TOPEAK MTX Trunk Bag EXP 2.0 rear pannier-compatible bike trunk bag with expandable sides

The TOPEAK MTX Trunk Bag EXP 2.0 rear pannier-compatible bike trunk bag with expandable sides is a rack-mounted storage solution designed for bicycles with MTX-compatible rear racks. Constructed to provide organized, weather-resistant storage, the trunk bag offers a central main compartment and side panels that expand to increase capacity when needed. The design allows secure attachment to the rear rack while maintaining easy access to tools, clothing and daily items during commuting, touring or short errands.

Advantages

The expandable side panels increase cargo volume without requiring a separate pannier, and the trunk-mounted layout keeps weight centered over the rear axle for stable handling. Durable exterior materials and reinforced seams improve resistance to wear and light moisture. Integrated pockets and internal dividers help keep small tools and accessories organized, while a zipper closure and quick-release mounting ensure fast attachment and removal from MTX-compatible racks.

Suitable for

• Commuting and everyday city rides
• Short touring or overnight trips requiring compact luggage
• Grocery shopping and errand runs
• Transporting tools, spare clothing and small gear

Key specifications

• Mount type: Rack-mounted for MTX-compatible rear racks
• Expandable side panels to increase carrying capacity
• Main compartment with internal organizers and pockets
• Durable outer fabric with reinforced stitching
• Zipper closure for secure access
• Quick-release mounting mechanism for easy attachment/removal

How to use

Attach the trunk bag to an MTX-compatible rear rack using the quick-release mounting interface, ensuring the bag is centered and secured. Use the zipper to access the main compartment and organize items with the internal dividers and pockets. When extra capacity is required, open the expandable side panels and secure their closures to increase volume. Remove the bag quickly by releasing the mounting mechanism when taking it off the rack for transport or storage.

Recommendations

For best performance, distribute weight evenly and avoid overloading beyond the rack and bag capacity. Keep fragile items protected inside padded compartments and use internal organizers to prevent shifting. Regularly check mounting hardware and zippers for wear, and clean the exterior fabric according to manufacturer care instructions to maintain durability.

TOPEAK MTX Trunk Bag EXP 2.0 — a practical trunk-mounted option for riders who need modular, expandable rear storage compatible with MTX racks.