Registration opens Tuesday for the Levi Leipheimer King Ridge GranFondo, the wildly popular Santa Rosa-to-the-coast-and-back ride that showcases the best scenery and roads in Sonoma County.

The ride is capped at 7,500 participants and sells out every year, having grown in four years to be one of the nation's top cycling events. This year's event will be held Sept. 29.

"It is the combination of Levi lending his name to the ride and what Sonoma County has to offer," said Marc Hagenlocher of Santa Rosa, a former professional racer. "This ride in Mississippi wouldn't be as popular. It is where we are and what Sonoma County has to offer."

The fondo (an Italian word used to describe some cycling events) has three routes. Its 7,500 riders will stream out together from the Finley Center in one colorful, massive start that will have cyclists wheel-to-wheel for several miles.

The shortest route is the piccolo, just 32 miles to Occidental and back. The 65-mile medio route continues to the coast by way of Duncans Mills and returns over Coleman Valley Road.

The 103-mile granfondo route includes the ride's name-sake King Ridge in Cazadero and is the most popular, with 4,000 slots that will sell out within a few days.

On-line registration for the three routes opens at 9 a.m. Tuesday at Fees are $75, $125 and $145, depending on the route.

Last year's crush of registrants overwhelmed the organizer's computer servers, causing a two-day delay while registration was moved to new servers and forms were rewritten for easier loading.

"The way the registration form talks to our database has changed, and the servers are far more able to handle the volume," said Greg Fisher of Bike Monkey, the event organizer.

The ride, which is the brainchild of Santa Rosa pro racer Leipheimer, started in 2009 with 3,500 riders. It was meant to help the City of Santa Rosa raise money to host the Amgen Tour of California, the top professional bike race in the United States.

But the fondo quickly became a premiere event in itself, drawing participants from throughout the United States and overseas, filling hotel rooms and restaurants and benefitting the Sonoma County economy.

"In terms of the return to the economy, it has surpassed the tour itself," said Raissa de la Rosa, the city's economic development specialist. "The people who ride in the GranFondo travel with family and friends, 60 percent, and stay multiple days. They come in for mini-vacations."

The GranFondo also raises more each year than the $60,000 owed to Santa Rosa tour organizers.

In 2011, the fondo brought in $266,000. Organizers gave $79,800 to the Forget Me Not Farm charity, $22,000 to schools and fire departments in west Sonoma County, $11,300 to Lance Armstrong's Livestrong charity and $93,500 to other cycling programs that are overseen by VeloStreet, Leipheimer's non-profit agency, which owns the fondo.

]You can reach Staff Writer Bob Norberg at 521-5206 or bob.norberg@