Apidura Aero Top Tube Module
The Apidura Aero Top Tube Module is a strapped, aero-optimised top tube pack from a modular frame and top tube system that enhances aerodynamic performance for competitive gravel racers. It holds 0.4 L, weighs 100 g and attaches with two silicone-backed Hypalon load straps. Developed through Computational Fluid Dynamics (CFD) analysis, it smooths airflow behind the stem; combined with the Aero Frame Module it creates an average 5 watt saving at race speed, validated through wind tunnel testing.
Why an aero top tube module – and why this one
Air flowing over the stem leaves a low-pressure pocket behind it, which causes drag. A conventional top tube bag does not address this. The Aero Top Tube Module addresses it:
- It reduces drag. Transfer Panels bridge the gap between the stem and the top tube, so oncoming air glides across the front of the bike instead of getting trapped. With the Aero Frame Module, Apidura reports an average 5 watt saving at race speed.
- It integrates with the stem. The Transfer Panels are designed to conform to the stem for aero-optimised integration.
- It needs no top tube bolts. Two Hypalon load straps, backed with silicone to increase grip and featuring a cam lock system for added security, attach it to the top tube.
- It is quick to use. The magnetic opening allows quick, one-handed access, and a soft interior base protects the contents.
- Your knees keep their space. The slim profile reduces the chance of knee rub when sprinting.
Who is it for?
- Competitive gravel racers who want to improve aerodynamic efficiency.
- Riders whose bikes have no top tube mounting points – for bikes with top tube mounts, Apidura offers the Aero Bolt-On Top Tube Module.
- Riders building a full aero setup by combining it with the Aero Frame Module (Aero System S/M 305 g, L/XL 335 g in total, including the Frame Module).
The module is optimised for modern, flat-surface carbon top tubes and is also compatible with traditional round tube shapes.
Key features
Stem integration
Transfer Panels designed to conform to the stem for aero-optimised integration.
Quick entry
Magnetic opening allows for quick, one-handed access.
One system, your setup
Three top tube modules and two frame modules to mix and match.
Made from Hexagrid
Ultralight, high-strength nylon grid, laminated with TPU for a minimalist, yet structured material.
Hypalon load straps
Backed with silicone to increase grip and featuring a cam lock system for added security.
Knee clearance
Slim profile reduces the chance of knee rub when sprinting.
Materials & technology
- Hexagrid – an ultralight, high-strength nylon grid laminated with TPU to create a minimalist yet structured material. PFA- and PFC-free.
- HDPE – high-strength, rigid reinforcement boarding with good shape recall to avoid deformation.
- Aero optimised – active improvement of the aerodynamic performance of the bike and rider.
- Ultralight – minimal design and lightweight materials for optimal weight-performance.
- Wind tunnel tested – the Aero System is validated through wind tunnel testing, with an average 5 watt saving when the top tube and frame modules are combined.
Specifications
| 0.4 L (TTS) | |
|---|---|
| Capacity | 0.4 L |
| Storage | Single main compartment |
| Closure | Fast entry magnetic closure |
| Attachment | Two Hypalon load straps, silicone backed to increase grip |
| Structure | Internal HDPE thermoplastic frame |
Care & maintenance
- Spot clean only – stains can be spot treated with concentrated dishwashing liquid. Abrasion is not recommended.
Frequently asked questions
How does the Aero Top Tube Module improve aerodynamics?
Air flowing over the stem creates a pocket of low-pressure air directly behind it, which causes drag. The module's Transfer Panels bridge the gap between the stem and the top tube, filling this space so oncoming air glides smoothly across the front of the bike instead of getting trapped. This reduces aerodynamic drag.
Can I use the Aero Top Tube Module with steel, titanium or other traditional round tube shapes?
Yes. The Aero Top Tube Modules are optimised for modern, flat-surface carbon top tubes but are compatible with traditional round tube shapes. The slim profile and non-slip silicone base ensure a stable fit; the strapped version uses secure, silicone-backed Hypalon load straps.
How do I attach the Aero Top Tube Module?
The module uses Hypalon load straps with silicone backing to attach securely to the top tube.
About Apidura
Founded in 2013, Apidura designs bikepacking bags for long-distance and ultra-endurance riding, tested by riders on events such as the Transcontinental Race and the Tour Divide. The range is built around three families: the fully waterproof Expedition series for touring and all-weather bikepacking, the lightweight Racing series for ultra-distance racing, and the rugged Backcountry series for off-road trails.
Every Apidura product comes with a 3-year producer guarantee from the date of purchase, covering the entire product. After that, Apidura can support at-home repair or recommend a trusted repairer.
