MXA PRODUCT TEST:
BOYESEN SUPER COOLER WATER PUMP AND IMPELLER
WHAT IS IT? The Boyesen Supercooler is an aftermarket water pump (cover and impeller) that improves water flow, engine cooling and efficiency.
WHAT’S IT COST? $219.95.
CONTACT? (800) 441-1177 or www.boyesen.com.
WHAT’S IT DO? Boiled down to its essence (pun intended), the Boyesen Supercooler flows more water than stock water pumps. Boyesen has been working on water pumps since 1999 (during the two-stroke era), and the switch to four-strokes has only made Boyesen’s effort more important. Four-strokes run hot—very hot. The Boyesen Supercooler can reduce engine temperatures by as much as ten degrees, as confirmed by tests at Team Kawasaki. How does the Supercooler achieve this? Hydrodynamics. Boyesen’s investment-cast aluminum water pump cover has bigger water inlets, a sculpted design, no casting seams, less restrictive corners, a more efficient impeller and less cavitation.
Most MXA test riders feel that both the Suzuki RM-Z and Kawasaki KX-F offer marginal cooling efficiency.
WHAT STANDS OUT? Here’s a list of things that stand out with the Boyesen Supercooler water pump and impeller.
(1) Casting. By casting a totally new water pump cover, Boyesen was able to maximize the flow through the unit. Boyesen’s design takes advantage of everything from Bernoulli’s Effect to biological studies.
(2) Internal shape. Stock water pumps aren’t very hydrodynamic. Their internal shape and impeller create excessive amounts of air bubbles in the water. Air bubbles lessen not only water flow, but the amount of water per cubic gallon. Boyesen’s Nautilus-shaped cover and impeller increase pump capacity.
(3) Inlet size. Unlike the stocker, Boyesen’s water inlet has an increasing diameter and artfully curved shape. This is a vast improvement over most stock inlets, which decrease in diameter as they near the impeller and have a 90-degree bend at the pump (a very serious hydrodynamic no-no).
(4) Impeller. Boyesen’s patented impeller design is 25 percent more efficient at moving water than the inefficient stocker.
(5) Colors. The Supercooler is available with silver, magnesium and black coatings.
WHAT’S THE SQUAWK? No major complaints.
If you race four-lap races, this is a three-star product (fighting heat works best when you ride long enough to generate heat). For the serious local racer, this is a four-star product. If you own a Suzuki, Kawasaki, or race long motos, this is a five-star product.
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