Chain - 05T (T8F) x 144 Links 102297 Mounting hole measurement on back:

Mounting hole measurement on back: 2 1/4 inches center to center (3 holes total)

5x70-6  145/70-6

but they were used on scooters a few years ago and called a carburetor controller

Rim diameter: 6"

Chain - 05T (T8F) x 144 Links 102297 Mounting hole measurement on back:Standard 8mm Drive Chain 05T T8F 144 Links T8F (8mm) chain is most commonly used on 2 stroke 43cc 50cc pocket bikes, mini choppers and electric scooters. There are two sizes of 8mm chain, 05T that has a 4. 61mm roller width and 05B that has a 3mm roller width. Chain counts include both inner and outer plates. This drive chain measurements are: 144 links about 116cm (45. 5 in) long Outer width: 10mm Chain Pitch (distance from pin to pin): 8mm Roller