SpeedPack

Yes, due to the smaller profile of the SpeedPack and the adjustability of the seatpost connectors, this bag should fit any bike.

No, the SpeedPack has a different mounting connector kit. You can buy the SpeedPack Top Bag + connector kit here, which will fit your current Rack or CargoPack setup.

Vs the CargoPack, the SpeedPack will fit best on full suspension/bikes with dropper posts. This is not to say the CargoPack won’t fit, but you may be compromised on space and range of movement under/behind the saddle.

Yes, the SpeedPack is compatible with both the Adjustable Light mount and Fixed light mounts. To fit the adjustable version, it must be mounted facing the reverse direction. Remove the base, rotate it 180º, and re-mount it facing towards the rear of the bag.

The SpeedPack will be available as a removable version from January 2026. Sign-up to our mailing list to receive updates.

The main compartment is 100% waterproof.

The front connector hardware has a 4-point attachment plate to the carbon internal frame. It comes with 3 different lengths of FitLink connectors 30, 60 and 90mm in length which are all adjustable up to +/- 50º of vertical alignment. The hardware at the rear is similar to the original, just 10mm lower and a slightly different profile, giving improved stability.

The wrap-around 3L mesh pocket of the SpeedPack is for items that you may want to be readily accessible or that are not impacted by the weather. For example, the mesh pocket could be used to keep a rain jacket or some extra food. It comes with a drawstring cinch to ensure the opening of the pocket can be cinched tight to ensure items are not lost.

Yes, from 2026 all spares are available on the Spares Page.

Yes, it weights 350g (bag only) and 700g when mounted on a Carbon Arch without pannier mounts. It is ~40% lighter than the current CargoPack.

The maximum weight limit you can carry in the SpeedPack is 8kg (road) and 4kg (off-road).

Yes, if you already have pannier mounts on your arch, you can use them with the SpeedPack mounted.

The SpeedPack’s internal frame is made of carbon to ensure lightness without compromising strength.

Assembly requires a Torx T25 key (found on most multi-tools), and you can find guidance on our Assembly guides.

We’ve designed our products to fit the majority of bikes, from road to full-suspension. You can search our Reviews to see if another customer with the same bike is already using this product too. We offer frame mounting as well as Axle mounting (both QR and Thru Axles). We have a useful guide explaining our mounting options. If you’re still unsure, contact our team for help and advice.

26″ Maximum Tyre Width – 4″ / 100mm
27.5″/650B Maximum Tyre Width – 3.5″ / 90mm
29″/700C Maximum Tyre Width – 2.9″ / 75mm

For help choosing your axle, please use our Axle Finder tool.

For riders with XS-L bikes or less than 100mm of exposed seatpost, we recommend selecting this in the configuration to choose the Long TopStay. For additional tips, see this blog post.

The fixed CargoPack System (V2 – Jan 2026+ only) comes with the long 50mm Seatpost connector as standard. This is not adjustable but is designed to fit as many bikes as possible. The V1 (pre 2026) comes with 2 lengths of seatpost connector, and the Extended Seat Post Connector is available on our Spares Page, too.

The fixed SpeedPack comes with 3 different lengths of FitLink connectors, 30, 60 and 90mm in length, which are all adjustable up to +/- 50º of vertical alignment. The hardware at the rear is similar to the original, just 10mm lower and with a slightly different profile, giving improved stability.

The arches on all our Rear Systems measure 447mm in height (when measured from the Thru Axle), so you can use this measurement to see how high it will come relative to your frame. We have many customers using our Rack system with XL+ bikes. In the configuration of your Rack order, you’ll need to select bike size (XL+) to receive the Short TopStay that we recommend for XL+ size bikes.

The fixed CargoPack System (V2 – Jan 2026+ only) comes with the long 50mm Seatpost connector as standard. This is not adjustable but is designed to fit as many bikes as possible. The V1 (pre 2026) comes with 2 lengths of seatpost connector, and the Extended Seat Post Connector is available on our Spares Page.

The fixed SpeedPack comes with 3 different lengths of FitLink connectors, 30, 60 and 90mm in length, which are all adjustable up to +/- 50º of vertical alignment. The hardware at the rear is similar to the original, just 10mm lower and with a slightly different profile, giving improved stability.

We don’t recommend using the Rack system with a full-suspension bike – it is best suited to road/gravel frames on road/light gravel riding. We recommend the fixed CargoPack and SpeedPack system for all terrains and on full-suspension MTBs. All our Rear Systems use a unique articulated design; each pivot contains replaceable plain bushings, which allow it to adjust position as the suspension compresses. See our blog for further tips on fitting Tailfin products to full suspension bikes. All our Rear Systems are compatible with road and gravel bike suspension systems such as Trek’s IsoSpeed and Cannondale’s Kingpin Suspension.

Yes, the quick-release seatpost connector is compatible with all seat posts, including dropper, carbon, and aero. An extra-long seat post strap is included with all shipments for deep-aero seat posts.

All our Rear Systems come with 2 choices for mounting:
– Axle + Fast Release Dropouts: Your system includes a rear axle (choice of QR or Thru Axles) to swap out on your bike, the Rack then fits to this axle in seconds, allowing it to be mounted or removed in seconds.
– Frame Mounts + Fast-Release Dropouts: Your system includes mounts which screw into the frame eyelets on your frame, the rack then affixes to this mount in seconds, allowing it to be mounted or removed in seconds.

We have a comprehensive mounting guide for the different options.

Yes, all Tailfin Rear Systems come with security torx screws that allow you to ‘lock’ your Fast-Release Dropouts to your Tailfin Axle, or Frame Mount Adaptors, depending on your chosen mounting option.

Yes, you will need to add our Third Party Pannier Adaptors to your order.