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Gear-Inch (Metric Development)

Calculating Gear-Inch (Metric Development) is rather simple but if you don't want to lose time, just input the specifications and the personalized table with the Gear-Inch of your bicycle will be ready in a flash.

  Wheel Circumference          
Standard Chainrings
Personalized Chainrings
Standard Sprocket Sets
Personalized Sprocket Sets
 

The wheel circumference field has the value 2096 mm.
You can modify this value after having carefully measured the circumference of the wheel, which obviously depends on the type of wheel, the tire and inflation pressure.
Measuring the circumference by placing a tailor's tape around the tire does not give an exact result, since the measurement does not take into account the effective load on the wheel.
For a more precise measurement, refer to the following instructions:
sit on the bicycle and use the tire inflation valve as a reference point on the ground; perform one complete turn of the wheel and measure the relative distance covered.