Rotor Stems- The good and the bad

[KWalker]

I searched around found a lot of posts about the Rotor stems being light, but I was specifically interested in their stiffness, and their bolt/faceplate design. The S2 looks to have a 2 bolt design and I would worry about faceplate stiffness, whereas I haven't seen the S3 on anything. Anyone have any comments. This has become an attractive option when compared to my Deda Zero 100

[Stolichnaya]

Not sure I am diggin' the one steerer tube bolt design on this one.
If the stem is as light as claimed (and Rotor is ususally pretty good about theuir claimed weights from what I gather) then adding one extra steerer tube bolt would not have been a big penalty, but a big leap in (psycological) security.

[Mario Jr.]

It's not an normal bolt, but one of Rotors DTT bolts which has treads on both sides. This enables the stem to be designed to be tight around the steerer without any bolts at all. The DTT bolt opens the stem instead for installation and does not need to be tightned much afterwards. The benefit is that there's no bolt sitting with a lot of tension constantly which will cause the stem to fatigue. Also, the DTT bolt forces the stem to close more linear so no dents are left in the steerer tube. You should look at the new S3X stem. That is a very light and stiff stem which exceeds any durability standard incl. Efbe.

[KWalker]

Has anyone tried their newer stem, the S3 I believe its called?

[jipperd]

The S1 series weren't that good, bar slipping happened quite regularly, mine slipped one time after that it luckily didn't anymore. The S2, which I own 1 as well, where better, they clamp very good and it's a typical fit and forget stem. I have my personal doubts about the S3 single bolt design as well. As for the availability of the S3 stem, it isn't available yet.

[Mario Jr.]

The S3X stem, as it's called, is indeed available in most lengths.

No need to worry about the one bolt. The clamp strength is a lot higher on the DTT bolts than on normal bolts. The one bolt distributes the clamping force better, too.

I have used one on my MTB for two months now, with no problems at all.

[KWalker]

And what stem would you equate the stiffness too? It has to be no less noodly than my 3T Team or Zero 100.

[Mario Jr.]

Hm, I have not tried any of those two. I had a Syntace F119 on my bike before and I can't feel any stiffness difference from that, if that's any help?

[tsutaoka]

my s3x is in the mail. after install i can compare it to my existing oval concepts r700

[mythical]

That Rotor S3X stem looks more like a Ritchey stem up front. Why did they move away from their patented DTT bar clamp construction if the system is supposed to be so good?

I do find it better looking than all its predecessors. Let's hope it works better as well!

[Wingnut]

The one bolt distributes the clamping force better, too.

How the hell do you come up with that result?

I would be more inclined to think clamping force would be more concentrated with a single bolt where as two bolts would distribute clamping force to a broader area.

[Mario Jr.]

That Rotor S3X stem looks more like a Ritchey stem up front. Why did they move away from their patented DTT bar clamp construction if the system is supposed to be so good?

I do find it better looking than all its predecessors. Let's hope it works better as well!

Because the DTT bolts on the faceplate made it quite difficult to install correctly for customers. The bolts had to be installed absolutely parallel and tightened only a little bit at the time. And if the customer unscrewed the bolts too much, the faceplate could be very hard to install. So the reason is because of the risk of user error.

The one bolt on the stem is partly same story. But you shouldn't worry about clamping force. All tests and pratical use shows that it's as safe as any two bolt system.

[tsutaoka]

my s3x is in the mail. after install i can compare it to my existing oval concepts r700

i got my rotor s3x today the 70mm stem weighed in at 90gms...that's 22gms less than the oval r700 at 50mm it replaced. in my initial 50mile ride with the stem, there were no difference in stiffness than the oval it replaced...that in my opinion is a good thing.

edit: here's a link to the photo http://picasaweb.google.com/lh/photo/BD ... directlink

[gitsome]

I've been running a ROTOR SX stem on my mtb for a while now and its great, light, good-looking, solid and holds firm. Admittedly it was a bit of a pain to install correctly and I am reluctant to fiddle with it now, but I am really happy with both its performance (including stiffness and weight) and looks.