Three-wheeler manufacturer Piaggio Vehicles is planning to introduce petrol- and gas-based versions of its vehicles.Ravi Chopra, chairman and managing director, Piaggio India, said today that the development of engines that will run on petrol and gas is currently on, and an announcement of the company's entry into the petrol three-wheeler segment can be expected "soon."Chopra said the company enjoys 55% share in the diesel three-wheeler segment and 36% in diesel passenger vehicles. "The market is expanding, and we feel the need to be present in all the segments of the three-wheeler category," Chopra said indicating a market potential of 100,000 petrol and gas three-wheelers every year. Piaggio also launched the Extra and Extra LD (Long Deck) versions of its diesel three-wheeler in the Pune market.