PISTON KIT VERTEX 77.0 D YAMAHA YZ 250 08-13, VERTEX 23391D COMPR 13,5:1
Vertex UK piston kit 23391D features a 13.5:1 compression ratio and a 77.00mm bore size. Kits include piston, rings, wrist pin, and circlips. All pistons are heat-treated with a T-5 or T-6 hardening and tempering cycle. Replacement rings are sold individually. Made in Italy. Standard pistons and components are OEM replacements. Fitted as standard in many OEM bikes. Replacement Parts: Rings 590377000001 SET, Pin 715381, Clips 72055. Cross reference numbers: Piston (Std) 17D-11631-90-00, Piston Ring Set (Std) 17D-11603-00-00, Pin, Piston 17D-11633-00-00, Circlip 93450-17129-00.
- SKU
- 23391D
- Brand
- Vertex
- Availability
- In Stock (1)
FULL DESCRIPTION
Vertex Piston Kit 77.0mm 13.5:1 Compression
This Vertex piston kit is designed as a high-quality replacement part for your motorcycle engine. Engineered for performance and durability, it meets or exceeds original equipment manufacturer (OEM) specifications.
Key Features:
- OEM Replacement: Standard pistons and components designed to match original equipment.
- Complete Kit: Includes piston, rings, wrist pin, and circlips for a full replacement.
- Heat Treated: All pistons undergo a T-5 or T-6 hardening and tempering cycle for enhanced strength.
- Premium Quality: Made in Italy with meticulous attention to detail.
- High Compression: Features a 13.5:1 compression ratio for increased power output.
Specifications:
- Bore Size: 77.00mm (Actual measured diameter: 76.98mm)
Included Components:
- Piston
- Rings
- Wrist Pin
- Circlips


