Hoverhawk Corporation

We ship WORLD-WIDE, easy-to-assemble Propulsion kits in easy-to-ship component packages and bolt-on belt reduction air drive units. We continue to expand our line of products to serve our customers' needs.

Our Belt Reduction Drive for Industrial Engines!

Our rugged belt reduction drive unit is designed for industrial engines, including the popular Predator, Honda, Kohler and Briggs/Vanguard and similar engines. These engines are commonly used on hovercraft, small airboats and industrial ventilation systems. This drive comes ready to install on your engine. Developed specifically for the harsh marine environment. It is designed for engines up to 40 horsepower which turn 3600 to 4000 RPM maximum, and is constructed primarily of aluminum and stainless steel for durability in a wet environment. The cogged belt is quiet, efficient and doesn’t slip when wet. The muffler and exhaust system on some engines may have to be re-located or modified to provide clearance for this redution drive to mount. Specify 1.4  or 1.65 or 1.75 to 1 reduction ratio. A reduction drive unit allows use of a larger diameter propeller, turning more slowly, for more propeller efficiency (more thrust per HP) and quieter operation.  Comes with Rotax 75mm bolt circle pattern for 5/16 inch prop mounting bolts.

Cost is $895 USD for up to 28 HP or $995 for up to 40 HP (has wider belt and pulleys, thicker plate)
plus shipping cost.

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Email Us Here: hoverhawk (at) gnt.net

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Our Belt Drive Unit installed on a HF Predator 22 hp V-Twin using a 3-blade Ultra Prop II Propeller

Our Reduction Drive works well with Ultra-Props too !
Belt Reduction Drive Installation Torque Specifications:

(4) 3/8 inch Backing Plate Mounting SS bolts-15 ft.lbs. or 180 in. lbs.
(6) 5/16 inch Propeller Mounting SS bolts--11 ft.lbs or 132 in. lbs.

Compact, Efficient, Reduction Drive/Propeller Air Drive Combinations For Airboats and Hovercraft
1) You supply 22 HP Harbor Freight Predator Engine-4,000 Max. RPM (cost under $600)
Add our bolt-on 1.65 to 1 belt drive--$895
Add our 42 inch 3-blade T5 fan with adjustable pitch--$295
90+ pounds thrust typical at full throttle.
2) You supply 22 HP Harbor Freight Predator Engine-4,000 Max. RPM (cost under $600)
Add our bolt-on 1.4 to 1 belt drive--$895
Add our 36 inch 3-blade T5 Fan with adjustable pitch--$295
82+ pounds thrust typical at full throttle.
3) You supply 13 HP Harbor Freight Predator Engine-3600 Max. RPM (cost under $400)
Add our bolt-on 1.4 to 1 belt drive--$895
Add our 31 inch 3-blade T4 Fan with adjustable pitch--$225
53+ pounds thrust typical at full throttle.
NOTE: If you have a Honda, Briggs & Stratton or other engine of similar HP, but limited to 3600 RPM redline, it is suggested to choose our 1.4 to 1 Reduction Ratio
Reduction Drive System. Blade pitch can be adjusted as needed to match/load your actual engine power.

An engine tachometer is needed to set your blade pitch to its optimum. Disable the engine governor, then set/adjust the prop/fan blade pitch angle of attack to act as the engine governor, to limit full throttle maximum engine RPM to or just below engine redline.



Contact Telephone Numbers:

1-251-609-0969 in United States
+1-251-609-0969 outside United States

Email:  hoverhawk (at) gnt.net





Prices, specifications, and availability are subject to change without notice. Products and materials advertised on this website are sold with the understanding that the buyer assumes all risks and hazards involved in their use or application. Buyer/User acknowledges assumption of all risks, hazards and further indemnifies seller by purchasing and/or using or reselling the products advertised and sold on this website. No express or implied warranties asserted nor fitness of merchantability claimed by Seller.