Business growth has doubled this year at Charleston Powersports, which sells cycles and recreational watercraft from its visible site off Interstate 526.

It’s only May, yet general manager Gordon Whitlock is already encouraged about next year, particularly in terms of motorbike sales.

“I can’t help but be very positive, energetic about where the industry is going to be in 2012 especially,” said Whitlock, whose outlet carries a full line of Yamaha, Suzuki and Kawasaki models. “The economy will start swinging in more of a normal fashion.”

A few miles away at Low Country Scooter, sales are up 50 percent from a year ago, owner Carl Hall said. “It’s been great,” he said. The venture touts high-end scooters such as Vespa. But it also has lines of inexpensive scooters, as low-priced as the $699 TaoTao, for people who are buying for gas savings.

The fuel benefit of a scooter is highlighted in the Savannah Highway dealership’s slogan, “Moving 100 miles per gallon.”

For somewhat different reasons, both powerful motorcycles and diminutive scooters are posting good years in the Charleston area.

Motorcycles come in a wide range of styles and sizes: cruisers, street bikes and off-roaders with 50-1,000 cc’s of engine displacement and costing $2,000 to $20,000 or more.

Brands in the market include national favorites Kawasaki, Yamaha, Suzuki, Honda, Harley-Davidson and Buell; niche lines such as BMW, KTM and Ducati and specialty custom rides such as Triumph, Victory, Big Dog and Sucker Punch Sallys.

They are earning business from loyal clientele who are seeing signs of an economic recovery and want a new bike, as well as some residual sales from people who want to cut gas costs at least compared with driving a big sport utility or truck.

At the same time, scooters are being sold that can be less than 50cc’s and cost below $1,000. But some are as large as 500cc’s and priced as high as $8,000 to $10,000. Locally sold brands include Red Streak, Hyosung, Roketa, Vespa and Piaggio.

Motorcycle ownership is growing gradually in the U.S. and in South Carolina, at least based on registration figures from the Department of Transportation’s Federal Highway Administration.

In 2009, the most recent numbers available, 105,963 motorcycles were registered in the state, up 21 percent from 87,512 in 2006. By comparison, motorcycle registrations rose 18 percent nationwide in the same period.

According to a Powersports Business survey in 2007, this is how the list of top selling models looked by market share:

• Harley-Davidson — 28 percent.

• Honda — 25 percent.

• Yamaha — 17 percent.

• Suzuki — 13 percent.

• Kawasaki — 11 percent.

• Others — 6 percent.

Whitlock said the three brands sold at Charleston Powersports have been best sellers for decades. “The bikes have been around so long now, they have a dedicated buyer,” he said.

While customers may gravitate to one brand or another, they have preferences in types and styles of bikes. The sales split at Charleston Powersports between street cycle fans and cruiser enthusiasts is 50-50, he said. Also, customers like to check out the latest changes: Manufacturers typically bring out new designs every three to four years, he said.

When it is time to buy, though, customers get serious. They have done their homework, Whitlock said. Even with the store’s high-traffic spot at I-526 and Montague Avenue, it gets few impulse buys. “Eighty percent off my customers have been on the Internet or have spoken with a sales representative,” Whitlock said.

On down at Low Country Scooter, Hall is seeing across-the-board interest from customers. That includes not only shoppers for Italian Vespas and Chinese TaoTaos but also for the popular $999 and $1,200 Eco and Glide models from Red Streak and the 250cc Hyosung crafted in Korea which carries a two-year warranty.

“It’s fun to take downtown and to the beach,” he said. “They all are selling.”