A question that only you can answer. I have two questions:
1. How much money do you think you could realistically get for it? Where do you keep it now? Is it in the way? Try shopping as if you were going to buy a comparable bike and consider how much that amount of money would change your lifestyle. That's the value of selling it.
2. If you decide to keep it, how do you plan to use it? How much do you think having it would improve your lifestyle. That's the value of keeping it.
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My greatest fear is all of my kids standing around my coffin and talking about "how sensible" dad was.