For 26 years, the Downtown Boise race has been a part of the city's summer, a popular annual cycling event that attracted as many as 30,000 fans.
But race organizers have just weeks to secure funding for the 27th version in July.
"We don't want to do an injustice to the event. Going backwards is not something we want to do," race director Mike Cooley said.
Exergy, the race's title sponsor each of the last two years, will not return. The company announced Friday that it was canceling the Exergy Tour, a women's professional stage race in Idaho that debuted last year.
The tour attracted a world-class field of past, future and current world champions and Olympians to Idaho with stage races in Boise, Nampa, Kuna and Idaho City.
The first tour was a hit, attracting big crowds and sparing few expenses with the online tour tracker and elaborate finish-line set-ups. But the estimated $2 million price tag made it too expensive for Exergy to maintain; it announced the race's cancellation on Friday.
"It's definitely a bummer," said Boise cyclist Kristin Armstrong, a two-time Olympic gold medalist.
Armstrong was the star attraction in last year's tour, but she crashed in the prologue and broke her collarbone. She rebound to win gold in the London Olympics last summer.
Exergy sponsored Armstrong's team and she currently works as an adviser for the company's women's cycling team, one of its few remaining commitments to cycling.
"To bring a world-class women's cycling event back to the state of Idaho was really exciting for me and so many others," Armstrong said. "Unfortunately, I don't think there are many events that are sustainable for too long that are being sponsored by one big cash sponsor."
Exergy Development Group LLC is a company that specializes in renewable energy products, like wind turbines.
Lingering uncertainty over rules governing wind energy in Idaho created a "hard time" for the 12-year-old company, with investors worried about participating in projects, Exergy Vice President Elizabeth Woolstenhulme said last summer.
Exergy also contributed $40,000 of the $80,000 cost to last year's Twilight Criterium, Cooley said.
Most of the other 17 sponsors, including the Idaho Statesman, from last year's race are back for 2013, said Karen Sander, executive director of the Downtown Boise Association, which produces the criterium.
Cooley said the race needs at least $15,000 more to stage this year's event on July 13, though it could mean trimming some of the races.
"(The criterium) is such a great community tradition ... Such an important event for Downtown and the cycling community in general," Sander said.
Cooley and Sander said they need to make a decision soon, perhaps by the first of April.
"The riders and managers and teams are making plans and we don't want to screw anybody up," Cooley said.
Cooley hoped the criterium could make 30 years, but he said he doesn't want to have to reach out to the public every year.
"We're not going to go through that. We have to have a title sponsor," Cooley said. "I'm not a professional fundraiser.
"If we have one last big party, that would be fine, too."
Statesman reporters Patrick Orr and Cynthia Sewell contributed to this report.