Am I correct on figuring out that you tried the trike with three different cogs on the SA hub? The problem may not be in just choosing which cog is satisfactory but that the SRF5(w) hub may not be suitable for your trike due to the wide gap between gears delivered by the hub. Few trikes, with the exception of some low end, entry level trikes, have such small chainrings and the result is a very limited gear range. You can post the results from using one of the gear charts to make answering your question easier. Jeff Wills is right in saying that without knowing the diameter of the rear wheel, it is impossible to even guess at a gear range..


From a discussion at the SA website about this hub: "does the (w) version have 33% steps between gears, and the non-(w) version have 25% steps" The answer was "yes" so you have a hub with large changes as you shift, making it hard to find a comfortable cadence.