FSA stem warning (OS-115)(RD-120)
10-21-07, 09:33 AM
#1
The mods changed this...
Thread Starter
Join Date: Oct 2006
Posts: 2,346
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
FSA stem warning (OS-115)(RD-120)
If you ride these stems on a carbon steerer, pull it off and check your steerer tube. We've had 3 broken forks (at the steerer) due to these stems in the past 4 weeks. All on different bikes, but all with carbon steerers.
It seems that there isn't enough contact area between the stem and the steerer. The pressure of the stem when clamped to the steerer creates a pressure ridge and can crack the steerer tube. One we noticed when the stem itself broke and were changing it out. The other two sheared the steerer off completely.
All three stems were installed as instructed and torqued to FSA spec...
It seems that there isn't enough contact area between the stem and the steerer. The pressure of the stem when clamped to the steerer creates a pressure ridge and can crack the steerer tube. One we noticed when the stem itself broke and were changing it out. The other two sheared the steerer off completely.
All three stems were installed as instructed and torqued to FSA spec...
10-21-07, 10:00 AM
#2
Dirt-riding heretic
Join Date: Aug 2005
Location: Gig Harbor, WA
Posts: 17,413
Bikes: Lynskey R230/Red, Blue Triad SL/Red, Cannondale Scalpel 3/X9
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 5 Post(s)
Likes: 0
Liked 8 Times
in
7 Posts
Yeesh. Good to know. I have a Deda Newton on there right now, but I do have a spare FSA that I'll now be more reluctant to use...
__________________
"Unless he was racing there was no way he could match my speed."
"Unless he was racing there was no way he could match my speed."
10-21-07, 10:10 AM
#3
Banned
Join Date: Oct 2007
Posts: 7,468
Bikes: 2011 Cervelo S2, 2001Trek USPS 5200, 06 Cervelo P3 Alum, 1999 Schwinn Pro Stock BMX, 1987 Schwinn Traveler
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
Thats kinda scary. Imaging one breaking off on a 50mph decent. Bad news, and possibly career ending injuries. I am now reluctant to buy a carbon steerer fork too, even if it will only be used with my Syntace stem.
10-21-07, 10:40 AM
#4
The mods changed this...
Thread Starter
Join Date: Oct 2006
Posts: 2,346
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
If you have one, look at where the inside of the stem contacts the steerer. You'll notice that there isn't a large contact area...! When clamped, they seem to pinch versus distributing the pressure.
I hate to say it, but the only FSA products I've ever had luck with are headsets...
10-21-07, 11:06 AM
#6
The mods changed this...
Thread Starter
Join Date: Oct 2006
Posts: 2,346
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
The material inside of the stem, where the steerer passes through, is minimal. It has been designed that way for some strange reason. The only contact points are the very top and very bottom. There is NO material in the middle of the stem making contact with the steerer tube. Specialized stems have a sleeve so the steerer has constant, even pressure when the stem is tightened. Thomson also has a large contact area.
If you have one, it may be worth the 5 minutes it'll take to make the check...
If you have one, it may be worth the 5 minutes it'll take to make the check...
10-21-07, 11:18 AM
#8
Banned
Join Date: Oct 2007
Posts: 7,468
Bikes: 2011 Cervelo S2, 2001Trek USPS 5200, 06 Cervelo P3 Alum, 1999 Schwinn Pro Stock BMX, 1987 Schwinn Traveler
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
The material inside of the stem, where the steerer passes through, is minimal. It has been designed that way for some strange reason. The only contact points are the very top and very bottom. There is NO material in the middle of the stem making contact with the steerer tube. Specialized stems have a sleeve so the steerer has constant, even pressure when the stem is tightened. Thomson also has a large contact area.
If you have one, it may be worth the 5 minutes it'll take to make the check...
If you have one, it may be worth the 5 minutes it'll take to make the check...
10-21-07, 11:24 AM
#9
The mods changed this...
Thread Starter
Join Date: Oct 2006
Posts: 2,346
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
Obviously, yet they say nothing is wrong...
Here's a pic...
See the rear of the stem (inside)...you can see daylight. The upper clamp and the lower clamp are not connected in any way. All of the tightening force has to go through those two small (@8mm) surfaces. There is no real dissipation of the torque, other than the two highlighted areas.
See the Thomson X4...
The small amount of alu between the clamps is contact area and help to distribute the pressure on the steerer.
Here's a pic...
See the rear of the stem (inside)...you can see daylight. The upper clamp and the lower clamp are not connected in any way. All of the tightening force has to go through those two small (@8mm) surfaces. There is no real dissipation of the torque, other than the two highlighted areas.
See the Thomson X4...
The small amount of alu between the clamps is contact area and help to distribute the pressure on the steerer.
10-21-07, 11:41 AM
#10
Senior Member
Join Date: Jul 2006
Location: Raleigh, NC
Posts: 786
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 1 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
I'm sure it's light though. But their weight calculation probably doesn't take into account the sling you'll need for your shoulder after you launch headfirst over the bike.
10-21-07, 11:53 AM
#11
The mods changed this...
Thread Starter
Join Date: Oct 2006
Posts: 2,346
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
10-21-07, 01:35 PM
#12
Banned
Join Date: Oct 2007
Posts: 7,468
Bikes: 2011 Cervelo S2, 2001Trek USPS 5200, 06 Cervelo P3 Alum, 1999 Schwinn Pro Stock BMX, 1987 Schwinn Traveler
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
10-21-07, 01:43 PM
#13
Senior Member
Thanks for the FYI.
My Easton EM90 only has one clamp bolt area, but the sleeve covers the whole area over the steerer tube.
My buddy said he would never trust one bolt securing stem to steerer. I have 1200 miles on it with no problems.
My Easton EM90 only has one clamp bolt area, but the sleeve covers the whole area over the steerer tube.
My buddy said he would never trust one bolt securing stem to steerer. I have 1200 miles on it with no problems.
10-21-07, 02:23 PM
#14
Senior Member
Join Date: May 2007
Location: Seattle, Washington
Posts: 1,151
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
Thanks for the heads up. It seems that FSA has a lot of issues.
10-21-07, 05:36 PM
#15
The mods changed this...
Thread Starter
Join Date: Oct 2006
Posts: 2,346
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
10-21-07, 06:39 PM
#16
Senior Member
Join Date: Feb 2006
Location: Atlanta
Posts: 7,681
Bikes: Pedal Force QS3
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 1 Time
in
1 Post
The material inside of the stem, where the steerer passes through, is minimal. It has been designed that way for some strange reason. The only contact points are the very top and very bottom. There is NO material in the middle of the stem making contact with the steerer tube. Specialized stems have a sleeve so the steerer has constant, even pressure when the stem is tightened. Thomson also has a large contact area.
If you have one, it may be worth the 5 minutes it'll take to make the check...
If you have one, it may be worth the 5 minutes it'll take to make the check...
10-21-07, 06:48 PM
#17
Member
Join Date: Mar 2005
Posts: 36
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
Friends FSA stem cracked his carbon steerer tube ... that stems faceplate now serves another function as a modified "dogs tooth" on his MTB race rig. That being said ... it sure is lite! 
spatz
spatz
10-21-07, 06:54 PM
#18
James
Join Date: Jul 2007
Location: Fairfield County, CT
Posts: 484
Bikes: 2005 S-Works Roubaix Ultegra
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
The more and more I hear about and deal with FSA, the less and less I want to buy their product.
10-21-07, 07:02 PM
#19
A Little Bent
Join Date: Mar 2006
Location: Struggling up a hillside in Vermont, USA... ..........................................
Posts: 2,858
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 1 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
I have FSA 115 stems on all three of my bikes and a total of 5 hanging around the house...
Two of my three bikes have carbon steerer tubes...
I guess it is time to find some new stems...
Two of my three bikes have carbon steerer tubes...
I guess it is time to find some new stems...
__________________
10-21-07, 07:08 PM
#20
Banned
Join Date: Oct 2007
Posts: 7,468
Bikes: 2011 Cervelo S2, 2001Trek USPS 5200, 06 Cervelo P3 Alum, 1999 Schwinn Pro Stock BMX, 1987 Schwinn Traveler
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
10-21-07, 07:26 PM
#21
Senior Member
Join Date: Dec 2004
Location: Athens, Ohio
Posts: 5,104
Bikes: Custom Custom Custom
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 1 Post(s)
Likes: 0
Liked 1 Time
in
1 Post
i have a os-115 stem and i've had no problems with it on a carbon steerer. I'm not using it now, so i guess it might not get used anymore.
10-21-07, 08:42 PM
#22
Senior Member
Join Date: Jun 2007
Posts: 116
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
The material inside of the stem, where the steerer passes through, is minimal. It has been designed that way for some strange reason. The only contact points are the very top and very bottom. There is NO material in the middle of the stem making contact with the steerer tube. Specialized stems have a sleeve so the steerer has constant, even pressure when the stem is tightened. Thomson also has a large contact area.
If you have one, it may be worth the 5 minutes it'll take to make the check...
If you have one, it may be worth the 5 minutes it'll take to make the check...
Last edited by j.w; 10-21-07 at 08:48 PM.
10-21-07, 08:52 PM
#23
Senior Member
Join Date: May 2005
Posts: 6,900
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 3 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
Couple of things jump out. Assume the stems were all installed to the correct torque?
Isn't this something that should be reported to some government comsumer protection agency? American Classic had an entire hub recall over one faliure.
Isn't this something that should be reported to some government comsumer protection agency? American Classic had an entire hub recall over one faliure.
10-21-07, 09:30 PM
#24
CERVEL-LIZED!
Join Date: Dec 2006
Posts: 1,696
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
I ride the OS 110 but it has a full clamp on it meaning it doesn't have a hole on the clamp area so that there is a complete tightening area over the clamping surface. It is not the same design as the one pictured however it is not as light.
10-21-07, 10:47 PM
#25
Asleep at the bars
Join Date: May 2006
Location: San Francisco, CA and Treasure Island, FL
Posts: 1,743
Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 234 Post(s)
Liked 203 Times
in
135 Posts
Thanks for the info. I'm using an OS-115 on two of my bikes and an OS-150 on the third. I just ordered a Syntace F119 to swap out the one sitting on a CF steerer.