Why are you so worried about what the temperature gauge reads. if you are worried about freezing, being a few degrees off that low, is not going to help much anyways if you are that cold already.
You also have to remember these sensors are not hanging out in open air just flapping in the breeze. If there is any sunlight or any light really on the bike, it's going to convert some of that into heat, which will be trapped with the bike until you get the air circulating so it's fresh and the temperatures are back closer to normal. Just like its hot in your car with the windows rolled up, because of the lack of airflow.
Plastic gets hot in the sun, and can radiate that back out as heat.
With this though, that might be a nice little 'tweak' that Energica could add is an offset menu for the temperature so the user can adjust it up or down, say, 10 degrees or so to make it where they are happy with it.
Honestly should not be too hard at all to implement, just one or two logic blocks really. Input A thermometer, input B, user offset, add them and output.
Aaron