No issues, unless your planning to finish a 3K mile road trip with the spare. A smaller tire can cause uneven wear on the tire at the other end of the axle.. Not an issue if you get the 16" tire fixed/replaced.
I'm doing the same thing this year, and keeping both of my spares 15".
LarryJM wrote:
While you could probably put a tire one size smaller on one side of a tandem TT you will probably overload the other tire to the point of damaging it beyond the point of it being reliable and necessitating replacement of that tire in addition to the other smaller tire sooner than later.
Larry
Your going to have to get some scale slips to prove that one....
The suspension of a tandem axle will keep the load much closer than you think.
