We need to go back to the first Stingray strut to understand a few things about the High Loop and it’s design.
Here is solid information I’ve accumulated over the decades pertaining to the 63-64 square back PERSONS strut and the 64-1/2 thru 1965 High Loops.
The first two photos are low resolution that I took maybe 20+ years ago showing the progression of the square back struts.
The 1963 Schwinn Stingray had a strut without a crimp at the Q-bolt hole and a very small round drain hole at the bottom. This strut is also found on the early 1964 models.
Later in 1964 these struts had a large crimp at the Q-bolt hole area to make for a much stronger design.
The last square back strut design now had a vertical rectangle drain hole at the bottom. This style of drain hole continued on the majority of the High Loop strut.
The last four photos are of an NOS late ‘64 strut with the large crimp and a new design drain hole.
PS, notice on the very first 1963 strut there is a PAT. PENDING stamp at the bottom.
This strut was only used on the early Stingray models.
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