Shimano Thunnus CI4 Baitrunner Spinning Reels

Product Overview

Engineered for live-bait applications, the Shimano Thunnus CI4 combines secondary Baitrunner functionality with lightweight performance. Constructed using Shimano's lightweight carbon-infused CI4 composite material, the Thunnus reduces overall reel weight compared to traditional metal live-bait reels while maintaining structural rigidity and power under load.

The core design centers around Shimano's dual-drag system. The secondary rear Baitrunner drag allows live bait to swim freely with the bail closed, giving game fish time to take the bait without feeling tension. Once the handle is turned or the lever is flipped, the primary front drag engages to deliver up to 25 lbs of stopping power. Built with Paladin Gear Durability Enhancement, a Propulsion Line Management System, and Shielded A-RB (S A-RB) Bearings, the Thunnus CI4 is designed for smooth, long-lasting performance in demanding fishing environments.

Key Features & Built-In Shimano Technologies

• CI4 Material: Carbon-infused body construction cuts down weight significantly to reduce fatigue without sacrificing frame stiffness under strain.

• Secondary Baitrunner System: Adjustable rear drag tension lets live bait swim naturally while keeping the bail closed until you engage the main front drag.

• Paladin Gear Durability Enhancement: Uses a cold-forged aluminum drive gear and a hardened brass pinion gear to retain initial smooth cranking feel over extended use.

• Propulsion Line Management System: Specially designed spool lip geometry provides smoother line release for increased casting distance while reducing backlashes.

• One-Piece Bail: Seamless stainless-steel bail wire allows line to slide unimpeded directly to the line roller, minimizing friction and tangles.

• Shielded A-RB (S A-RB) Bearings: Anti-rust ball bearings featuring dual-sided shields to reduce sand, salt, and water intrusion.