Wiseco S729 Wrist Pin 23mm x 63.5mm 5115 Chromium Alloy Steel

The Wiseco S729 is a 5115 chromium alloy steel wrist pin measuring 0.9055 in. (23mm) outer diameter and 2.500 in. (63.5mm) in length with a .200" wall thickness, weighing just 140 grams. Designed for use with the W5939 lock, this wrist pin is engineered to handle the extreme demands of high-performance aftermarket engine builds.

The wrist pin — also known as a piston pin or gudgeon pin — plays a critical role in connecting the piston to the connecting rod, transferring over 11,000 pounds of force up and down the bore with every combustion cycle. Wiseco manufactures their wrist pins to precise tolerances to ensure reliable, long-lasting performance in demanding applications.

5115 Material Wrist Pin Features:

• Standard-grade chromium alloy steel construction
• Case hardened to 58–64 Rockwell C for exceptional surface durability
• Ground to a surface finish of .15 Ra or better for precise fitment
• Designed to withstand the normal wear and tear of high-performance aftermarket engine use
• OD: 0.9055 in. (23mm) | Length: 2.500 in. (63.5mm) | Wall: .200"
• Weight: 140 grams
• For use with: W5939 Lock

About Wiseco Wrist Pin Material Options:

Wiseco offers wrist pins in three distinct material grades to match your specific performance requirements:

• 5115 Steel — Chromium alloy, case hardened to 58–64 Rockwell C, ground to .15 Ra surface finish. Ideal for normal high-performance street and track use.
• 52100 Steel — High carbon, chromium-bearing aircraft-quality alloy, through hardened to 54–56 Rockwell C. Engineered for high load capacity and outstanding wear and abrasion resistance.
• 9310 Steel — High-quality, low-carbon case hardened steel, hardened to 59–63 Rockwell C, ground to a superfinish (.025 Ra or better). Recommended for turbo and nitrous applications where high contact stress meets high shock and impact loading.

Sold individually. Order the quantity required for your application. Compatible with Wiseco piston sets that specify the 23mm pin bore. Always pair with the correct Wiseco W5939 wrist pin lock.