AS Schwinn Stem/Handlebar Binder Bolt

[atencioee]

Any experts know the years these round head "AS" stem binder bolts were used on the Phantom?
Correct me if I'm wrong...some Phantoms originally came with these and some came with the regular hexagon non-stamped head?

 

[Brutuskend]

wondered that myself.

We are waiting!!

 

[GTs58]

In my observations I've seen those keyed bolts mostly on the early Phantoms thru the 52 model year and the vast majority of the 53 and later models had the hex bolt. That keyed stem and bolt goes back to at least the later half of the 30's.

 

[mr.cycleplane]

the earliest version of the stem pictured above started in 1936.