The frame had the loop as far back as the k model days. it was originally used to mount the steering damper. i myself am also curious about when they started to add the lock tab to the lower tree. they still used the steering damper in 1966, so the tree wouldn't have had the lock tab. both of my '69 xlch's have the lock tab. so they added it sometime between 1966 and 1969. hopefully someone has the answer because i am restoring a 1967 xlch and need to know if my lower tree needs the lock tab. i suspect it was added sometime in 1967.
Been scouring the parts books and the 54-65 K/Sportster book shows a -54A tree without. The 54-78 book shows 70 and earlier front end as a separate piece called "Fork Lock Bracket" with part number of 45724-68A. Seems as if it is a bolt or weld on piece. The 71-72 front end shows that too. As well as the 73-74 too. Plus the 75 up.
Think Magneto Sportster is pretty close with 67 or 68 being the year based on the part number ending in 68A.
So in summary the my 62 project is proper without.
Not sure why the 69s have it for security...They already have a Tillotson.
Yes, that's the correct triple tree for your bike. Magneto, I will go look at my 68 and see if the triple tree has the lock tab as soon as this freakin' rain stops! (It's been raining here for about a month and a half).
If I could only live at the pitch that is near madness
When everything is as it was in my childhood
Violent, vivid, and of infinite possiblilty:
That the sun and moon broke over my head.--Richard Eberhart