Preface: I'm not a chemical engineer.
Facts: There are many motorcycles (and cars) with 100K+ miles , that have never seen a drop of synthetic. Most people relinquish ownership WAYYY before they ever encounter any engine problem that would even be remotely related to wear-- that could be traced to oil quality problem, when oil was changed appropriately. Many motor problems are related to "other" mechanical issues that may cause wear due to: internal collision, improper oil flow, timing/cam chain issue, etc.... but not related to oil type (synthetic vs. non-synthetic).
Opinion: This boils down to opinion, like many other things. Without veering off course (too far), from your original inquiry, any good synthetic (with adequate specs/viscosity) should be fine for your described use. The 2,500 miles that you ride, should be no issue for an appropriately matched synthetic. Personally, I don't prefer to use any oil for more than 6 months due to the contaminants that collect, which is a totally other factor. Many of my current/recent motorcycles in past years have only required a little over 2 quarts to refill (oil change is relatively inexpensive anyway). I also ride less than 3,000k miles/yr, and have for many years-- busy guy! For my peace of mind (in normal operating conditions), my preference is to change every 6 months but wouldn't loose sleep if I waited up to 12 months (in normal operating conditions). I feel confident in this approach using non-synthetic and certainly would be confident in this approach with synthetic.
Some related info:
Time (not mileage) between oil changes | Passenger Car Motor Oil (PCMO) - Gasoline Cars/Pickups/Vans/SUVs | Bob Is The Oil Guy
Top 7 Urban Legends About Motor Oil
For an oil change that only requires a little over 2 quarts, only stays in bike for 12 months, and is proposed to use synthetic, my vote would also be the (cheaper) synthetic 5w/40 Rotella as waltermitty suggested-- even though the Rotella non-synthetic would probably protect just as well in the conditions that you describe.
Unrelated: A friend of mine owned a SR500 for close to 25 years and 70k miles. It's an air-cooled single-cylinder engine that shears/stresses oil. He rode the bike relatively hard, changed the oil once/twice per year, and used non-synthetic oil for the duration (whatever brand was handy). The bike still ran strong when he sold it. Just goes to show that it's important to change the oil periodically, but in 25 years of use, it's not necessary to use synthetic.
Been lots of great threads on the quality ratings and detailed viscosity specs for motor oil. Instead of reviving those great comments, thought I would ask a couple of basic questions.
Why the huge price spread between some of the synthetics? ($6 - $16/quart)
Trying to give business to a local shop vs. Wally World, I bought AMS 10W-40 MC synthetic last year at a price of $12/quart. Should I just use one of the more popular mass produced brands for half the cost?
What milage frequency do you change at?
If only putting on 2,500 miles per year, would you change at the end or the beginning of the season? I do sneak in an occasional winter ride.