Rotor has updated its ultralight SL mountain bike stem with a stiffer shape plus a new steerer tube clamp design borrowed from its 3D crank.
The extension has been changed from a straight cylinder to a heavily milled-out conical cross-section for better torsional rigidity, similar to what the company has already done with its impressive S1 and S1X stems. Though this has added a few grams, total claimed weight remains a feathery 91g for a 90mm length (and still just 102g for a 120mm).
Rotor carries over the existing version's two-bolt removable face plate but the steerer clamp is now a single-fastener setup with a much larger bolt than before. New clamping supposedly still yields more evenly distributed clamp pressure on the steerer, though, and the threads are replaceable in the event of overtightening.
All bolts also use Rotor's slick dual thread pitch DTT Evo bolts with Torx heads.
The SL2 stem will be available in 90, 105 and 120mm lengths, all with a reversible 6-degree angle and traditional 25.4mm mountain bike bar clamp diameter only. Rotor says a 31.8mm version will be unveiled at Sea Otter and other stems will also soon be updated with the new single-bolt steerer clamp.