The weight of a single-cylinder 150 cc bike engine can vary depending on various factors such as the design, materials used, and additional components. However, as a general estimate, a single-cylinder 150 cc bike engine typically weighs around 20 to 30 kilograms (44 to 66 pounds).
It's important to note that this weight range is an approximation, and actual weights can differ between different motorcycle models and manufacturers. Additionally, the weight may also be influenced by factors such as the presence of electric start systems, cooling systems, and other accessories or components integrated into the engine design.
For a more accurate weight specification, it's advisable to refer to the specifications provided by the specific motorcycle manufacturer or consult the technical documentation of the engine in question.