Holy Zombie Thread Resurrection!
Seriously and as a commuter into DC for decades, I've ridden both of my Super Teneres (2012 & 2014) into single digit temps many times and the bike did just fine. It actually seems to feel better the further it gets away from the raw wet cold near the freezing mark, but maybe that was just me. I was super vigilant about road ice, especially on Canal Road which gets run-off. Car drivers seemed a bit more tolerant of the guy on the motorcycle and it was fun to see co-workers faces as I walked in looking like an astronaut.
Note that the owners manual provides a range of oil viscosities which get thinner for cold temps. It makes a difference in how quick the engine will turn over to start.
Of course the AGM batteries are less capable in the cold and these bikes
really need good voltage (minimal voltage drop) to the ECU when the starter is turning, so make sure the battery is in good shape. It's also the first thing to suspect if starting is a problem. I'm not big on recommending lithium batteries, and this is especially true for sub-freezing temps.
As for gas mileage, yes there is the mixture issue mentioned previously, but the bigger factor is that Winter gas as refineries change the Reid Vapor Pressure (RVP) which controls the rate of evaporation. Evaporation is closely related to atomization of the fuel droplets so the engine loses a bit of performance and mileage suffers.
As temperatures increase into the summer months, government regulations dictate the type of gasoline we use in our vehicles. Summer Blend During the summertime, gasoline has a greater chance of evaporating from a vehicles fuel system. This can produce smog and increase emissions. Refiners...
www.guttmanenergy.com