For clarification on terminology, when you say solenoid, I assume you are referring to the "Starter Relay Switch" to the right of the battery (to use Honda's terminology from the manuals)? Not trying to say "nyah nyah, you're wrong" just trying to make sure I know which parts we're talking about.Went out this morning and the bike wouldnt start. So I tested the battery it was 12.8ish dropped to 11.8ish when hitting the switch. This is a normal range for the bike when it starts with no issues. It was really cold and I had to head to work so I couldnt pull the solenoid to clean it. Instead I tested it by carefully bridging the poles and it started right up. It started all day after that with no issues.
Back in March the last thing I did before the problem seemed to be fixed was pull the solenoid spray it with cleaner and wire brush it. That seemed to be the end of the issue until now.
So based on this it seems like maybe bad contact on the solenoid? or something when cold causing it to not work every time? Could something before or after the solenoid be the issue? It seems like the starter works when the solenoid does and the battery has enough juice.
Like bigbird said, 'mechanical' problems are sounding more likely than 'electrical' problems*
Bridging the poles worked, so it's probable you have a sticky (or failed/failing) relay (either the "Starter Relay Switch" or the "Starter Relay").
A sticky starter could also be the cause, but I would have thought you'd have no change when bridging the poles. Where it's intermittent, we shouldn't necessarily rule it out.
As far as temperature dependency, anything that's mechanically sticky is likely to be worse in lower temperatures. Viscosities tend to increase with temperature decreases, so contamination is likely to have a greater impact.
NOTE: Bridging the poles has the effect of removing both relays and the PCM from the circuit, so the other possibilities (though perhaps unlikely) would be a toasted PCM or problems with interlock switches. Sidestand and N switches should affect starting. Not sure if the tip switch affects the starter motor on the DCT models, but it does not affect the starter motor (but does cut fuel and spark) on the Manual models. Where the DCT models just feed all interlock information to the PCM, I can't accurately determine which interlocks affect which systems from the information I have so it's a bit of an educated guess.
My next troubleshooting steps if I were you would be to pull the battery/maintenance cover inside the Frunk and locate both start-related relays and listen for both clicking when pressing start (starting with the Starter Relay on the fuse panel, and then the Starter Switch Relay common to the main fuse). I'd probably reseat the relay on the panel, just to be sure as sometimes things can wiggle loose. Check and clean (as required) the Starter Relay Switch, and perhaps seal on reassembly if it looks like grime or moisture is getting in.
If both relays seem good, I'd check the condition of the start motor. The case has a seal between each cap and the main body, and there are O-rings at both the positive terminal-to-case and around the shaft-to-motor. Unlikely based on the symptoms, but it's possible your start motor is gunked up. Even if all seals are good, there could be residue from worn brushes inside the case, so if you get to this point, it might be worth opening up the motor and cleaning.
*SIDE NOTE: At work, we have a few electrical guys that seem to go out of their way to turn "electrical" problems into mechanical problems. This sounds like one of those cases, where the "electrical" system isn't working, but it's due to the mechanical failure of an electrical component such as a relay. Everything would work fine electrically if the failed (or contaminated) component worked mechanically. In their mind, EVERYTHING is a mechanical failure...