I must admit that I have some parts in my basement that fits bikes that were sold years ago. Nothing like what you have though. Mostly just leftover oil filters, spark plugs, a stock seat or two, a few engine parts, etc. But what I do have too much of is in the way of navigation and communication devices, and riding gear. Lots and lots of riding gear and old helmets that are just taking up space. The other thing that I did have, and finally gave away a couple of years ago, was motorcycle posters. I probably had upwards of 500 posters at one time. I collected them every year for many years at the Mid-Ohio AMA supervise weekend and the Vintage Motorcycle Days. Brought them home and stored them in cardboard tubes. Many were signed by the riders. They didn’t take up a lot of room that way. But I gave many away to some young kids looking for garage art. I did keep some of my favorites and still have them. I’ve also collected motorcycle toys for many years and have a complete cabinet of them.
I building a legacy for my kids to remember (and curse) me by after I’m gone. 😁