My first bike was a Ninja 250. I bought it new and paid cash for a few reasons:
1. I had no idea what to look for in a used bike.
2. Nobody would let me test drive a used bike because I had no experience. (I know, I did it backwards and bought the bike a couple weeks before I took the MSF course.)
3. The bike was a leftover 2001 so I got it cheap.
4. There were no used 250's for sale in my area except a 1996 that some dealer wanted $2200 for.
My current bike, 99 F4, I bought used, with cash, for the same reason that I always buy my cars used. The same reasons that duessel mentioned. IT IS NOT WORTH IT. You can pay $8,000 for a new 600 and the second you sign the paperwork it becomes a used bike and loses 10%-20% of its value.
I would not take ANY loan out for a bike. I don't believe in getting loans for toys. And in the Midwest, a bike IS a toy, not your primary means of transportation.
Sure, I would like to have the latest and greatest, but it just is not worth the money you lose.