FSA OS-99 CSI Stem
Best lightweight upgrade for performance oriented road cyclists seeking stiffness.
This hybrid component blends the stiffness of forged aluminum with the vibration-damping properties of carbon fiber. It offers a lightweight, high-performance solution for riders looking to shave grams without sacrificing the structural integrity required for aggressive road riding.
$186.20
More K-Force options
Who it's for
- Performance cyclists seeking a balance of stiffness and comfort
- Weight-conscious riders looking to optimize their bike's front-end performance
- Enthusiasts who value professional-grade styling and a clean cockpit appearance
Who should skip it
- Budget-oriented cyclists looking for simple, cost-effective cockpit components
- Home mechanics without access to a precise torque wrench
- Endurance riders seeking a softer, more forgiving front-end feel
Performance breakdown
Stiffness-to-Weight Ratio
Hybrid carbon-aluminum construction provides exceptional rigidity without the typical weight penalty.
Vibration Damping
Carbon weave integration effectively mutes high-frequency road buzz for smoother handling.
Hardware Quality
Titanium bolts offer premium weight savings and superior corrosion resistance.
Installation Precision
CNC-machined tolerances ensure a secure, slip-free fit on standard steerers.
Clamping Security
Four-bolt faceplate distributes pressure evenly to protect lightweight carbon handlebars.
Aesthetic Integration
Sleek, sculpted profile complements modern race bike geometries perfectly.
Key Specs
Material
AL2014 Aluminum and Carbon Fiber
Weight
126g (100mm)
Stem Angle
6 degrees
Handlebar Clamp Diameter
31.8mm
Steerer Tube Diameter
1-1/8 inch and 1-1/4 inch
Stack Height
41mm
Bolt Material
Titanium
Number of Bolts
4
Know before you buy
Still have a question?
Ask Metto anything about the FSA OS-99 CSI Stem before you decide.