WASHINGTON — When this city rolled out its bike-sharing network last September, Aaron Adkins was not one of the early adopters. An executive assistant who wears crisply pressed suits to work, he had scarcely been on a bicycle since childhood. But these new bikes — candy apple red, rolling past traffic, seemingly everywhere — proved hard to resist.

So last month Adkins gave Capital Bikeshare a try. Laptop bag strapped to the front rack, breeze in his face, he zipped to work in less than half the usual time and became a convert in a single commute.

“Now, I’m in my office in less than 10 minutes,’’ said Adkins, 35. Surprised by the sturdiness and comfort of the bikes, he has only one complaint. “I just wish there were more.’’

It is an increasingly common refrain in Washington, where the nation’s first modern, large-scale bike-sharing program has exceeded expectations to the point of being challenged by its own success. Even with more than 1,000 bicycles and 100 stations, demand exceeds supply in many pockets of the city during rush hour, prompting calls for expansion — not just more stations, but more bicycles and docking slots per station.

“It’s really performed beyond our, I wouldn’t say wildest dreams, but beyond our normal dreams,’’ said Chris Holben, bike-sharing project manager for the District Department of Transportation. With Boston about to start a similar program in July, called Hubway, he encouraged city planners to be bold.

“Do a much bigger splash at the beginning,’’ said Holben, who helps oversee a system that opened with 50 stations, doubled in a month, and has more on the way. “The smaller the system, the more complaints you’re going to get, and you’re going to have to expand that much sooner.’’

Hubway is poised to start with 600 bikes and 61 stations, with hopes of expanding in a few years to as many as 5,000 bikes at 300 stations, reaching into Cambridge, Somerville, and Brookline.

In its first seven months, Capital Bikeshare generated 330,000 trips and seven reported crashes, none life-threatening, a much safer rate than that for trips by bike owners, Holben said. Theft of the bikes is rare, and most of the stolen ones have been recovered, the bikes too heavy to cart inside and too distinctive to conceal, even with a coat of paint.

When the first stations were put in place last year, Washington officials predicted that 6,000 people would purchase the $75 annual memberships in the first year. Instead, they hit that in six months, then doubled the number in 24 hours through a half-price promotion..

The sudden surge has frustrated some otherwise smitten Bikeshare members.