Engine power is the key factor in determining ratio spacing. Higher-priced engines can deliver up to 5 horsepower and rev as high as 10,000 rpm. Therefore, unless you're hauling extremely heavy loads, tackling very steep hills, or have a significantly large rider, you don’t need multiple gears with that level of horsepower.
I’ve found that the SA S3X ratios, despite being close, are exceptional because they lack pawls—essentially functioning like a compact 3-speed gearbox. The jumps between 58t, 48t, and 36t sprockets are substantial. If you’re running at 8000 rpm on 26" wheels, here’s what your speeds would look like:
1) 24 mph
2) 29 mph
3) 39 mph
This setup allows you to predominantly use 2nd and 3rd gear while still having reliable granny gear for when you need it. This gearing setup strikes a great balance between performance and practicality, giving you solid mid and top-end speeds while keeping a low gear for tough situations. For riders handling extra weight, similar to how
heavy hauling services manage demanding loads, the lower gear provides the needed torque without sacrificing efficiency in higher ranges.
