I've been trying to figure out just what the hell's going on with Portland's much-discussed bike share system. As we reported this week, no one on the front lines of finding $5.5 million in sponsorships for a 750-bike system is saying anything about that work, but it seems pretty clear we're looking at another delay.

Since Portland Bureau of Transportation Director Leah Treat refused to discuss this with me, and Alta Bicycle Share Director Mia Birk says she can't share anything, I've been turning outward to try to get a sense of why we're having trouble corralling cash.

In this week's story, I included the comments of Susan Shaheen, a researcher at University of California, Berkeley, who's studied bike share systems throughout the world. She floated the possibility that title sponsors—the companies that kick in big-time money to name bike share systems, pick the color scheme and slap their names all over the tank-like bikes (think Citibank to New York's Citi Bike system)—aren't as excited about bike share as they used to be.

"Maybe part of this issue is: When these first title sponsors sign on, it's exciting and it's new," Shaheen told me. "For the fourth and fifth installment, it's not as exciting. Maybe the first couple cracks at this was considered a better bang for your buck."

I heard a similar suggestion from Parry Burnap, who got Denver's B-Cycle program up and running in 2008—partly by finding willing sponsors, partly by tapping a bunch of money left over from the 2008 Democratic National Convention.

"For Denver, things lined up in a way," Burnap said. "Bikes were pretty new. There was no feeling that, yeah, we've been there, done that."

Fair enough. I figured maybe Portland's having trouble because we sort of missed the boat on bike share. Even huge metropolises with systems up and running—Chicago, DC, San Francisco—are operating on public money. They've not been able to attract a big sponsor like Citibank or a Barclays (which sponsored London's system).

Then I talked to Holly Houser, executive director of Puget Sound Bike Share, which is having its own troubles scrounging up corporate money.

She'd read our story, and Shaheen's theory.

"I really strongly disagree," Houser said. "I think it's quite the opposite."

She said, if anything, Citibank's sponsorship had made big companies more excited about bike share. And she sent along a couple articles (here and here, both from back in July) suggesting Citi has seen big-time payoffs in perception for its $41 million investment.

"Citibank kind of took the first step and I think rally took center stage," Houser said. "We have seen a lot more interest come up and, especially on the West Coast, a better understanding of bike share."

Also: Slapping your logo on a bike share station is pretty much the only way to get advertising in the right-of-way up in Seattle, she said. It would be a huge potential boon.

Fine. So why is Seattle struggling?

"I think part of it is the kind of money" available in Seattle, Houser told me. Many of the big sponsors for bike share systems, both in the US and internationally, have been banks or health care companies—organizations that might have dubious reputations, and aren't very successful with media campaigns geared toward millennials. Contrast that with Seattle's big fish. Amazon, Microsoft, and Starbucks probably don't need the help.

It's easy to see the same being true here. Nike? Intel? They don't have to shell out $5.5 million to win Portland's allegiances with some bulky bikes. Maybe Kaiser Permanente—who Alta's been courting—will ultimately give in to our advances. Maybe not.

It's not super heartening that wealthy Seattle, which is hoping for 500 bikes at 50 docking stations, only needs to corral about $1.75 million to get things off the ground and still can't find it. We need far more than that.

Of course, we could always pay for the thing ourselves and wait for the money to trickle in, something PBOT officials have mulled in internal documents [pdf]. Or, we could take what money we can get and roll out a smaller system, something Houser's also contemplated.

Not that she thinks it will come to that.

"I'm really confident that we're going to find the money that we need. I don't doubt that it's going to happen."