Wiseco Black Edition Piston Kit TC 103 CID 9:1 +.010 Oversize - Harley Twin Cam
About Wiseco
Wiseco has forged pistons in Mentor, Ohio since 1941, supplying everything from factory race teams to big-bore street builds. Forged construction is what lets a V-twin survive higher compression and more cylinder pressure than the stock cast piston was designed for.
The Wiseco Black Edition piston kit for Twin Cam 103 CID engines offers a 9:1 compression ratio and a +.010 oversize bore. Featuring Armor X and ArmorGlide coatings, this kit is designed for enhanced durability and reduced friction. It includes premium compression and oil-control rings, engineered for compatibility with both OEM and Screamin' Eagle cylinder heads.
Why riders pick this
- 9:1 compression ratio for Twin Cam 103 engines
- +.010 oversize bore for rebuilds
- Armor X and ArmorGlide coatings for durability and friction reduction
- Premium ring package for superior oil control
- Compatible with OEM and Screamin' Eagle cylinder heads
When your Twin Cam 103 needs a bore clean-up or a slight displacement bump, the Wiseco Black Edition piston kit with a +.010 oversize is the answer. These pistons maintain a street-friendly 9:1 compression ratio while providing the robust construction and advanced coatings Wiseco is known for. It's a solid choice for maintaining reliability during a rebuild or mild performance upgrade.
Engineered for Lasting Performance
- Premium compression ring ensures an optimal seal for consistent power
- Napier second ring with taper face and underhook for improved oil control
- 3mm oil ring design with higher tension for effective oil management
- Armor X piston coating reduces wear and extends component life
- ArmorGlide skirt coating minimizes friction and improves scuff resistance
- Fully compatible with OEM and Screamin' Eagle cylinder heads
The Foundation for Your Build
This +.010 oversize piston kit is ideal for Twin Cam 103 engines that require machining to clean up cylinder bores. The combination of advanced coatings and ring technology ensures a durable and efficient engine. Whether it's a routine refresh or a foundational component for a mild performance build, these Wiseco pistons provide the reliability and quality riders expect.
Specifications
- Brand: Wiseco
- Manufacturer Part #: K2789
- Engine Displacement: Twin Cam 103 CID
- Compression Ratio: 9:1
- Oversize: +.010
- Weight: 2.4 lbs
Common questions
Will this piston kit work with stock Harley heads?
Yes, this kit is designed for compatibility with OEM Harley-Davidson and Screamin' Eagle heads for Twin Cam 103 engines.
What compression ratio does this provide?
This Wiseco Black Edition piston kit delivers a 9:1 compression ratio, suitable for a wide range of Twin Cam 103 builds.
Why would I need a +.010 oversize piston?
A +.010 oversize piston is typically used when the cylinder bore requires machining to remove wear or damage, ensuring a fresh, precise fit during an engine rebuild.
Ordering from Vtwinbikers
- Brand new, sourced through authorized US distribution — never used, never grey-market.
- Not sure it fits? Use Shop by Bike to filter by your year and model, or email us and we will confirm before you order.
- Harley-Davidson and Indian Motorcycle is all we do, so you are talking to people who ride what you ride.
| BRAND | Wiseco |
| TYPE | Black |
| SKU | K2789 |
| WEIGHT | 2.4 lb |
| 9 | 1 Compression |
