I bought an ebike a couple of years ago and find that while it may have a somewhat higher carbon footprint, things like heat and air quality have been less of an issue and I commute most days on it now. This is not just because you can switch to an all-electric ride and enjoy the breeze without the workout. In my experience, it also encourages you to seek out parks and trails which may be hillier or add a bit of distance, but are often cooler due to more shade, proximity to water, and less asphalt everywhere.

There are some steps you can take to stay cool on any bike though. There are all sorts of neck and wrist coolers on the market, but even tying a wet towel around your neck can make a huge difference. I am prone to heat exhaustion and this has saved me even when just walking around. But on a bike where you have a breeze to boost the cooling effect of having something wet on your body, it works really well.