The Zipp Service Course stem is a threadless road stem designed for use with 1 1/8" fork steerers and modern 31.8 mm handlebars. It is constructed from AL6061 aluminum to provide a consistent balance of strength, stiffness, and weight.
This version uses updated faceplate and body geometry to improve clamping stiffness and simplify installation. A four-bolt faceplate distributes load evenly across the handlebar interface. The ±6° angle provides standard road fit adjustment while maintaining a conventional cockpit position.
With a 70 mm length and a 41 mm stack height, this stem is suited for shorter-reach road setups or fit corrections on modern frames.
Fit & Use Signals
Fits 1 1/8" threadless steerer tubes
Accepts 31.8 mm handlebar clamp diameter
70 mm stem length
±6° angle for standard road fit adjustment
41 mm stack height
Intended for road bike cockpits using oversize handlebars
Not compatible with 26.0 mm or 25.4 mm handlebars
Requires proper torque on faceplate and steerer clamp bolts during installation