gear-dat
gear ratio
To get a 1:5 ratio, the wheel gear must be 5 times larger than the motor gear.
Common Combinations:
- 9-tooth motor sprocket $\rightarrow$ 45-tooth wheel sprocket.
- 10-tooth motor sprocket $\rightarrow$ 50-tooth wheel sprocket.
- 11-tooth motor sprocket $\rightarrow$ 55-tooth wheel sprocket.
Small Wheel Bicycle Drivetrain Specifications (12" - 16")
For small-diameter wheels, the gear ratio is designed to balance pedaling effort with the shorter distance traveled per wheel revolution. Most bikes in this category use a Single-Speed Freewheel system.
1. Typical Tooth Counts by Wheel Size
| Wheel Size | Front Chainring (Teeth) | Rear Cog (Teeth) | Gear Ratio | Purpose |
|---|---|---|---|---|
| 12-inch | 24T - 26T | 16T | 1.50 - 1.62 | Maximum torque for toddlers/beginners. |
| 14-inch | 28T | 16T | 1.75 | Balanced ratio for neighborhood riding. |
| 16-inch | 28T - 32T | 16T or 18T | 1.77 - 2.00 | Higher top speed for older children. |
2. Component Anatomy
-
The Rear Cog (The Driven Sprocket): * Standard Size: 16T is the industry default.
- Thread Type: Most use a standard 1.375" x 24 TPI (Threads Per Inch) interface, allowing you to swap cogs easily.
- The Front Chainring (The Drive Sprocket): * Larger wheels require more teeth on the front to prevent "ghost pedaling" (where the legs move too fast for the speed of the bike).
- The Chain: * Standard small bikes use a 1/2" x 1/8" chain (wider than multi-speed chains).