| Cylinders | 1 |
| Bore | 95 mm (4 LD 640) - 100 mm (4 LD 705) - 102 mm (4 LD 820) |
| Stroke | 90 mm (4 LD 640 - 705) - 100 mm (4 LD 820) |
| Displacement | 638 cm3 (4 LD 640) - 707 cm3 (4 LD 705) - 817 cm3 (4 LD 820) |
| Max inclination during operation | 30°, max 30 min / 35°, max 1 min |
| Oil capacity (MAX level.) including oil filter | 2,6 lt. |
| Dry weight | 100 (4 LD 640-705) - 105 (4 LD 820) |