After seeing in person all of Jim Lokie's Simplex truck tow bars and Bob legron's at Portland Bill Erikson sent me pictures of the tow bar on his truck and looking at every picture that I could find I have pretty much come to the conclusion that my tow bar is the same tow bar that was offered as a option for a two wheeled Simplex...as seen in this picture/magazine ad that I included-it is identical! As is the welded on tow bar brackets that are welded to the forks And the way it is designed it would keep a two wheeled bike in the vertical position when being towed behind a car... it also utilizes a universal mount that can be mounted to any 50's car bumper, The other type tow bars utilize a tow bar that needs a trailer ball to attach the tow bar to the car. Mine is missing one of the mounting rods that tightened and hold the tow bar to the bumper and also a part that hooks over the top of the bumper, but I have found one of those I just don't have a pic of it yet I will add it when I can. The first pic is 1952 the last 3 are from a 1954 Speigal catalog ad. Simplex was defiantly not consistent from year to year and made a lot of changes on the fly along with the parts they used, and what was installed from year to year when putting these bikes together!
