I recently got a nice 3TTT stem that's a Cinelli XA clone that doesn't have the stress riser relief circles on the steerer plug slot. I'm just wondering if this is going to have the same problem as the infamous Ava death stem that came on all those UO8's and French bicycle's?

I'd really like to use this stem because I like the XA stem's looks but don't like the handlebar ridges inside the clamp nor do I like the pinhole in the front where the button logo attaches on the front. And you never know if someone tried to clamp a 26.0 handlebar in a 26.4 stem making it even worse of an issue... Too many stress risers for a vintage quill stem at this late stage of a stem's life or mine either. But this has none of that, so I'd like to use it if possible.

The el cheapo-cheapo cast AVA stems and other clones from 50+ years ago have almost nothing in common with the stem you show.

I used similiar forged Cinelli and 3T stems for 20+ years and never had a single problem with not having a round hole at the end of the expander slot. That seems to be a real nervous-nelly Bike Forums fetish, though.

Then again, how hard is it to simply drill a small hole or use a small round file at the end of the slot ?

that's what I did for my GB stem on my Raleigh International...



Not hard at all.
I may have used a chainsaw file after making a hole with a small drill.
It's cheap insurance, even if there is a very low chance of having a stem crack at a corner of one of those slots.

Steve in Peoria

I have never heard of a crash, much less a death, from cracks that started at those slits. Even if the crack progessed all the way around, there's still a steel bolt holding the top and bottom halves together.

I think it's a tempest in a teapot.

You want death stems?






Sorry about the focus on the last one; it's a Rivendell-Nitto lugged steel, handlebar clamp end just fell off.

Ah, this pic shows it better:



Stop worrying about the expander slits and start worrying about every single other place on a stem!

.

Thank you for your help. I don't have anyone cycling savvy that I can ask that wouldn't just try and sell me a new bike...

I actually had an AVA stem crack on my first road bike at the plug slit and I almost turned right into a parked car on a busy street. I still fell though and it sucked. This was 45 pounds less and decades ago too. So I'm a little antsy about this. Other than that I've never had a stem break.

I also cast a careful eye at those 3TTT slits. Notice that the slit does not end abruptly; the metal at the inside of the slit angles out toward the outer edge of the seatpost. (You can just see the angled bit at the top of the slit in the OP's photo). Seems to me that this diminishes the stress risers that the old AVA and other stems had.

Things happen.
was a unique stem.
abused in many ways I think.


cue the old David Bowie song with the crack lyric

They all have that "angle", really an arc; it's what you get with a slitting saw which is circular.
And *all* such stems get (from me) holes at the tops of their slots.

most notably, the AVA and Pivo stems were cast Aluminium, the 3T ones are forged. totally different wheelhouse.
If you are still worried, it is no problem to add the stress relieve hole yourself, as long as you are meticulous about deburring.

Yeesh, Mark; that's scary. Can I ask what kind of stem this is/was, or whether it was a one-off? I like the idea of a fillet-brazed stem, but...

That's an Ibis, TIG-welded Ti alloy.
Most of them are good, this one apparnetly had a bad weld. Too little penetration, or bad prep or argon shielding, we'll never know.

Scary? Well, it's in an extremely noticeable spot, so unless it snapped off from a one-time event (unlikely), the crack probably would give lots of warning, growing slowly at first. Not as insidious as fatigue cracks that grow in a place that you can't see until it's too late.