It probably comes down to cost of ownership vs enjoyment. Cost can be financial., but you could also figure the aggravation and inconvenience of ownership as part of the cost. Will you have a decent place to keep the bike where you're moving? Is your insurance for ownership going to be higher in Sacramento than where you live now? Do you want to keep up with the maintenance of a bike that you don't ride very much, or is that going to end up being a pain in your ass? How much did you actually ride a bike before your big trip? Was it about the same amount that you're riding it now? I know you said you've been riding since you were 16, but have you owned a bike that entire time? If you have, did you ride them about as much as you're riding the Super Tenere now? If you've always owned a bike, and your riding habits are about the same as they always were, what makes you want to get rid of the S10?
Do you really enjoy riding for the sake of riding, or does your bike represent more of a feeling of nostalgia for that big trip you took, and that's what makes it tough to part with? Even if the pleasure you get from owning it is wrapped up in nostalgia from that big trip, that's not a bad reason to hang onto something; lots of people hang onto things that don't have a practical purpose, simply because knowing they're there makes them feel good. Or is nostalgia too high a price to pay for you for a bike that you don't ride a lot, that takes up storage space in your garage, or is at risk for theft parked on the street?
I've owned a bike since I was 18. I'm in my 50's now, and the idea of parting with a bike for a reason other than financial or practical reasons like I outlined about wouldn't occur to me. For me, the pleasure I get from owning one far outweighs the costs of owning one. The only reason I'd get rid of the Yamaha would be to get a different bike, but not to get rid of a bike entirely. Even if I stopped riding it as much as I do now, I'd still get pleasure from riding it on a more limited basis. I'd never try either talking someone into or out of owning a bike; only you can decide that. But you can ask yourself some of those questions, and decide if your own pleasure of owning the bike outweighs the costs.
