RSX Direct Mount Stem

The rise of the RSX stem represents the distance between the centre of the bar and the plane of the fork's direct mount interface.

Yes, you can install the RSX stem with either wider or narrower bar clamp spacing.

You need at least a 50mm straight section for the narrow bar clamp spacing setup and 90mm for the wider spacing setup.

The RSX stem uses M6 bolts with a 1.0mm thread pitch and a 20mm threaded section. Each bolt includes a 1mm washer at the bolt head.

A direct mount stem bolts onto the upper crown of a dual crown fork instead of clamping around a steerer tube, which is why the RSX has no steerer clamp and no stack height in the spec table. That makes it stiffer and lower, but it also means it only fits forks with a direct mount upper crown — it will not go on a single crown fork. Check your crown before ordering.

The RSX is a common upgrade on Sur Ron and Talaria builds. What decides it is the crown rather than the badge: the RSX bolts onto a direct mount upper crown instead of clamping a steerer tube, so if your triple clamp has the direct mount holes, it goes on. Look at your upper crown before ordering.

On a Sur Ron, take the 31.8mm clamp with 30mm of rise. Note that rise on a direct mount stem is measured differently from a normal stem — it is the distance from the centre of the bar down to the plane of the direct mount interface, so 30mm here is not the same thing as 30mm of bar rise. The 31.8mm RSX weighs 140g in 20mm rise and 160g in 30mm.