Most of the time cyclists are doing speeds around 15 - 30 mph. Motorcycle helmets are safer. But they also limit your senses which is more detrimental at low speeds while riding in traffic than having slightly more protection.
In motorcycle world there's a lot of contention about protective gear. From people that ride without helmets in shorts and t-shirts everywhere they go. To people that put on every piece of gear no matter where they go. It's an almost religious topic and people can't see nuance. If you're riding around in town and not going above 40 km/h there's honestly no need for a full face helmet and all the protective gear, but it also doesn't hurt. Good shoes and gloves are the most important safety equipment for any 2 wheeled vehicle, be it a motorcycle or a bicycle. I'll never ride anything two wheeled without good shoes and gloves, because those are the first things that will make contact with the ground when you take a tumble. After that comes helmet and then more protective gear.
If you're only doing a downhill KOM run where you're expecting high speeds and taking risks you probably should wear some protective gear on a bicycle. It's not pretty if you fall at 80 - 90 km/h while wearing nothing but spandex. But if that downhill is going to be a small part of your ride and you're being careful and not pushing it then the chances of falling are so low that wearing more protection isn't necessary even if you momentarily rech high speeds.
>>1881818Any monkey can reach 80 - 90 km/h on descents. And pretty much any motorbike will have supercar acceleration, doesn't have to be a turbo busa.
