go on the website it does not come up as an option for a piston?
MotoSport Staff Expert
4 months 1 day ago
Yes, we do have this kit for the 2005 Yamaha YZ85 with the standard bore piston. As long as you select the correct bike selected in the "Ride You Are Shopping For" selection we will send you the appropriate kit for that bike.
Seth34 Over 6 months ago Location: Sadieville, KY 40370, USA
How can I figure out what year my cr 250r motor is? It's been swapped so I can't go by the bike.?
MotoSport Staff
Over 6 months ago Location: Portland, OR, USA
You will need to contact the local Honda service center with the engine number that is stamped in the cases located near the shifter. With this number, they should be able to contact Honda and verify the model year of your engine.
JeanPRO Over 6 months ago Location: VENEZUELA
Will this product fit me 95 YAMAHA WR 250 2 stroke?
MotoSport Staff
Over 6 months ago Location: Portland, OR, USA
Unfortunately this kit is not available for your 1995 WR250R. There are piston kits available but none of the aftermarket companies are producing a crank kit for this bike. There are rod kits available to rebuild the stock crank. Depending what condition the motor is in, a rod kit might be a good solution for the bottom end with new crank bearings, or you may need to purchase an OEM crankshaft.
gkostas Over 7 months ago
Hi i would like to ask you if there is any chance to choose a piston with larger clearance.thank you?
MotoSport Staff
Over 7 months ago Location: Portland, OR, USA
If you can give us a call, we can help with swapping in a larger bore piston into the combo in place of the standard bore piston.
Jacob Over 7 months ago Location: Alabama
Crank Seals?
Does this kit come with all the necessary crank seals? The picture shows some seals but the consumer can't depend on a generic picture. Production description doesn't mention it either. Thanks!
MotoSport Staff
Over 7 months ago Location: Portland, OR, USA
Yes, this kit does include the main crank seals.
1-10 of 18

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