Ducati twins · 1975–1983
Ducati 350 and 500 GTL and Sport Desmo: history and buying advice
Ducati’s parallel twins: good-looking, but notorious.
History
In the mid-seventies Ducati wanted a cheaper twin to compete with the Japanese parallel twins. Bruno Tumidei reworked an old Taglioni prototype into an engine with a single chain-driven overhead camshaft, a 180-degree crankshaft and plain bearings. Giorgetto Giugiaro drew the GTL. Leopoldo Tartarini drew the sportier Sport Desmo, with a Taglioni desmo head. The GTV was a Sport Desmo with the GTL engine.
The bikes sold badly and were unreliable, and earned the nickname ‘paralysed twins’. The oil supply to the camshaft and the build quality were particularly weak. Sport Desmos were largely built at Italjet. Spain’s MotoTrans kept building the 500 until 1983.
Key data
| Engine | parallel twin, 180° crankshaft, chain-driven camshaft |
|---|---|
| Bore × stroke | 500: 78 × 52 mm; 350: 71.8 × 43.2 mm |
| Power | 500 GTL: 35 hp; 500 Sport Desmo: c. 50 hp; 350 Sport Desmo: 42 hp |
| Gears | five |
| Top speed | 500 GTL: c. 170 km/h |
| Weight | 500 GTL: 170 kg dry |
What to check when buying
- Check the oil level often and ask about the oil lines: the oil supply to the camshaft was a weak point.
- The oil reservoir in the engine needs frequent oil changes. Ask about the maintenance.
- It vibrates a lot at low and medium revs. Check brackets, mudguards and exhaust mounts for cracks.
- Establish the version: GTL, Sport Desmo or GTV, and Italian or Spanish built.
- Parts are scarce. Prefer a complete example.
SourcesWikipedia: Ducati parallel twins (English)Rider Magazine: Ducati Sport Desmo 500 (English)