TOKYO- Suzuki Motor Corp's 85-year-old CEO Osamu Suzuki named his eldest son as the new president of Japan's fourth-biggest automaker, easing investor concerns over the firm's succession plan and boosting the company's shares by more than 5 percent.

Executive Vice President Toshihiro Suzuki took over the role from his father as president and chief operating officer effective Tuesday. Osamu Suzuki remains as CEO and chairman.

"If I don't say much and stop working, I'll get dementia, so I'll continue to work an appropriate amount," the octogenarian told reporters today.

Osamu Suzuki also said he will continue to oversee the automaker's dealings with Volkswagen AG, with which it formed a capital tie-up in 2009, along with newly appointed Vice Chairman Yasuhito Harayama, a former executive vice president and bureaucrat at the Ministry of Economy, Trade and Industry, who was hired by the elder Suzuki to oversee the issue with Volkswagen.

Suzuki Motor is now trying to dismantle those ties by buying back the 19.9 percent stake held by the German giant in an international arbitration court after the partners fell out.

Shares in Suzuki Motor rose as much as 5.5 percent after news of the management changes, before ending up 2.7 percent.

After the market closed, Suzuki laid out financial targets under a new five-year business plan, including a goal to raise revenue to a record and to boost sales to 3.4 million vehicles in the year ending March 2020.

The automaker set the dividend payout ratio for this business year at 15 percent, although CEO Suzuki said the company aims to increase this. Payout ratio for the same year was 36.6 percent for Nissan Motor Co and 29.0 percent for Toyota Motor Corp.

Suzuki is also targeting record revenue of 3.7 trillion yen ($30.24 billion) this business year, versus 3.1 trillion yen projected for the current business year.

Osamu Suzuki, born Osamu Matsuda, joined the automaker in 1958 after marrying into the family. During his nearly four decades running the company, Suzuki has turned the loom maker founded by his wife's grandfather into one of the world's biggest automakers, blazing the trail into the Indian market in the early 1980s.

Suzuki, through its local subsidiary Maruti Suzuki India Ltd, is the top-selling automaker in India and has a market capitalisation of 2.24 trillion yen ($18.3 billion), roughly equal to that of Fiat Chrysler Automobiles.