What was the phenomenon called when a rider on a high-wheel bike was thrown headfirst over the handlebars?

Answer

Taking a header.

When the front wheel of the high-wheel struck an obstruction, the machine would pitch forward instantly, resulting in the rider being thrown headfirst over the handlebars, a phenomenon termed 'taking a header'.

What was the phenomenon called when a rider on a high-wheel bike was thrown headfirst over the handlebars?
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