The Solo 2625 is a series of German aircraft engines, designed and produced by Solo Vertriebs- und Entwicklungs GmbH of Fellbach for use in ultralight aircraft, self-launching sailplanes and homebuilt aircraft.
The engine series are all twin-cylinder two-stroke, in-line, displacement, liquid-cooled, gasoline engine designs, with poly V belt reduction drives. They employ dual electronic ignition ignitions systems and produce , depending on the model, with a compression ratio of 9.5:1.