Originally Posted by
obuckler
Response to above. There are plenty of photos above that will show the crack location.
Yes, I saw the pictures. But I want to know where the stem cracked that caused the handlebars to come off. Your crack can't really cause that at the moment, even if it goes clear through to the bolt hole. I want to know where hypothetical further cracks might start, if
JohnDThompson might care to tell us how it looked after the bars came off on his tour. Perhaps the crack he experienced started someplace else.
Interestingly, it is known that the Cinelli 1E stem, which was designed to have a front-facing reflector bolted on the back, had a tendency to develop a crack similar to the one you show here, if the reflector was removed, because the tapered hole in the backside was not reamed large enough to accommodate the increased depth/diameter of the knurled nut sans reflector. Yet another way CPSC
ruined changed things in the '70s.
My 1A with a similar crack to yours does, indeed, have an aftermarket nut - one of those Arnold Industries ultralightweight jobs. I think that's why mine cracked. It sounds an awful lot like the "non-critical" cracks mentioned by S. Barber on Velobase. Still riding it though - I'll post a picture tomorrow as the capstone of my dissenting opinion, and then I will shut up about it...