Vee-twin with belt drive Desmo camshafts (10,000 to 20,000 mile belt life, valves need shimming every 8000 miles). Pre ’82 500’s suffer weak gearbox and clutch, later bits can be fitted. Later bikes are reliable for 50 to 60,000 miles with few problems, although thrashed examples can ruin their cranks. Nice handler with relatively supple suspension; electrics are more reliable than early Dukes. 600TL had economy chassis but same engine as the Pantah.