Complex sentence: As well as bicycles Hillman's company made roller-skates, sewing machines, and ball and roller bearings, of which it pioneered the mass production; Hillman was soon operating four factories in Coventry, and by 1896 a fifth in Germany.
Split into simpler sentences: As well as bicycles Hillman's company made roller-skates, sewing machines, and ball and roller bearings, of which it pioneered the mass production. So successful was the enterprise that Hillman was soon operating four factories in Coventry, and by 1896 a fifth in Germany.