Yeah, you probably need a new oil pump.
Our 97 600 twin is in the shop right now. Our dealer previously told us that our particular sled would be covered under warranty, and now we are trying to make them stick to that. Even if they over the part, the labor, or even lets say 50 dollars off I would be more than happy. See if your dealer will cover it. They might.
The oil pump retails for 140 dollars or so.....
Our dealer is a little ignorant, not knowing yamaha has had a pretty widespread issue on these oil pumps, to the point that they changed the part # for 98, and if you try to look up the oil pump, you will see a superceded part. The original ones failed a lot, and they fail to put too much oil in. This particular dealer was not even around in 97, or 98 for that matter, so I don't expect them to know off the top of their head.
I think if I get 200 miles from a set of plugs before they foul out I am lucky. ps, my carbs have been cleaned, and the smart carbs work as they should.