LOL, well, you can always pack on a few more pounds, LOL. Kidding. Smaller gun or simply not care that anyone notices that you are carrying a 1911. And since you are in AZ....you can open carry, right? That may be an option when riding.
That's what I really liked about the M&P series from S&W: they're about the same size as a 40 caliber / 9mm but it's still a 45. The grip is just a tad shorter and the barrel is just a bit shorter. Not much, but it does make a difference.