I'm writing you from hot hot Japan right now, trying not to melt, so this is a short one from me.
Japan's cycling culture is waaay different to the UK's. It's completely normal here for anyone of any age to pootle about town. They mostly ride what's known as a "mamachari"; the word comes from "mama chariot". Shortening words here is a national pastime (i.e. pokemon means pocket monster and Godzilla is gorilla + kujira [whale]). The bikes are super comfy to ride, usually have a basket and rear rack (or even seats for kids), and nobody, but nobody, wears hi-viz/lycra/helments. People ride on the pavement and on the road, and there is no cycling infrastructure in place, just respect for one another. It’s refreshing, lemme tell ya.
BTW you can get mamachari bikes here in London at - you guessed it -Mamachari Bikes in Dalston. Headed up by the lovely Noah and Ran, they import bikes from Japan and get them ready to ride here in the Big Smoke. They are affordable, bullet-proof, and low maintenance. I highly recommend the bikes and the shop. I want one!