1.99% fixed APR for the duration of a loan that has nothing to back it for collateral but a sport bike is a crazy good deal by the way. Last time I checked, most major banks will not even except a motorcycle as loan collateral (they are not worth enough and they depreciate too fast), so they will force you to take out an unsecured personal loan if they will even loan you the money at all. I hear credit unions can be a great option sometimes, but don't have much experience with them personally.

If you don't have credit card debt, student loan debt, or any other type of debt other than your current bike that is about to have the interest rate sky rocket, I say go for the new bike. Sounds like you have a good head on your shoulders and have thought it through. Most people get about as far as that new model year bike looks sick and I want it, so screw running the numbers and worrying about the future, if they let me sign I'm going to, so you are light years ahead just by caring and asking for advice.

As long as you can verify the details of the new loan are as advertized I think you will have a difficult time beating 1.99% APR anywhere with an unsecured loan, even with a perfect credit rating and verified income.