I do not think Kodak is a comparable example. They used to be a supplier at an old workplace. Terrible to deal with, but had some great products, but the company was a old boys club sitting up in an ivory tower. The industry shifted completely and Kodak did nothing to adapt to it.
Is there a huge shift going on in the motorcycle world? Are cruisers of no interest to buyers? Is everyone a hipster who only wants a "cafe" racer. Are electric bikes coming down the pipe someplace to upset the market? I am not aware of it. HD has, as others pointed out, offers a range of products. Maybe as well the resurgence of Indian is taking a bite from HD. It's a cruiser without the nuances of a HD with some modern car like tech, and somewhat equal heritage to back it up, with classic styling.
The problem is, in this day and age, you don't see in advance what's gonna come and disrupt everything.
You can't invest all your eggs in one basket, and that saying is always going to stand true. Look at apple, a computer company that branched out into smartphones. Look at google, a web search company, that branched out into... everything.
Look at all these retailers, failing to adapt, closing down one by one as Amazon grabs a huge chunk of market (like Sears for crying out loud, they had all the infrastructure, but didn't believe in reinforcing their internet presence and decided to keep catering to the same crowd).
Blackberry (RIM) and Nokia, GIANTS, that crumbled because they didn't adapt enough even though they had features they thought all people wanted/needed.
Sometimes the shifts are incremental (say blockbuster from vhs to dvd) and you see it coming. Or sometimes they swoop in and blindside you (ie. streaming services destroying blockbuster and the like).
With all those regulations swooping in for emissions and electric vehicles and what not, they'll have to start adapting if they want to stay relevant as those laws tend to nudge the market towards a certain direction.
HD is quite an icon, it's great that they employ local people and what not and the heritage is pretty respectable but if they wanna remain relevant, they have to understand that no one is too big to fail (as 2008 should've taught most insitutions) and follow through on their novel ideas (like the Livewire)