Dave I've found the exact opposite true with cold weather, especially with naturally aspirated vehicles - my camaro gets WAY more power when it's cold because the air is denser - I get more power with less throttle and especially when you are rolling around with 425 horses under the hood you notice changes in your gas mileage in a big way. I haven't done the homework on my own bike yet on a cold ride verses a hot day ride - I mostly don't like riding when it's cold.
You're absolutely correct Daryl about a vehicle having more power when it's cold.I've owned and built a number of rods over the years so I know exactly what ya mean.If fact,I built a couple Camaros just like yours for a couple guys I knew.One was a modified 350 and the other,a 427,both with close ratio Muncie 4 speeds,and then we had to go with to a 12 bolt posi rear end for traction,and then install ladder bars to keep the tires from bouncin.lol But both were fun projects.
Anyways,getting back to the subject at hand,lol that's because the mixture LEANS out.The colder it gets,the leaner it gets and the better the vehicle will run.However,when it's first started,is when extra fuel is needed until she warms up.Now notice I said in my post"the mileage will drop off SOMEWHAT".I didn't say the mileage would be poor.lol But the increase in power in cold weather is DEFINITLY noticeable.
Ya wanna talk about incresed power,try takin your bike out when the temp gets into the teens,single numbers,or below.The colder,the better.You'll swear you're drivin a different motorcycle altogether.lol It's almost as if the HP has doubled.lol The coldest I've driven a two wheeler in,is minus 25*F.The machine pulled strong as hell.However, my body didn't wanna pull very well.lol lol Dave!!!