off-road.cc

The Straight Cut Top Tube Bag is a large, easy to use and very sturdy design that can store loads. Good water resistance and multiple fixing options make it very versatile.

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Straight Cut produces just one size as standard, which is approximately 1.1 litres in volume. It is quite sizeable for a top tube bag, although they do also offer any number of custom options which could include custom sizing as an extra service.

The standard bag measures 220mm in length and 100mm in height. The bag sits reasonably wide, especially on a steel frame gravel bike, but it tapers from 80mm at the front to 50mm at the rear. Despite initial concerns I had no problems with knees rubbing, even when stood up out of the saddle.

The bag is available with a few different mounting options, including a direct mount (£70) should you have suitable fixings on the top tube. There standard Velcro straps we have on test can also be swapped for Voile Nano straps (£68). All these options are available with the front attachment point horizontal as is often standard, or vertical, which means it can fit onto a drj0n bagworks DeWidget as seen here (review of that soon).

Under the bag are five different top tube attachment points, which should ensure whatever bike you have this will fit around cable stops or anything else. The bag also has a large and easy to use cable entry port on the front section. It's tall enough inside to prevent any rain or spray entering.

The construction is faultless with very strong stitching throughout, excellent materials and a waterproof zip with garage area. Another nice touch is a glow-in-the-dark zip puller, which can make access a little easier on night rides. When empty, or near empty, the zip is still easy to open and close with one hand, as the bag holds its shape pretty well.

While the bag cannot be technically classified as waterproof, due to the cable port, the zip and the fabrics are waterproof and no water got in during our test – even when the bag was targeted with a hose pipe. Consider it extremely water resistant, then.

While £55 for a top tube bag is expensive, each one is hand made to a very high standard and a strong design – it's a fair price for what it is. At 96g it's not the lightest bag of this size, but that's the cost of its quality and strength.

The Alpkit Fuel Pod 25 is a similar size, around 20g lighter and £35, but lacks the same stability (it's not compatible with a DeWidget mount either), and we suffered fitment issues. For a smaller, much cheaper option, the Lifeline Adventure Top Tube Bag is just £15 and works well – given the price it's easy to overlook any niggles.

Overall the design, construction and performance of this bag are really excellent. The wide base could potentially be an issue to some riders who pedal with knees close to knocking, but otherwise it just works well. It's extremely weatherproof, a useful size and a pleasure to use. A lot of thought has gone into both its design and build, and it shows.

• straightcutdesign.com

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