Generally speaking, the ST series bikes have a bench-type seat, small wide tires, and folding handlebars. They have an air-cooled 4-stroke engine with a 3-speed semi-automatic transmission with an automatic centrifugal clutch, or a 4-speed manual transmission.
Due to their small wheel size and limited speed, ST-series motorcycles are not always considered street legal and have been sold in some markets only for off-road recreation. Their registration status has varied by location and time period over their nearly 40-year history.