The C260 Carbon Matrix UD stem is the absolute pinnacle of Ritchey stem technology. The carbon matrix design is a great choice for the rider who doesn't mid a small (10 gram) weight penalty for a large (15%) increase in stiffness and a damper ride quality. Stunning gloss finish is stare-worthy and is a beautiful example of a well-made product.
The most noteworthy feature of the C260 stem is the clamp and faceplate design. This is where the stem's namesake is derived. The C260 nomenclature effectively means Circumference 260 degrees. If you take e peak at the sideways profile of the stem, you can see the clamping area that is on the stem wraps around the bar 260°, while the faceplate is a mere 100° to complete the 360° wrap of the handlebar. In effect, the stem clamp holds around 2/3 of the bar in an over-center design and the faceplate holds only about 1/3 of the bar. A stark difference from the 50/50 support of the standard faceplate design. This design produces a more balanced and circumferential clamping force on the bar instead of the more two-dimensional vise-like force of a standard faceplate design. The faceplate fixing bolts now clamp from the back and create a smooth svelte look.
At the rear of the stem, the clamping mechanism to the fork has been altered from previous designs as well. The slanted slot is replaced with an arcing radius and 3 bolts with the middle bolt having an opposed direction from the top and bottom bolts. This helps further reduce the amount of stress on the steerer tube of today's super lightweight carbon forks.
The C260 Carbon Matrix features matrix carbonalloy technology. This means the stem has a 3D net forged 2014 alloy core that is encased in high-modulus carbon fiber. Imagine taking a standard C260 stem that has been pared down to a super thin thickness then wrapping it in carbon fiber. You basically have a thin alloy core with a thicker carbon contain/layer enveloping it. Very clever design that works. It improves fatigue strength over the alloy version of this stem(not that that was ever a problem), but more importantly and relevant is the fact it makes the stem stiffer and provides better dampening from road vibration. Beyond improved ride quality, the stem is just gorgeous. The gloss coating resist wear and cleans up nice after workouts. All bolts are M3/M4 micro sized and coated black. Low-profile, but classy logos round out the package.
Ritchey C260 stems have been coming with T20 Torx bolts - not Allen (hex) bolts. Please verify and use the correct tool.