This should explain it I think you are thinking of the extended warranty that you buy is 4 years. Its nice to have a warranty if something big happens but other than that I doubt I would ever use it. I don't trust the dealer mechanics to touch my bike.
I have a 14 and its the same for the 15 also
http://powersports.honda.com/protectionplan/motorcycle-threeyear.aspxMotorcycles
3-Year Warranty
Includes Touring, Sport Touring and selected Cruisers
Nationwide Coverage
Covered repairs may be performed at any authorized Honda Motorcycle/ATV Dealership within the United States, including Hawaii and Alaska.
No Mileage Limitation
No need to watch your odometer. Coverage will not expire at any pre-set mileage limit.
No Deductible
Not one penny will come out of your pocket to pay for repairs covered by HondaCare®.
Transferable
Coverage is transferable to the next owner of your vehicle at no additional cost.
This chart shows the maximum coverage available with a Honda Protection Plan. You can extend your coverage by an additional four years — for a combined total of seven years.*