A moped's engine may have a maximum displacement of: Before you start the test, please answer the question below regarding your insurance status. Without insurance you will not be able to drive in Ohio Do you currently have car insurance? Yes I have insurance. Great, you're all set! Click here if you still want to compare rates. No, I need insurance. Click here to compare rates from our insurance partner. Question A moped's engine may have a maximum displacement of: Answers 10 cubic centimeters. 20 cubic centimeters. 50 cubic centimeters. Explanation As defined by South Dakota law, a moped may have an engine displacement of no more than 50 cubic centimeters. This questions appears in the following tests: South Dakota Motorcycle Practice Test 17 South Dakota Motorcycle Practice Test 16