Arc Length and Gearing
Many coaches contact us for advice on gearing and in particular choice of oar length.  General advice is easy to give knowing that in reality a lot of crews now use equipment that is adjustable within a small specification range.

From Kleshnev (2007) we know the following:

  • 60deg catch angle - twice as heavy
  • 70deg catch angle - three times heavier
  • 80deg catch angle - six times as heavier
Gearng Ratio vs Oar Angle
 
If we consider the information shown in the graph, we can see that loading is significantly increased dpending where the catch angle is actually taken.
 
The first consideration therefore be "are my crews rowing the ideal catch angle" and if so then we can fine tune the oar length to suit the ability and strength of the crew.
 
Our three step process is as follows:
  1. Select oars in a length range to suit the ability of the crew.
  2. Encourage length of an effective stroke as a priority.
  3. Fine tune rigging and oars for final loading effect. 
Reference:
Kleshnev, V 2007, ‘Facts. Did you know that…’ Rowing Biomechanics Newsletter, vol.7,no.72, retrieved 16 August 2010, <http://www.biorow.com/RBN_en_2007_files/2007RowBiomNews03.pdf>