Virtual Tour – Part 5: Sterndrives, Transoms & Accessories

Continuing from Virtual Tour – Part 4: Horsepower Highway…we will follow the assembly of Mercury Racing sterndrives, transoms and accessories.


Mike Riedi inserts the drive shaft on a Bravo One XR Sport Master gearcase.
Mike lowers the Bravo One XR upper housing on the Sport Master gearcase.

Mercury Racing offers a variety of sterndrives fit for virtually any application. Bravo One XRs are enhancements of existing designs while NXT1, NXT6 and M8 drives were designed and developed in-house for Mercury Racing sterndrive packages. The Bravo One XR is a beefed up version of MerCruiser’s Bravo One drive. It was developed to withstand the rigors of offshore racing and performance boating. Our Bravo One XR Sport Master drive targets surface piercing applications. Bravo One XR and Bravo One XR Sport Masters are popular options for boats fitted with 525 EFI, 565 and 600 SCi engine packages. Mike Riedi, who has over 30 years experience building high performance outboard gearcases, also builds Bravo Sport Masters.


Joe Backhaus building a M series transom plate.
Dave Vehrs preparing a NXT6 drive for the installation of the dry-sump oil pump.

Joe Backhaus builds Integrated Transom Systems (ITS) for Bravo One XR and Bravo Three XR drives. He also assembles M-Series transoms used with Mercury Racing  NXT1, NXT6 and M8 drives.

Next door to Joe, Dave Vehrs (when not man-handling our 18-wheel Marketing big rig in the Arizona Desert or Florida Keys) builds the drives to go with Joe’s transoms.

When I first started working here, I attended outboard and sterndrive service schools. Drive building was the sterndrive school’s main focus. A beginner quickly learns the challenge of building a drive – over and over – to get the shimming right for correct gear tolerances. It was with this experience that I gained an appreciation for what Mike and Dave do every day. I’m still a rookie; these fellas are top-shelf pros.


The accessories department provides wire harnesses for the dress line.
Outboard cowling assembly includes the application of colorful graphics.

The Accessories department is the lifeblood of Mercury Racing manufacturing. Produced here are a variety of sub-assembly components – including outboard cowlings, hydraulic trim and steering cylinders, and engine electrical wiring harnesses.  Also built here are finished products – including OptiMax Sport Jet pumps, Mercury Racing Zero Effort Controls and K-Plane trim tabs. Zero Effort Controls and K-Plane trim tabs were first developed at this Mercury Racing facility when it was the home of Kiekhaefer Aeromarine. Both were designed to withstand the rigors of offshore powerboat racing.

Zero Effort Controls

Mechanical and DTS Zero Effort Controls feature a stackable housing – combining any number of throttle and shift levers for multi-engine applications.
New Zero Effort Digital controls precisely signal the driver’s intent for an intuitive, worry free boating experience.

Mechanical Zero Effort controls set a new standard when Kiekhaefer Aeromarine first developed them in the 1980s. They continue to be used today in a variety of recreational and race applications. The development of Mercury’s SmartCraft electronic vessel and engine management system enabled Mercury Racing to update the controls with digital drive-by-wire technology similar too that found on modern automobiles, but hardened against the tough marine environment.  The latest generation Zero Effot Digital controls, first developed for the QC4v 1350 and 1100 sterndrive engines, takes the digital throttle & shift (DTS) technology to a new level of style, fit and function.

K-Plane Trim Tabs

Gary Aman working up another batch of K-Plane trim tabs.
Gary attaches the trim cylinder to the lower plate on this 280S digital K-Plane trim tab.

Another product created for racing, the venerable K-Plane trim tabs, have earned their spot on the transoms of world championship offshore race boats and high performance recreational boats alike. K-planes have evolved over time with casting updates and application variety, improved paint, better corrosion resistance and adaptation of an electronic trim sensor.  The sensor enables the operator to view tab trim positions digitally on Mercury SmartCraft equipped vessels.

I hope our virtual tour series has conveyed Mercury Racing is more than just an engine builder. We are dedicated in providing helm-to-stern propulsion solutions for recreational performance boaters and racers around the globe. Virtual Tour – Part 6 will feature the grind behind the manufacturing of Mercury Racing Propellers. You will not want to miss it!
























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