The formula to calculate the Gear Inch (GI) is:
\[ \text{GI} = \frac{\text{TFR}}{\text{TRC}} \times \text{D} \]
Where:
A gear inch is defined as the ratio of the teeth in the front ring divided by the rear cog times the diameter of the wheel.
Gear inches describe the mechanical advantage of different gear settings on a bike. The higher the gear inch, the greater the mechanical advantage provided from the pedals to the wheels.
Let's assume the following values:
Step 1: Divide the number of teeth in the front ring by the number in the rear cog:
\[ \frac{50}{25} = 2 \]
Step 2: Multiply by the diameter of the wheels:
\[ 2 \times 27 = 54 \text{ gear inches} \]
Therefore, the gear inch is 54.
Let's assume the following values:
Step 1: Divide the number of teeth in the front ring by the number in the rear cog:
\[ \frac{40}{20} = 2 \]
Step 2: Multiply by the diameter of the wheels:
\[ 2 \times 26 = 52 \text{ gear inches} \]
Therefore, the gear inch is 52.
