Ahoy hoy!

[alanmcorcoran]

You can clean or replace it. I believe many folks on here clean them in a bucket of kerosene (do a search.) If it's just got surface rust on it it should be okay. I think the mileage is probably a better indicator of wear.

As I said before, I think you'll be fine if you ride it prior to the MSF, but to each his own. (You can often download the MSF instructions. Typically they have you in first gear after about an hour or so on the course.) I'd wait until you ride it. I'd say based on my expereince and what I've observed on this board, you are far likelier to trade the GZ for a bigger bike than to find that the 16T makes it all worth while. The boost of the 16T is in the low end (from what I hear) and it will (allegedly) reduce your top end. I think you should ride the bike regularly for three months so you have something to compare it too.

You really should replace the tires first anyway. Getting a blowout, even at 50 mph, on two wheels is probably going to hurt. Much more important than the 16T.