The Zipp SL-70 Aero[paid link] handlebars are among the most advanced road bike bars available today, designed for aerodynamic efficiency, stiffness, and ergonomic comfort. Replacing or adjusting them correctly ensures optimal control, performance, and rider comfort. This guide explains how to properly remove, install, and fine-tune your SL-70 Aero handlebars for a precise and safe fit.
Tools Required
- 4mm and 5mm hex keys
- Torque wrench[paid link] (with Nm scale)
- Carbon assembly paste
- Isopropyl alcohol and clean microfiber cloth
- Measuring tape or ruler
- Bike stand[paid link] (recommended for stability)
Understanding the Zipp SL-70 Aero Design
The Zipp SL-70 Aero handlebars feature a flattened aerodynamic top section designed to reduce drag and improve airflow. Constructed from unidirectional carbon fiber, they balance stiffness with vibration damping. The bar’s 70mm reach and 128mm drop offer a compact geometry, enabling comfortable hand transitions.
Its integrated internal cable routing supports both mechanical and electronic drivetrains, allowing for a sleek cockpit setup. This design requires careful routing during replacement or adjustment to maintain function and aesthetics.
Removing Your Existing Handlebars
Before installing the SL-70 Aero bars, safely remove the existing handlebars without damaging cables or the stem interface.
- Position the bike securely in a stand to avoid movement.
- Remove bar tape carefully from the tops and drops to expose the clamp area and controls.
- Disconnect shifters and brake levers, taking note of their previous positioning.
- Loosen the stem faceplate bolts evenly using a 4mm or 5mm hex key[paid link]. Do not remove one side completely before the other—alternate between bolts to avoid clamping stress.
- Remove the old handlebar gently, ensuring you don’t damage the headset cables or stem.
Clean the stem’s clamp area thoroughly with isopropyl alcohol before proceeding with installation.
Installing the Zipp SL-70 Aero Handlebars
Installation requires attention to detail, particularly with torque settings and alignment. Improper clamping can damage the carbon structure or cause creaking during rides.
Begin by applying a small amount of carbon assembly paste to the stem clamp area. This paste increases grip and reduces the required clamping force, protecting the carbon surface.
Next, align the center of the handlebars with the stem’s central line marker. Zipp includes printed alignment guides on the bar for accuracy.
Evenly tighten the stem faceplate bolts in a crisscross pattern to the torque specified by Zipp—typically 5.5 to 6.5 Nm (always verify with your stem manufacturer’s torque recommendation).
Ensure the bar angle suits your riding style: the flat aero top should sit parallel to the ground, and the drops should provide a natural wrist alignment when in the sprint position.
Adjusting Reach and Drop for Comfort
The SL-70 Aero’s geometry is designed for balanced control and aerodynamic posture. However, slight adjustments can significantly affect comfort and handling.
If you experience excessive reach, consider adjusting stem length or handlebar roll angle rather than forcing a forward posture. Small changes—1–2 degrees of rotation—can improve ergonomics without compromising aerodynamics.
The 70mm reach allows riders to maintain a compact position, while the 128mm drop provides an accessible low posture. Use a measuring tape to ensure symmetry between both sides, keeping your controls evenly spaced for consistent braking and shifting feel.
Cable Routing and Integration
The SL-70 Aero supports both mechanical and electronic cable routing, with designated internal channels along the top and drops.
For mechanical setups, route cables carefully to prevent sharp bends that can cause friction or premature housing wear. When using electronic systems such as Shimano Di2 or SRAM eTap AXS, follow the manufacturer’s cable and wire path recommendations to avoid internal interference.
Ensure that the cables enter the ports cleanly and exit without kinks. Any resistance or misalignment can affect shifting precision and braking performance.
Fine-Tuning Lever Position
Once the handlebar is installed and centered, adjust the brake and shift levers. For most riders, the lever tips should align horizontally with the bottom of the bar drops, allowing natural wrist extension during sprints and climbs.
Slightly rotating the levers inward by 2–3 degrees can improve ergonomics, especially for riders with smaller hands. Always check both sides for symmetry before tightening the clamp bolts to the recommended 6–8 Nm.
Testing Your Setup
Before wrapping bar tape, verify the handlebar alignment and lever reach by sitting on the bike and assuming your normal riding posture.
Confirm that:
- The tops feel flat and level.
- The drops offer a smooth wrist angle.
- There is no cable interference during full steering rotation.
If necessary, make micro-adjustments before final torque tightening. Once satisfied, rewrap the bars with your preferred tape, ensuring even tension throughout.
Maintenance and Long-Term Care
Regular maintenance ensures your Zipp SL-70 Aero bars maintain structural integrity and performance. Every few months, check the following:
- Bolt torque: Confirm all stem and lever bolts are within manufacturer specifications.
- Surface inspection: Look for cracks or delamination, especially near clamp areas.
- Cable condition: Replace any frayed or kinked housing to prevent friction.
Clean the handlebars with mild soap and water, avoiding solvents or abrasive cleaners that could damage the carbon finish.
Common Adjustment Mistakes to Avoid
- Over-tightening bolts: Exceeding torque limits can crush carbon fiber layers. Always use a calibrated torque wrench[paid link].
- Incorrect angle setup: A bar rotated too high or low can create wrist strain and aerodynamic drag.
- Neglecting paste application: Carbon paste is essential for proper grip and safety.
- Asymmetric control setup: Misaligned levers can cause uneven handling and discomfort.
Avoiding these mistakes ensures both comfort and long-term reliability of your Zipp SL-70 Aero handlebars.
Troubleshooting Fit Issues
If discomfort persists after adjustment, evaluate saddle setback and stem length before changing handlebar angle again. Handlebar discomfort often results from overall cockpit imbalance rather than the bar itself.
For ongoing wrist pain or numbness, consider changing the reach by stem adjustment or using thicker bar tape for added cushioning.
Conclusion
Replacing or adjusting your Zipp SL-70 Aero handlebars requires precision and patience, but the result is a more efficient, aerodynamic, and comfortable riding experience. Correct installation not only improves handling but also ensures long-term reliability of this high-performance carbon component. Regular inspection, correct torque, and periodic adjustment will keep your cockpit perfectly tuned for every ride.