Same panniers mounted to a fatbike.

Waterproof panniers

Updated May 2022

Here’s a brief video outlining the third pair of waterproof DIY I’ve welded up from nylon TPU. Several thousand kilometres of successful bikepacking on the second pair have been incorporated into some minor design tweaks such as a compression weather cover for the roll-top closure and simplified single-strap attachment system. This pair of relatively high volume panniers (~15 litres each) came in at around 550 grams as I incorporated extra layers of TPU fabric at key wear and stress points, and added welded heavy duty D-rings to allow the straps to be easily replaced in the field without tools . I adopted a 20,000 km mindset in the design and construction of this pair of panniers, hence the slightly higher weight. Version 2 with similar volumes weigh about 375 grams for the pair and do not have a weather cover. It’s worth noting that V2 continue to perform well and have proven extremely tough and durable through some challenging backcountry trips.

The panniers are designed to secure near the rear axle level which lowers the centre of gravity relative to typical panniers. My MSR Hubba NX loads vertically and then sits almost entirely below deck of the DIY rear rack. Width of the entire system is less than 18″ on the fatbike and 17″ on the 29’er.

While this example is welded TPU the same design elements work very well with sewn DIY systems.

February 2020

February 2020 – This project was a result of a first attempt at learning how to thermally bond different types of TPU coated nylon. These two products were 115 GSM (3.4 oz) Heat-Sealable Ripstop Fabric: Yellow and 190 GSM (5.6 oz) Ripstop Fabric, TPU Both Sides . While they’ve not had the extensive testing of other ideas on this site, the first few hundred kilometres have been very positive. Finished weight is just under 400 grams for the pair with all mounting straps, and they’re likely overbuilt by about 10%. Each bag is 10 cm deep, 20 cm wide and 50 cm tall (open) and 40 cm (closed with 4 folds) for a nominal volume of about 8 litres each. Effective working volume is ~9 litres. The laminated fabric is still easily opened and closed in the -30’s C. This posting is intended to be a DIY thought-starter not a detailed description.

An overnighter with the new bags.

This was a very time consuming project. Largely due to laminating the two fabrics together. The bags have shown no wear from both singletrack riding and loading into trucks. The only sewing was to attach the Omnitape straps to panels which were then welded to the bags, and sewing the buckle closures on.

  1. Thanks for the review Steve! Much appreciated. Steve is riding with an mid-2019 prototype. While you can use a Voile…

  2. I picked up a set of these babies at the last Bikepack Canada Summit. What a great addition to the…

  3. I’ve used the FenderBag on a few trips now and I just love it. To be able to efficiently use…