Wiseco V-Twin Piston Kit - 1340 EVO BIG Twin 8.5:1 Comp — Harley-Davidson Electra Glide Classic, Softail Custom, Softail Heritage Classic (1984-1999)

Wiseco forged piston kit for 1340cc EVO Big Twin engines at 8.5:1 compression ratio. High-silicon aluminum construction delivers strength and heat transfer for long-term reliability in stock and mildly modified applications.

Features

• Forged high-silicon aluminum with low expansion rate
• Diamond-turned finish eliminates size variation
• Compatible with cast iron, chrome, nikasil, and boron composite cylinder bores
• Reduced weight compared to OEM cast pistons
• State-of-the-art CNC manufacturing

Specifications

• Brand: Wiseco
• Manufacturer Part #: K1640
• Engine: 1340cc EVO Big Twin
• Compression Ratio: 8.5:1
• Weight: 2.98 lbs

Fitment

Fits V-twin motorcycles with 1340cc EVO Big Twin engines, including Harley-Davidson Touring and Softail models from that generation.

Frequently Asked Questions

What compression ratio are these pistons?

8.5:1 compression ratio, suitable for pump gasoline and stock EVO applications.

Can I use these in my resleeved cylinders?

Yes. Wiseco pistons work in cast iron, chrome, nikasil, and boron composite cylinders, and can be used in resleeved cylinders as well.

Do these pistons require new rings and pins?

Confirm ring and pin specifications with your machine shop. Complete kits typically include rings and pins — check your order contents.

Will these fit my Twin Cam or Milwaukee-Eight engine?

No — this kit is for 1340cc EVO Big Twin engines only. Twin Cam and M8 engines require different piston kits.