While not keeping bikers up at night the curious case over who left who, the motorcycle manufacturer or advertising agency, has many wondering.

To set the stage it would be best to understand the players. An established and widely considered traditional advertising Minneapolis-based advertising company, Carmichael Lynch has enjoyed the legendary brand of Harley Davidson as a client for over thirty-years.

With all the recent headlines however, a long-standing corporate relationship has seemingly turned into an episode of the award-winning television show 'Mad Men'.

To put that corporate relationship in perspective, Carmichael Lynch have effectively been the agency promoting the famous brand since thirteen Harley-Davidson senior executives signed a letter of intent to purchase Harley-Davidson Motor Company from AMF.

But in a statement Monday Carmichael Lynch said that it could take the Harley brand no further.

"It's in our best interest to part ways," said Doug Spong, president of Carmichael Lynch.

With such a long relationship between the two companies, it wasn’t shock or disappointment from Harley-Davidson over the Ad agency’s decision, but more of a corporate shrug. Adding some spice to the story, an official at Harley-Davidson was rumored to have stated that Carmichael Lynch lacks the digital, Social and Search capabilities that are needed for a modern advertising campaign for advertising online.

And rumors can be traced back as far as 2008 that Harley-Davidson was looking for a new advertising agency, supposedly spurred on by the concerns over an aging demographic making up the motorcycle manufacturer’s customer base.

The issue of who made the decision to end the relationship is further clouded by the timing of the announcement. While Carmichael Lynch promised there would be no staff cuts from the change with business to fill the motorcycle void of $10 million to $12 million in media spending coming from new clients. Rather than acknowledge the new business now, the advertising agency promised the clients would be announced one by one in coming months.

"We want some distance between the Harley-Davidson news and our news of competing for and winning new business," Spong said.

Regardless of why it came about, Carmichael Lynch were with Harley-Davidson when some of the most memorable advertisements came about such as the baby and the simple question, 'When did it start for you'.

In other work the agency tried to capture the independence of bikers, as seen in the ad featuring a woman in her riding leathers applying mascara and using chrome on the engine as a mirror while another was of a lone rider on an open road with the line of ‘Somewhere on an airplane a man is trying to rip open a small bag of peanuts.’

The advertising agency can also lay claim to the famous 'Black Sheep' commercial that managed to bring symbolism, motorcycles and Guns n Roses together.

Recently, Carmichael Lynch was reportedly responsible for bringing on supermodel Marisa Miller in the effort to attract more women riders and the creations of the ‘Harlistas’ to appeal to the Hispanic community.

Regardless, the Milwaukee motorcycle manufacturer were at the corner of C’est la vie and ‘whatever’ when the announcement was made by Carmichael Lynch, replying with their own statement that the company would not seek a new agency of record but would instead work with "a more diverse group" of ad agencies.

And Harley-Davidson has apparently been spreading the responsibility of advertising its legendary brand around for some time; McCann, VSA Partners, Davie Brown and GS Design are all currently used by the company.

"Our strategies have been moving away from a singular consumer target and a one-size-fits-all agency solution," said Mark-Hans Richer, Harley's chief marketing officer. "Rather than accept this new reality, [Carmichael Lynch] chose a different path, and we respect that."