- 47,6 ccm
- 38 x 44 mm
- Grauguss rund, luftgekühlt
- 4-Gang Getriebe

Franco Morini - Components
| Type | Timespan | Name | Description |
|---|---|---|---|
| Motor | 1966 - 1974 | 4M | |
| Motor | 1969 - 1976 | 4M SS (Super Sport) |
|
| Motor | 1974 - 1979 | 4M R (Raccordato) |
|
| Motor | 1975 - 1982 | 4M Turbo |
|
| Motor | 1977 - 1983 | 4M GS |
|