OK- bike/trike people call the gear up front a "chainring" and the gear on the rear hub a "cog". It's a little confusing when you say you have a 22-tooth cog on rear hub then you say you have a 14-tooth cog on it. Which is it?

Another thing that makes a difference is the rear wheel size- is it 20-inch? 26-inch? Is it a homebuilt trike? A commercial trike? What brand?

Here's a good primer for figuring out your trike's gears and a calculator to figure out the different gear ratios:
https://www.sheldonbrown.com/gears.html
https://www.sheldonbrown.com/gear-calc.html
(Yes, the gear calculator will do the ratios for your SRF-5 hub.)

It's not really all that different from figuring out the gear ratios for a car on different race tracks.

My career(s) started in the bicycle business as a mechanic and parts finder. I also built recumbent trikes nearly 40 years ago. I had my fun but now I have a "real" job. This is where I started:



As to rotaries... a while back I ran across a JDM Mazda Cosmo with a 20R engine at the local Starbucks. I had to wipe the drool off my chin.