Great vid. There's no denying those speeds are fun - and it feels extremely free and liberating (if slightly naughty !) and the force of the wind is very significant. On anything but a hot Summer day it's probably going to be freezing. He makes some good honest points too about how he feels riding it - like wanting mirrors and cars not expecting you to be going at >30mph.
It's amazing how your perception of speed differs when you're on a bike vs say in a car. You can barely feel the difference between 30 & 40mph in a car and everything slower around you looks really slow. It can feel like a crawl. But break 30mph on a bike and it starts feeling exhilarating. Break 40mph and it's a serious rush - everything to the sides is just a blur. Reach nearly 50mph and your mind starts churning over whether you checked your brake pads are in good nick, whether you paid up your life insurance, hoping to **** you don't hit any bumps, potholes, cracked up road etc. and realizing you really should be wearing a proper helmet ! It goes from fast to seriously fast to the extent your danger awareness is on red alert .... and turning round to check behind whilst riding at that speed is not ideal at all.
Having a car cross a solid white line to overtake you (with about 1.5m of clearance), then pull back in front of you to avoid an oncoming car and brake hard when you're doing 45mph on a bike just short of a 40mph zone is enough to make caution kick back in (in earnest). This happened to me twice riding down steep hills on the Trek over the Summer. I basically realized the trouble is car drivers are often extremely impatient types whose only priority is to get ahead of you as soon as they possibly can, even when you're cycling at or over the speed limit. I can imagine you'd find the same riding on the flat under throttle. They have no empathy whatsoever with the factors you're dealing with on a bike. Roadie racers basically deal with this by riding in packs and this helps to some extent. On an e-Bike you're on your own so you have to be really careful imho.
On anything but clear open roads with long distance forward visibility this tendency of car drivers is a recipe for potential big trouble at speed. My downhill sprints (supposed to be my rewards for working hard up hills) got scuppered to crawls behind braking cars or farm vehicles far more often than I got to enjoy the rush of a fast ride. So when the conditions allowed to let it all go I took full advantage
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