Boyesen Water Pump & Components

Boyesen SuperCooler: Engineered to Win the War on Heat

When it comes to keeping a high-revving motocross or off-road engine alive through long, demanding motos, few upgrades matter more than the water pump. Boyesen has approached this challenge with the same engineering rigor that made the brand legendary in reed induction technology — and the result is the SuperCooler Water Pump Cover and Impeller Kit, the definitive aftermarket cooling solution for dirt bikes and ATVs.

Water pump components are the heart of any liquid-cooled engine's thermal management system. Stock units are functional but rarely optimized — and that gap is exactly where Boyesen found its opportunity. Boyesen has been working on water pumps since 1999, and the switch to four-strokes has only made their effort more important. Under heavy loads, the cooling system must work to dissipate heat as it accumulates — and if the engine overheats, the best-case scenario is that performance drops; in the worst case, the engine seizes altogether.

The Science Behind the SuperCooler

What separates the Boyesen SuperCooler from a simple bolt-on cover is the depth of hydrodynamic engineering baked into every detail. Boyesen's investment-cast-aluminum water pump cover features bigger water inlets, a sculpted design, no casting seams, less restrictive bends, a more efficient impeller shape, and less cavitation.

• Patented Nautilus-Style Impeller: Boyesen's patented, hydrodynamically optimized impeller design is 25 percent more efficient at moving water than a stock unit, and it is machined from aluminum rather than the plastic used in most OEM impellers.
• Anti-Cavitation Design: Boyesen's nautilus-shaped cover and impeller increase pump capacity by eliminating the cavitation that creates air bubbles — bubbles that rob both flow volume and thermal efficiency.
• Optimized Inlet Geometry: Unlike stock units, Boyesen's water inlet has an increasing diameter and artfully curved shape — a vast improvement over most stock inlets, which decrease in diameter as they near the impeller and feature a 90-degree bend at the pump.
• Proven Temperature Reduction: The Boyesen SuperCooler can reduce engine temperatures by as much as ten degrees, as confirmed by tests at Team Kawasaki.
• Increased Flow Across All RPMs: The SuperCooler delivers increased coolant flow at all RPM ranges , not just at peak engine speed.

Bolt-On Simplicity, Race-Proven Results

By increasing the coolant passage size, creating a high-flow impeller, and smoothing all interior surfaces to reduce friction, the SuperCooler pumps more coolant at a faster rate than a stock water pump — all while sharing the same footprint as the OEM unit. That means no special gaskets, no custom fabrication, and no guesswork at installation.

Boyesen's SuperCooler project started on two-strokes in the '90s, but the concept really gained momentum in the four-stroke boom. Today, SuperCooler kits are available for a wide range of popular motocross, enduro, and off-road platforms from manufacturers including Honda, Kawasaki, Yamaha, KTM, and more — in both aluminum and magnesium cover variants for riders looking to shed additional weight.

For any rider who pushes their machine hard in hot conditions, tight trails, or extended summer motos, Boyesen's water pump and cooling components represent one of the most technically substantiated performance upgrades available. Explore the full range of Boyesen products to see how their engineering philosophy extends across the entire engine.