I was in the same boat. For me it came down to this; I could pick up a dirt cheap race bike that has been ridden hard and put away wet, or I risk wadding up my DD. I figured, if I could pick up a race bike for what it would cost to 'fix' my VFR, then I'm ahead. That way, if I crash it, I can fix what I need (since it's not purdy anyways) and keep riding. If I don't crash it, and get bored of track days (yeah right), I could sell it for the amount I paid for it.
Of course I ended up spending more than I wanted... and it needs a little work... but you only live once.
If I was you, and you are stuck with 'one' bike, I'd make the 9er run double duty. What 'monthly' expenses are you talking about? The 9er is dirt cheap to ride.
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