 At the end of this year the BB and CB models were discontinued.The 350cc DB32 continued in production until 1962.The 500 cc DBD34 was introduced in 1956, with clip-on handlebars, a finned alloy engine with a newly designed head, chrome plated fuel tank, 38 mm ( 1 1/2" ) bell-mouth Amal carburettor and swept-back exhaust.