Some items from this specific schematic: Tube,z.75/3.00-21,tr6, Tire,rr,5.10-18 4pr,k, Spoke-inner,rr,lh,199, Tube,4.50/5.10-18.
With seventy-two applications this Nipple-spoke is the most specified part.
Of all the components used in this assembly the Rim,rr,2.15x18 is the most expensive.