Shimano Sustain FK 4000

The 2025 Sustain FK model is significantly upgraded technologically compared to the previous FJ. The main difference is the InfinityLoop line lay system, which allows the line to be laid extremely evenly and noticeably improves casting distance. The updated InfinityXross gears offer greater resistance to wear, while the InfinityDrive system reduces resistance when turning the reel, especially when retrieving heavier lures. With the addition of much more durable Duracross drag washers and extra protection against line loops, the new model delivers smoother operation, greater strength, and a longer lifespan. This is not just a cosmetic update – the Sustain FK is structurally and technically a higher-level reel than the previous FJ model.

Key features:
8+1 sealed Shimano bearings with additional protection – smooth and long-lasting operation
Metal body ensuring greater strength and durability
X-Protect system – effective protection against water and dirt intrusion
Second-generation micro gears – quieter and smoother performance
Two bearings around the pinion gear – more stable and longer-lasting gear operation
Cold-forged HAGANE gear – less wear compared to traditionally machined gears
InfinityDrive – new main shaft support structure for easier rotation and increased cranking power
Duracross drag – next-generation drag washers with significantly improved durability
Line lay and casting performance:
InfinityLoop – slow, ultra-precise spool movement for perfect line lay
Patented second-generation worm shaft oscillation system – longer casts and fewer wind knots
LONG STROKE SPOOL – extended spool design for increased casting distance
Special spool lip angle – reduces line tangling
Additional “fin” at the end of the line guide – prevents line from slipping off
One-piece line roller – reduced wear and smoother operation
Special Shimano line roller design – minimizes line twist

Rotor and ergonomics:
New-generation rotor – ~25% lighter with ~22% lower inertia
Easier rotor startup and smoother operation
Spool stabilization system – prevents wobbling even with low drag pressure
Optimized weight distribution – shifts the center of gravity closer to the rod, reducing strain on the wrist

Features:
Size - 4000
Weight - 265g
Gear ratio - 5.3:1
Bearings - 8+1
Line capacity - 0.30mm/180m
Line retrieve per turn - 87cm