What is the actual gear ratio of a mamachari(Japanese city bike) single?
Since the bike makers (Bridgestone, Miyata, Maruishi) don’t list gear ratios on their websites, I actually looked up the gear ratios of mama-chari singles (in the 10,000 to 20,000 yen range) to see what they were. I counted the number of teeth of front and rear gears at a bicycle shop. Only three of them…
Since it’s a mamachari, it often has a chain case on it, so you can’t see it.
As a result, as far as I checked the three bodies, even considering the miscounting, the gear ratio is 14~15T in the front and 32T~33TT in the rear, so the gear ratio is 2.13~2.35. If we assume that the tire size is 26 x 1-3/8, which is common for 26 inch mama-chari, the tire outer diameter is 668mm, so the distance that can be traveled by one pedal revolution is about 4.48 to 4.95m.
Calculating the distance traveled per pedal revolution
|37-590||26 x 1-3/8||650 x 35A|
Cymoto Bicycle Milton
Ion Bike Maurice Casual
Ion Bike Cadalora
I forgot to take a picture of the back. Sorry, I think it’s a 14T.