Rowing on the Bow Side of the Pin Unlike traditional oarlocks, Rollerlock has the ability to be used on either side of the pin. So when used on the bow side (AKA positive offset or reverse lock) the oar is pulls the boat rather than push it.
Many well respected rowing coaches and innovators have long proposed that this set-up may be more efficient. Here’s how Jim Dreher of the Durham Boat Company explains it…
Assuming a very quick and vertical catch, a greater catch-angle results (+5 to + 8 degrees).
This increase in catch angle is most advantageous in sweep rowing that is limited compared to sculling.
Allows for a greater portion of the blade arc to work within the most efficient (lift) phase of the stroke.
This increased efficiency combined with increasing higher mechanical advantage toward the end of the stroke arc results in greater handle acceleration toward the end of the stroke and therefore an increase in handle speed for the same effort.
What Happens During the Drive?
This steep angle of attack at the catch results in greater hydrodynamic lift due to higher gearing at the beginning of the stroke resulting albeit with initial harder effort. The drive starts as a quasi-isometric leg effort until the legs are in a more mechanically advantages position nearer to the drive’s mid-point.
The rower is forced to momentarily catch with the speed of the boat and then start to accelerate the boat. The internal mechanics of the leg angle combined with the favorable mechanical advantage of the increasing effective widening of spread accounts for a significant increase in handle velocity.
Challenges Using Rollerlock behind the Pin
A new backing technique must be mastered.
Rowers must maintain lateral pressure for the cams to aid blade positioning.
Bow-mounted riggers would need a special adaptor. Side-mounted riggers used without backstays may or may not be rigid enough. Current construction side-mounted aluminum and stern-mounted carbon wing riggers have enough torsional resistance sufficient to support behind-the-pin rowing.
Rollerlock increases ever so slightly the mechanical advantage of the rower and lever (oar) mechanism throughout the stroke. This increases efficiency (reducing effort required) as the rower’s power shifts from large muscle groups with poor mechanical advantage to smaller muscle groups with greater mechanical advantage, progressing from legs to torso to arms.
Behind-the-pin rowing will initially feel as a heavier load until the rowers get used to it. Once they do, their rowing will benefit in efficiency whether they continue to row behind the pin or in front of it as they will be forced to experience true “suspension,” or “anticipation” at the catch.
Are there other advantages to using Rollerlock?
Pitch defining catch and feathering stops contributes to better blade control and less mistakes.
The circular round design eliminates unresolved vertical force caused by unsynchronized square sleeves.
Test for Yourself! Rollerlock’s unique design can make rowing more efficient on either side of the pin. We invite you to try it for yourself and decide if it should be part of your 2016 rowing program.