NEW DELHI – Yamaha Motor Co. is joining other Japanese competitors to add motorcycle capacity in Asia’s second-fastest growing economy, betting on demand from Indians seeking personal transportation.

Yamaha’s unit will invest $151 million to triple capacity by March 2013, it said last week. Suzuki Motor Corp. will spend $19 million to produce more two-wheelers, added Atul Gupta, vice president for sales and marketing.

Honda, which reiterated a plan to almost double two-wheeler capacity in India by 2013, and other Japanese motorcycle makers have unveiled new models at the New Delhi auto show, counting on economic growth to generate demand in the South Asian nation. Prime Minister Manmohan Singh said last month India will return to 8.5 percent to 9 percent trend growth after the global economy stabilizes.

“The last two years were exceptional, and we have seen a normalizing in the market,” said Roy Kurian, national business head of India Yamaha Motor Pvt. ”We have no reason to believe that our sales will tumble.”

The pace of expansion in Asia’s third-biggest economy may slow to 7.5 percent in the fiscal year ending March 31, Singh said, compared with 8.5 percent in the previous 12-month period.

“Our two-wheeler segment is in sync with the Indian economy,” said Naresh Kumar Rattan, vice president sales at Honda’s motorcycle unit. “So long as it continues to expand at its current pace, we don’t foresee any reduction in demand.”

Yamaha will raise motorcycle and scooter capacity to 1 million units from 330,000, Kurian said. The company from Iwata City, Japan, introduced its first scooter in India on Thursday.

Suzuki Motorcycle India, the wholly owned subsidiary of the Hamamatsu, Japan-based company, will increase capacity to 540,000 units by 2013 from 360,000 now, Gupta said.

Honda Motorcycle & Scooter India introduced six new models of motorcycles and a scooter Thursday, including the 110cc Dream Yuga. The unit of the Tokyo automaker is targeting 30 percent market share by 2020 from 14 percent now, Rattan said.