Every afternoon, as the sun dips toward the Indian Ocean and the ruins of blasted homes cast long shadows across scattered rubble, the roar and whine of motorcycles slice the languid air.

Street racing has returned to the tsunami zone.

Young men hunch low over dark metal. Hundreds of people again converge along the boulevard to watch, clustered on broken sidewalks and weedy lots, perched on foundations and tumbledown porches stripped of their homes by the December tsunami. Knots of girls, some in traditional Muslim head scarves, eye their hot-dogging heroes from an honorable distance.

The massive wall of water that crashed into Aceh province on Dec. 26 had stilled the engines. The disaster killed nearly a quarter of the population of Meulaboh, the largest town on the west coast of Indonesia's Sumatra island. The wave razed entire neighborhoods and buried the long straightaway of Iskandar Muda boulevard in mud, bloated corpses and the jetsam of urban lives.

But gradually, the raceway was cleared. Laborers excavated the traditional, if illegal, track with its narrow median strip, zebra-striped curbs and finish line at the palm-fringed beach. In doing so, they also unearthed a hankering for old habits and, locals admit without shame, a little fun.

In the last two months, the riders have reappeared. They scream along the half-mile course running from the edge of downtown straight into the setting sun, flip their bikes around in a screech of burning rubber and return.

Inevitably, bikes collide or a tire clips the curb. Metal crunches on blacktop.

"He fell! He fell!" yelled spectators watching the races on a recent afternoon.

Necks craned. Several men sprinted toward the accident.

"It's Waldi!" shouted one, referring to the reigning champion, a solidly built, shaggy-haired teenager in a green shirt who had lost control trying to turn his bike around at high speed. Somehow, defiantly, Waldi managed to haul himself to his feet, rubbing his forearms, and wheeled his motorcycle out of the way.

"The injuries usually aren't serious," volunteered Adrian, 28, an enthusiast with a thin mustache, watching from the shade of a crumbling brick wall. "The only serious injuries are when a goat cuts through and gets hit."

Once, long before the tsunami, a stocky, full-faced man named Ornel had been the local champ. He was a jago, a real hotshot, ogled by the girls until he got married two years ago and retired. Now, Ornel, 29, watches keenly from the seat of his Honda.

"There's racing. That's all there is," he said.

There are no bars in Meulaboh, no discotheques or movie theaters. The lone karaoke club has remained shut since the tsunami. Even the once-popular night carnivals, with their carousels, bazaars and magic shows, have yet to return.

Ornel recalled the days of his youth when his city had a nightlife. Headline singers from as far away as the Indonesian capital of Jakarta used to tour Aceh.

But the late 1990s saw an escalation in the long-running conflict between Acehnese separatists and Indonesian security forces. Curfews and fear kept entertainers away. More recently, Aceh imposed Islamic law, or sharia, adopting stiff measures against drinking, gambling and mingling of the sexes. Then came the tsunami.

"There's less than before, much less, almost nothing," Ornel said.

Meulaboh's arduous rebirth is only now taking shape. Hundreds of new homes are being built to replace the refugees' tents and clapboard shanties. Construction of a new city pier began in late June. The flimsy stalls of the traditional market, where people hawk fish, vegetables and tropical fruits, have been rebuilt, but at a more prudent distance from the sea.

The coffee shops of Meulaboh opened within days of the tsunami. Adult men again measure the time between calls to prayer with cups of Aceh's famously robust brew.

But for family fun, nothing beats a good race.

Motorcycles are the universal form of transportation, and men pile their clans on board, bound for the boulevard. Parked along the roadside, fathers sit high on their bikes, children on their laps, wives squeezed behind on the few remaining inches of seat.

"Nearly everyone likes to watch the racing," said Ornel's friend Jefri, 25, another cocky retired rider with combed-back hair, sideburns and a shadow of a mustache. "It relieves stress."

The races usually continue until the hour for twilight prayers. The engines fade just as the call to worship swells from countless mosques. But sometimes, the spectacle stops sooner, abruptly.

On a recent afternoon, about a half-hour shy of prayer time, the crowds suddenly began to scatter like a flock of birds taking wing. The reason became apparent only after the spectators revved their engines and begin to peel away from the curb.

"Police!" someone cried.

Moments later, a pickup truck appeared with a pair of traffic cops in the front seat. They drove slowly along the boulevard, clearing the roadsides and herding the onlookers into the sunset.

Residents sit amid ruins of a home destroyed by the tsunami to watch races in Meulaboh, the largest town on the west coast of Sumatra.