Innovation Lab: Long, Low, Slack

Mountain bikes look very different from when we first launched the Backcountry Series. Suspension is longer, frames are more slack and packs increasingly need to fill smaller spaces and accommodate moving parts. In the age of Long, Low, Slack, how do you design packs for technical riding?

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When we launched the Backcountry Series, our goal was to allow riders the freedom to choose the most appropriate bike for the terrain they would be riding, without having to worry about attachment points and hardware. In the years since, mountain bikes have become increasingly specialised and capable of tackling rougher terrain – improvements that have largely come through longer, lower, slacker geometry and longer-travel suspension. The flip side of these improvements is that it’s now more challenging to attach packs to modern mountain bikes and packs have to accommodate more shapes and geometries.

We pride ourselves on being problem solvers and one of the challenges our community of friends, ambassadors and riders kept flagging to us was the difficulty of fitting a saddle pack whilst also using a dropper post. Dropper posts allow riders to get lower and have more control over technical terrain, but they either drop the seat pack onto the rear tire or the attachment strap becomes caught in the dropper mechanism.

A table with a laptop, a tape measure, a scissor, a cup of coffee and two pencils on it

The Innovation Lab is where we push the boundaries of design, construction, and ideas to solve these problems. It’s a culmination of all the technical and experiential knowledge that we’re able to call upon when designing packs, and a vehicle to put this knowledge into practice. It’s where we do limited runs to test new ideas and prove theories, making it the perfect place to explore a saddle pack designed specifically for dropper posts.

Dropper Saddle Pack on a Mountain bike

The Dropper Puzzle

We’ve designed smaller saddle packs before, but simply shrinking existing packs wouldn’t fully solve the dropper puzzle. Dropper posts present a much more complicated challenge; not only does the pack have to avoid damaging or being damaged by the dropper post mechanism, but dropper posts are prevalent on dual suspension mountain bikes, where the distance between the saddle and rear tire is variable before you’ve even added the dropper post into the mix.

Solving the puzzle would mean rethinking the way we attach our packs and accepting that tire contact was likely.

Our community of riders told us that fitting saddle packs to bikes with dropper posts and suspension was challenging and limiting their choice of bike for longer rides, so we wanted to create a pack that addressed the challenge head on and gave riders a simple solution. The Dropper Saddle Pack showcases how we can take the popular and proven Backcountry Series and adapt it to even more technical styles of riding and bike designs with limited space.

-Olivia Cowley / Product Development

Problem Solvers

Unsurprisingly, the starting point was our Backcountry Saddle Pack, with tried and tested features such as our three-strap stability system, durable fabrics and reinforced contact points. The first priority was to modify the shape to maximise the space available, while decreasing the likelihood of tire contact.

Changing the shape of the pack meant changing the width of the attachment straps, which then needed to be tested for stability and tweaks made to their placement. A narrower strap would mean less interference with dropper posts, but it still needs to be wide enough to create a secure attachment point.

Next came reinforcing the pack against the increased chance of damage. While our Backcountry packs are all highly abrasion resistant, they are not designed to come into contact with the rear tire. Anything we added to protect the pack needed to be even harder wearing and able to take a lot of abuse. Rather than bulk up the fabric, the design team settled upon a removable HDPE skid plate. HDPE is hard wearing, but also works well with the materials we use on our packs, so with careful design, it doesn’t cause friction points that can damage the pack – often seen where hard and soft components combine.

Dropper Post Adapter

The biggest challenge, however, was working out how to maintain normal dropper post function, whilst preventing damage to the straps or dropper stanchion. The solution needed to be extremely secure, hardwearing and easy to fit and remove.

The solution came when talking to 76 Projects. 3D printing would allow us to create a very specific shape – curved at the front, but flat at the rear to enhance stability, while remaining low profile. 76 Projects specialist in 3D printing and component pieces, but more importantly they specialise in bikes, so understand the need for durability and performance – making them a natural choice for a partner. With their help, we were able to create a component that is highly functional and durable, but can also fit the vast majority of dropper posts on the market, through a choice of two included shims.

Apidura Dropper Saddle Pack Feature Image Cluster

Through extensive testing, we developed a component that uses wing nuts to allow the component to compress around the seat post, but only needs one side undone to attach and remove. This also gave us the freedom to make the backplate the optimum width for maximum pack stability. The design also relies on a choice of two different thickness of internal shim to allow it to fit a variety of dropper posts, rather than relying on multiple components. Finally, through testing we identified that the narrow attachment strap meant we needed a bigger lip on the component to avoid any slipping.

The Innovation Lab Dropper Saddle Pack signals our intention to embrace technical riding for Backcountry and the lessons we learned prototyping, testing and launching it will inform our approach for future packs for long, low and slack bikes.