The rivets are the small round pegsstuds that hold the chain segments together. Go kart chain pitches are either 38 inch or 12 inch.

American Sportworks 3171 Black Widow Go Kart Parts Model
Go kart chain size chart. 35 40 41 420 and 50 chain are used on american go karts and mini bikes. 35 chain gear ratio chart engine 9 10 11 12 13 14 15 16 17 18 19 54 600540491450415386360338318300284 r 55 611550500458423393367344324306289 e. Most common go kart chain sizes. Measure from the center of the first to the center of the second. The most common go kart chain sizes are 35 40 41 420 428 and 50. Hold the chain in your hand with the rollers facing up.
Go kart chain dimensions in inches. Turn the chain to find the master link pins. To determine the pitch chain size youll need to measure the distance between any consecutive rivets. An 11 or 12 tooth clutch sprocket usually indicates the use of 35 chain. 10 tooth clutch sprockets usually indicate the use of 40 41 or 420 chain. The master link pins are smaller around than the rollers and there are two side by side in the chain.
Most go kart chains and mini bike chains have the chain size stamped directly on the chain links. 35 40 41 420 428 and 50.