How much horsepower is 159cc?

159cc is not a measure of horsepower. It is a measure of engine displacement, which is the total volume of the combustion chambers in an engine. Horsepower is a measure of power, which is the rate at which work is done. The relationship between engine displacement and horsepower is complex and depends on many factors, such as the engine design, air/fuel mixture, and engine speed. In general, however, larger engines tend to produce more horsepower than smaller engines.