Collection: Shaft Couplers

R & D Marine flexible shaft couplings are designed to absorb vibration and reduce drivetrain stress between the transmission and propeller shaft, and every coupling in this lineup is sized for a specific combination of transmission type and power rating. Before choosing, you need to know three things: the make of your transmission (B/W, Hurth, Twin Disc, Yanmar, or Volvo are all represented here), your propeller shaft diameter (options run from 4-inch through 6-inch), and your engine's horsepower output at operating RPM. Each coupling carries a rated capacity in HP per 100 RPM, ranging from 3HP up to 28HP in this selection, so matching that figure to your actual load is critical for longevity and safe operation.

Most listings in this category are full flexible couplings, but R & D also offers a split half coupling for Volvo applications, which simplifies installation on boats where splitting the shaft is necessary for access. If your vessel runs a B/W or Hurth gearbox, you will find the widest range of power ratings here. Yanmar and Twin Disc owners have dedicated fitments as well. Because shaft coupling compatibility is highly model-specific, cross-reference your transmission's flange pattern and shaft size against the product listing before ordering, as an incorrect fit cannot be corrected with adapters.