Viking 'SBU' Tracker - 1954

“looking through Cycling’s in 1954 I came across details of a Viking track machine known as the ‘Viking S.B.U. Tracker’ – 1954. In the Cycling road test they state: “SBU (Short-Wheelbase Underslung) design was arrived at after extensive research into lateral and torsional twisting stresses. As you can see, there are two pairs of chainstays, an upper and a lower, and the down tube extends down beyond the bottom-bracket for an estimated 28cm.” Viking state that “The SBU separates the two stresses and concentrates each at a different point”. Originally, in 1953, this frame only had the lower chainstays but the upper ones were introduced in 1954 – it should have been obvious that a big open quadrilateral would be more flexible than a smaller triangle but maybe the idea was to save weight.   The bottom-bracket is in a lug behind the junction of the down and seat tubes, giving a short rear triangle of 16″. The 1954 specification was: Brampton Alatet headset, Baylis Wiley ‘Featherweight’ bottom-bracket, Williams 5-pin inch-pitch chainset with Italian Noli and Catteano quill pedals.  Christophe toeclips with AL-E straps.  Brooks B17 Narrow or Sprinter.  Wheels had Weinmann ‘Scherens’ sprint rims on Airlite LF hubs fitted with Cyclo domed track-nuts.  Cinelli bars and stem with 15½” ‘Gran Fondo’ deep drops.”

For more information on the Viking Cycle Company visit http://www.localhistory.scit.wlv.ac.uk/Museum/Transport/bicycles/Viking.htm