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When the 1976 350 cc and 500 cc vertical twins were recognised as a marketing disaster, Fabio Taglioni went to work developing the Pantah.
The Pantah 500 is where the current line of V twins began. Developed from the last of the GP500 racers of 1973, the Pantah and its successors have shown that, contrary to the previously accepted wisdom, a twin can race against the fours and win.
The bike was first shown at the Milan Bike Show in December 1979. The prototype was different again to Ducati’s earlier bikes: it had a trellis frame, with the suspended motor acting as a stressed member, the swingarm pivoted on the rear of the crankcase, the SOHC was driven by toothed rubber belt, the primary transmission was via Morse chain and the front disc was a Campagnolo Hydroconico.[1] The claimed performance was impressive: 500 cc, 50 hp (36.5 kW) @ 8500 rpm, 180 kg, 1450 mm of wheelbase, significantly different from the earlier bevel head V twins which were long bulky and stable, and easily surpassed the ill-conceived 1976 parallel twins.
The Pantah came onto the market in 1980 as the red and silver 500SL, with the engine using belt driven camshafts, and a plain bearing crankshaft. It had the same bore and stroke as the old 500 racer, 74 mm x 58 mm, but the head had a 60 degree included valve angle and kept the belt driven camshafts used on the final 500GP engine version. They were noticeably lacking in bottom end and mid range torque, but revved freely enough. The suspension seemed less certain than earlier Ducati models, and the 35 mm front forks lacked rigidity.
Enthusiasts found the final gearing too tall, and the intake and exhaust restrictive. If you changed those for higher flow items, and lowered the gearing, it gave a performance increase.
