Ever since the Apollo cruiser experiment in the early 1960s, Taglioni was fascinated by V-fours. In 1976, he picked up where the Apollo project left off by designing a liquid-cooled, 90-degree V-four with belt-driven, single overhead cams and two-valve desmo heads. Both 750 and 1000cc versions were built, but the design was shelved after water-cooling was deemed too complicated and cumbersome for production. A third generation V-four design, devised in 1978, consisted of essentially two air-cooled, 500cc Pantah engines siamesed so the front cylinders were separated to allow airflow to reach the rear cylinders—but adequate cooling still remained a problem. The fourth-generation V-four, dating from 1981, incorporated a dry clutch and oil cooling to help keep the rear cylinders at the proper operating temperature. With a quartet of 40mm Dell'Orto carbs, mild cams, and mufflers, this 994cc engine made an impressive 104 bhp on the engine dyno; with an open exhaust and more aggressive cams, it eventually produced 131 bhp. Taglioni saw potential for as much as 150 bhp with further tuning and the addition of fuel injection, but the V-four development budget dried up after Cagiva purchased Ducati and shifted all resources to developing the Desmoquattro engine that would eventually form the foundation for Ducati's present success.