I would think that a good spark would indicate a good CDI. ALL the Kymco manuals show digital multi testers so if your Vichy V97 is a digital it should be just fine. Most digitals including the really cheap ones like mine have very good sensitivity with very high ohms per volt on voltage tests and good accuracy on all other scales. BE ADVISED, however, the Kymco specifications are not always correct. Additionally, even good digitals are prone to occasionally give "goofy" readings. These are mostly due to poor contact in the rotary switch for selecting the ranges. A quick twist left and right should tell the story. So there is no confusion: disconnect the meter from circuit under test, twist the rotary switch left and right, reconnect the probes to the circuit under test and see if you get a different reading. Use a fresh dry cell to see if you get a consistent 1.5 volts or higher. test that unloaded cell several times to see if you get the same reading. Do the same with a resistor with a known value. This should generally PROVE the meter. If in doubt, take two electrons and call me in the morning!
Karl