Modolo X-Tenos stem question

George said:

What is an exact clamp diameter of the black Modolo X-
Tenos stem? I try to use it with my ITM 25.8 mm handlebar,
but it seems to be too tight :-( Regards, George.

Diameter should be the same, but BEWARE! The X-Tenos stem is
notoriously prone to sudden catastrophic failure. I strongly
advise against using this dangerous product.

See: bikexprt.comstems.htmOpen ↗
for details.

Sheldon "Ouch!" Brown +-----------------------------------------------------
+
| We can complain because rose bushes have thorns, | or
| rejoice because thorn bushes have roses. | --Abraham
| Lincoln |
+-----------------------------------------------------+
Harris Cyclery, West Newton, Massachusetts Phone 617-244-
9772 FAX 617-244-1041 harriscyclery.comharriscyclery.comOpen ↗ Hard-to-find
parts shipped Worldwide captainbike.comcaptainbike.comOpen ↗
sheldonbrown.comsheldonbrown.comOpen ↗

In article <[email hidden]>,
[email hidden] says...

Quoted message said:

George said:

What is an exact clamp diameter of the black Modolo X-
Tenos stem? I try to use it with my ITM 25.8 mm
handlebar, but it seems to be too tight :-( Regards,
George.

Diameter should be the same, but BEWARE! The X-Tenos stem
is notoriously prone to sudden catastrophic failure. I
strongly advise against using this dangerous product.

I had one of these stems and very luckily caught the damage
before it completely cracked through. You can do a visual
inspection of the stemp, mine was half way to breaking when
I caught it. Look at the stem from the bottom. Look at the
area around the bolt hole, that is where the cracks start.
--------------
Alex

Alex Rodriguez <[email hidden]> wrote in message news:<[email hidden]>...

Quoted message said:

In article <[email hidden]>,
[email hidden] says...

Quoted message said:

George said:

What is an exact clamp diameter of the black Modolo X-
Tenos stem? I try to use it with my ITM 25.8 mm
handlebar, but it seems to be too tight :-( Regards,
George.

Diameter should be the same, but BEWARE! The X-Tenos stem
is notoriously prone to sudden catastrophic failure. I
strongly advise against using this dangerous product.

I had one of these stems and very luckily caught the
damage before it completely cracked through. You can do a
visual inspection of the stemp, mine was half way to
breaking when I caught it. Look at the stem from the
bottom. Look at the area around the bolt hole, that is
where the cracks start.
--------------
Alex

Man, I didn't know about this sort of failure. I have an X-
Tenos on my rain bike, left over from many years ago. There
were problems with these things right from the begining and
Modolo sent me 7 or 8 stems until I got one that was ok.

But here's the thing. I had a near catastrophic event with
this stem about a month and a half ago. While sprinting up
hill the handle bar bolt failed at the head to bolt body
transition and the bars immediately rotated giving me quite
a scare. Very nearly lost it. I've replaced the bolt from
one of the other stems, but now I'll replace the stem. I've
broken to many bones as a result of equipment failure.

Thanks for the heads up!

Curious, I have an X-Tenos on one of my road bikes and and
X-EOS (a predecessor) on my training bike and have had
trouble free service from both for many years. I am no small
guy either! Too bad they had problems, they were sure
beautiful to look at. I have at least 25,000 miles on the
X-Tenos bar/stem combination. I do recall that the stem
didn't tighten quite as well as it should have on non-Modolo
X-Tenos bars.

Terry (still ridin'it but now checkin'it) Rudd

JZWest said:

Alex Rodriguez <[email hidden]> wrote in message
news:<[email hidden]>...

Quoted message said:

In article <[email hidden]>,
[email hidden] says...

Quoted message said:

George wrote:

>What is an exact clamp diameter of the black Modolo X-
>Tenos stem? I try to use it with my ITM 25.8 mm
>handlebar, but it seems to be too tight :-( Regards,
>George.

Diameter should be the same, but BEWARE! The X-Tenos stem
is notoriously prone to sudden catastrophic failure. I
strongly advise against using this dangerous product.

I had one of these stems and very luckily caught the
damage before it completely cracked through. You can do a
visual inspection of the stemp, mine was half way to
breaking when I caught it. Look at the stem from the
bottom. Look at the area around the bolt hole, that is
where the cracks start.
--------------
Alex

Man, I didn't know about this sort of failure. I have an
X-Tenos on my rain bike, left over from many years ago.
There were problems with these things right from the
begining and Modolo sent me 7 or 8 stems until I got one
that was ok.

But here's the thing. I had a near catastrophic event with
this stem about a month and a half ago. While sprinting up
hill the handle bar bolt failed at the head to bolt body
transition and the bars immediately rotated giving me
quite a scare. Very nearly lost it. I've replaced the bolt
from one of the other stems, but now I'll replace the
stem. I've broken to many bones as a result of equipment
failure.

Thanks for the heads up!

Sheldon Brown said:

Diameter should be the same, but BEWARE! The X-Tenos stem
is notoriously prone to sudden catastrophic failure. I
strongly advise against using this dangerous product.

Quoted message said:

See: bikexprt.comstems.htmOpen ↗ for
details.

Eeek. The Modolo Q-race stem is similar looking but has the
bar clamp bolt enter from the top, rather than the bottom.
That means there is a much smaller diameter hole in the
extension, although it's still a fairly small cross-section
to trust one's face to.

Many many stems that look like the Cinelli XA have a clamp
bolt behind the extension, but again the load bearing part
only has to be tapped for the bolt thread diameter. Also, in
the distant past of mountain biking, lots of stems had small
diameter holes to serve as a canti brake cable stop. One
hopes that the X-Tenos stem was close to unique in its
monobuttocked design.

I'm not sure I totally agree with this URL. It suggests that
all "flawed stems [are] split behind the handlebars".

I think the X-tenos may have been a bad design. But how do
you explain all of the other stems with the split in the
same area: Deda Murex, TTT 84, TTT Motus, Cinelli Grammo,
Performance Forte Classic and so on? Are they all accidents
waiting to happen?

-Dion

Quoted message said:

Sheldon Brown said:

Diameter should be the same, but BEWARE! The X-Tenos
stem is notoriously prone to sudden catastrophic
failure. I strongly advise against using this dangerous
product.

Quoted message said:

See: bikexprt.comstems.htmOpen ↗
for details.

In article <siNac.47973$gA5.618653@attbi_s03>, TR-I-
[email hidden] says...

Quoted message said:

Curious, I have an X-Tenos on one of my road bikes and and
X-EOS (a predecessor) on my training bike and have had
trouble free service from both for many years. I am no
small guy either! Too bad they had problems, they were sure
beautiful to look at. I have at least 25,000 miles on the
X-Tenos bar/stem combination. I do recall that the stem
didn't tighten quite as well as it should have on non-
Modolo X-Tenos bars.

I wasn't a big guy back when I got the stem, ~140 lbs. It
still cracked on me. Definitely a defect in the design. They
were good looking stems. The stems that followed were not as
attractive.
--------------
Alex