This review explores the Bontrager Adventure Top Tube Bag as a potential replacement for a traditional saddle bag, driven by the need for improved Garmin Varia radar placement. The author's initial setup, with the radar mounted on a saddle bag, proved inefficient and hampered the radar's functionality. Seeking a solution, the 1.6-liter Bontrager bag offered an intriguing alternative, especially considering the challenges of mounting the radar with a rear rack. The review details the author's experiment, transferring the contents of their saddle bag—including a spare tube, tools, and supplies—into the top tube bag to assess its practicality and capacity.The core question addressed is whether the Bontrager bag can effectively replace the saddle bag as a storage solution for essential cycling gear. The review examines the challenges of fitting various items into the relatively compact top tube bag, assessing the overall stability and security of the contents during a ride. Ultimately, it evaluates the trade-offs between space limitations and the aerodynamic advantages of a top tube bag over a traditional saddle bag, concluding with an assessment of its viability as a practical and convenient alternative for many cyclists.
Pros And Cons
- Fits a spare tube, energy tabs, multi-tool, tire levers, money, small tools, and a tire patch.
- Provides easy access to essential items.
- More aerodynamic than a saddlebag.
- Securely attaches with Velcro.
- Items need to be tightly packed.
- Slight movement of the bag when riding; leg might hit it.
- Bag is slightly tilted to one side.
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The Problem: Saddle Bag Limitations
Mounting my Garmin Varia radar to the back of my saddle presented challenges. With a rear rack, mounting was difficult. The biggest issue was using a saddle bag which forced the radar onto a small bracket, resulting in a downward-facing, inefficient position.

This poor radar placement significantly hampered its functionality, making it frustrating for safe cycling. That's why I sought an alternative solution.

Introducing the Bontrager Adventure Top Tube Bag
The Bontrager Adventure Top Tube Bag, with its 1.6-liter capacity, seemed like a potential solution. I purchased it at my local bike shop for around $39 MSRP.

I also considered the smaller Aerial Wedge, priced at about $24 with around a 1-liter capacity. However, I decided to test the Bontrager bag's ability to replace my saddle bag entirely.

Capacity Test: From Saddle Bag to Top Tube Bag
My saddle bag contained a surprising amount of items: a spare tube, energy bars, multi-tool, tire levers, money, small tools, and a tire patch.

The goal was to transfer everything from the saddle bag to the Bontrager top tube bag to assess its practicality and functionality as a replacement.

Fit and Function: A Tight Squeeze
Fitting everything into the top tube bag proved challenging. The long, narrow spare tube was the biggest obstacle, requiring me to carefully compact everything into the available space.

Despite the tight fit, I managed to get everything in and secure it with the Velcro closure. While some minor shifting occurred, the overall stability was surprisingly good.

Conclusion and Recommendation
The Bontrager Adventure Top Tube Bag proves to be a viable alternative to a saddle bag, offering easy access to essentials. Although it requires careful packing due to limited space, it functions well and secured the items effectively.

The streamlined design is more aerodynamic than the saddle bag. While minor stability issues exist with slight tilting, the overall benefits outweigh the drawbacks for many cyclists.
