By 1870, metalworking had improved to the point that bicycles began to be constructed entirely of metal, an improvement in both performance and material strength, and bike design began to change accordingly. The pedals were still attached directly to the front wheel but solid rubber tires and long spokes on a much large front wheel provided a greatly improved ride. Also, the bigger the wheels, the faster you could go, and the Penny Farthing as they were called enjoyed a great popularity in the Europe and the United States in the 1870s and 1880s.
The main hazard to this design was its (un)safety factor, as the riders (usually young men) sat so high up that they were very vulnerable to road hazards. The braking mechanism was almost more symbolic than functional, and there was really no way to slow the bike. And, if something were to stop the front wheel suddenly, such as a rut or object stuck in the spokes, the rider was immediately bucked forward as he rotated up over the front wheel to land squarely on his head. Hence the origin of the term “breakneck speed,” since a crash often produced truly devastating results.