Drag Specialties Replacement Piston for 3.875" Bore +0.010"
Drag Specialties Replacement Piston for 3.875" Bore +0.010"
About this product
About this product
Upgrade your engine's performance and reliability with the Drag Specialties 3.875" Replacement Piston. Engineered to OEM quality standards, this cast aluminum alloy piston kit provides exceptional durability and an economical solution for rebuilding your motorcycle engine.
Description
Crafted from high-grade cast aluminum alloy, this Drag Specialties replacement piston is designed to meet or exceed OEM specifications, ensuring a precise fit and reliable operation. Certain fitments of this piston feature an advanced coating that significantly extends piston life, minimizes friction, and promotes cooler engine temperatures for sustained performance. It's the ideal choice for an OEM replacement, offering an economical yet high-performance solution for your motorcycle. Designed for straightforward installation, this piston kit is compatible with both OEM and Hastings piston rings (sold separately), providing flexibility for your build. With a standard bore size of 3.875" and an available +0.010" oversize, along with a 9.6:1 compression ratio and 4-3/8" stroke length, this piston is engineered for specific engine requirements, ensuring optimal combustion and power output. Each kit conveniently includes two pistons, along with the necessary wrist pins and clips, making it a comprehensive package for a top-end refresh or rebuild.
Features & Highlights
- OEM-Quality Cast Aluminum Construction: Manufactured from premium cast aluminum alloy, ensuring durability and a perfect fit that meets or exceeds original equipment specifications.
- Advanced Friction-Reducing Coating: Select piston fitments include a specialized coating designed to extend the piston's lifespan, significantly reduce internal friction, and facilitate cooler engine temperatures for sustained performance.
- Economical OEM Replacement Solution: Provides an ideal and cost-effective solution for replacing worn or damaged OEM pistons, delivering excellent performance without breaking the bank.
- Complete Two-Piston Kit: Each package contains two high-quality pistons, complete with wrist pins and retaining clips, offering a comprehensive solution for a twin-cylinder engine rebuild.
- Versatile Ring Compatibility: Designed to seamlessly accept both OEM and Hastings piston rings (available separately), allowing for customization based on your specific performance needs.
Technical Specifications
- Product Type: Piston
- Units: Kit (contains 2 pistons)
- Piston Material: Cast Aluminum Alloy
- Standard Bore Size: 3.875"
- Bore Oversize: +0.010"
- Stroke Length: 4-3/8"
- Compression Ratio: 9.6:1
- Vendor Part Number: 21989-07+.010
Important to Know
- Requires piston rings (OEM or Hastings), which are not included and must be ordered separately.
Shipping & Return
Shipping & Return
Free shipping to GLS parcel shop parcel box for purchases over DKK 1,000.
GLS home delivery costs DKK 59.
We do our best to ship your order as quickly as possible. All orders are generally packed within 24 hours on weekdays.
There is a 14-day return policy. Read more
Specifications
21989-07+.010
Piston
3,875"
9.6:1
Aluminum
4-3/8"
118 mm
118 mm
215 mm
3.875"
+0.010"
Kit
Reviews


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