A road bike tail bag in the shape of a capsule

External dimensions: 80×80×200 mm; weight (including hardware): approximately 300 g

Suitable for seatposts with a 44 mm center distance (most road bikes)

Approximate capacity: one spare tire (700×32C), basic tools (recommended to wrap in bubble wrap), 1.5 packs of tissues, and one AirTag (inside the rear cover)

The first ride test was completed at noon today—19.6 km with no issues...

• Unique capsule-shaped design
• Printing orientation and structural design prioritize stress distribution along the X and Y axes, with internal reinforcing ribs inside the body
• Removable display nameplates on both sides (included in the model; text can be customized via slicing software or by adding SVG, STL, etc.)
• Bottom section allows attachment of license plates, mudguards (included in the model), taillights, and more
• Mudguard features a foldable, two-piece design
• Adjustable angle for the seatpost bracket and adjustable length for the seat tube Velcro bracket (the red-ring nut shown in the image must be placed inside the bag)
• Angle-limiting teeth at screw connection points

• The rear cover uses a two-part, limited-rotation snap-lock mechanism (closed counterclockwise)

   

Non-3D-printed components required:

1. M5×16 screws, nuts, and washers—4 pieces total (3 mandatory)

2. 20×200 mm Velcro straps—2 pieces total (1 mandatory)

Assembly instructions:

1. Slip the central connecting ring over the bag body until it reaches the stop ring; if loose, apply glue. Allow a tolerance of 0.125 mm per side.

2. Secure the seatpost bracket and the central connector using M5 screws; inserting washers is recommended to enhance strength, and consider adding an additional Velcro strap to distribute stress evenly.

3. Attach the seat tube using Velcro; adjust the strap length so that the threaded end presses firmly against the seat tube (total length: 50 mm; if longer is needed, you can extend both the thread and inner/outer nuts simultaneously during slicing).