Road 31.8 OS
BLK/BLK or BLK/RED
90-130mm, 99g (90mm)
$202.00 Shipped

Tested in the 2007 Tour de France by Team Astana, the key to the S1 Stem is the exclusive use of Rotor's patented DTT design (Double Thread Technology); a double threaded design which eliminates the need for a head on the bolts. Each end of the bolt has a different thread pitch allowing for numerous technological advances not found on any other stem.

The key to the S1 Stem is the exclusive use of Rotor's patented DTT design (Double Thread Technology); a double threaded design which eliminates the need for a head on the bolts. Each end of the bolt has a different thread pitch allowing for numerous technological advances not found on any other stem.

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In a conventional bold design, the head fulfills two different purposes on a stem: (1) it pushes against the face of the stem (creating stress) and (2) it provides a surface to tighten the face against (also causing stress to the face of the stem); because of the added stress created by the head of the bolt, excess material is added to the stem and the face of the stem in order to provide a sturdy and reliable stem.

In Rotor's DTT bolts, the main threads engage onto the body of the stem and the secondary threads engage the face of the stem. When tightening, the different pitch threads evenly distribute the tightening load between the face and the body of the stem. The different pitch threads also allow for a lower tightening force while also producing a high torque value. This added torque value stiffens up the unit and the elimination of material helps minimize the weight and aids in the aesthetics of the stem design. The results: lighter weight, stronger clamping, better looks, increased reliability and a scant 99g total weight (90mm length).

The S1 stem has passed the most demanding European standard fatigue test (EFBe-Standard 7520), completed by the EFBe Institute in Germany, and the awarded "Top Performance" result for the single model offering, ensures that S1 is suited for both road and MTB riding alike. Road or MTB, the Rotor S1 stem will stand to the test of the most demanding riders.

FACT SHEET

• 90-130mm lengths for oversize handlebars (31.8mm clamp)
• +/- 7.5º rise
• 99g total weight (90mm length)
• Greater rigidity and strength: tightening load is distributed evenly between the head and body of the stem
• A 25% reduction in weight: by eliminating the heads on the bolts as well as excess surrounding material on the stem
• Blk/Blk and Blk/Red, stem/faceplate color patterns