Fuel tank top tube bags have been knocking about in triathlon circles for years. Designed to carry gels, bars and other useful bits and pieces it would be handy to reach while riding, they're incredibly useful for sportives and training rides, not just triathlons. The Topeak Fast Fuel Tri Bag might be one of the most expensive I've come across, but it outclasses most of the competition in terms of size, stability and build quality.
The build quality is obvious as soon as you take it out of the packaging. In my experience, many fuel tank bags can be flimsy and designed purely for low weight rather than long duration, usability and performance.
There are two popular designs – short in length but higher, or longer in length and contoured to slope down from the head tube. This Topeak follows the latter pattern and has a capacious stated volume of 0.6l, a genuinely roomy storage area.
The bag fastens to the head tube and top tube via three Velcro straps, the rear one having a rubberised underside to help grip the tube. The base of the bag is also slightly rubberised. For tri bikes with appropriate bottle bosses on the top tube, the bag can fasten directly to those.
A single zip at the top allows access to the storage compartment, and features a garage to tuck the zip pull into when closed, or a Velcro tag to stick it to if you want to keep it open.
Inside the bag, there's a small mesh pocket at the side and also a removable stiffened divider for those who like to micro-organise their space.
It certainly was very easy to fit to the bike, and the most impressive feature for me was that, despite its relatively large size by fuel tank standards, it didn't intrude on my riding at all, even when up out of the saddle. Past experiences with this sort of thing have usually resulted in me growling as I have to adjust my climbing style to avoid the bag. Partly instrumental in that is the bag's stability: it doesn't shift at all during rides, staying secure and non-floppy thanks largely to the rubberised base and strap, as well as the shape.
There was plenty of space for an iPhone 5, some money, gels, a couple of bars and even a packet of tissues, meaning for long events it's an ideal repository for in-ride essentials. The closure isn't waterproof, but a simple plastic bag would safeguard vulnerable electronics. I didn't feel the need for the optional divider and took it out to give more versatile space, but if you're more organised than I am you might want to leave it in.
All in all, despite the fact that it's one of the most expensive of its ilk that I've come across, it is genuinely spacious, well constructed, well designed and offers a really useful alternative to stuffing rear jersey pockets full of small bits and pieces and risking a soggy, sweaty phone.
Pricey, but worth it for a durable and versatile way of carrying phone, gels and snacks during events and long rides
road.cc test report
Make and model: Topeak Fast Fuel Tribag
Size tested: 24x8.5x5.5cm
Tell us what the product is for, and who it's aimed at. What do the manufacturers say about it? How does that compare to your own feelings about it?
Top bar mounted bag for gels, snacks and useful bits and bobs required during a ride.
"Stylish slim top tube mounted bag giving cyclists quick and easy access to energy bars, smartphone, wallet, tools or any small essential gear they need close at hand."
A nicely designed alternative to stuffing rear jersey pockets.
Tell us some more about the technical aspects of the product?
600 denier polyester TPU clear top cover
Adjustable nylon straps
Main padded compartment with dividers
Fits 38-52mm diameter top tubes, and 53-75mm diameter head tubes
145g stated (weighed by road.cc at 142g)
Very well made with some nice touches like the rubberised strap to help stabilise the fit to the tube. Sturdy fabrics and durable.
Did a great job, was roomy enough for all sorts and didn't interfere with pedalling action even when out of the saddle. Very secure too, with no wobbling about.
Seems extremely tough.
Not the lightest, but designed with durability and efficacy in mind.
Pricey, but you'd probably not have to buy another one for years and it's a genuinely well-designed bag in a useful size.
Tell us how the product performed overall when used for its designed purpose
Very well indeed.
Tell us what you particularly liked about the product
Style, volume, stability, lack of interference with pedalling, even on a small framed bike.
Tell us what you particularly disliked about the product
Did you enjoy using the product? Yes
Would you consider buying the product? Definitely
Would you recommend the product to a friend? Yes
Use this box to explain your score
Made from good quality materials and well shaped, it's very good, offering plenty of usable space for the things you need to be able to reach during a ride. It's expensive but it's durable and effective.
About the tester
I usually ride: Boardman Hybrid Fi My best bike is: Specialized Ruby Elite
I've been riding for: 10-20 years I ride: Most days I would class myself as: Experienced
I regularly do the following types of riding: commuting, touring, sportives, general fitness riding, mountain biking
Lara has been riding bikes for longer than she'd care to admit, and writing about them nearly as long. Since 2009 she has been working as part of the road.cc review team whilst championing women's cycling on the side, most notably via two years as editor of the, sadly now defunct, UK's first and only women's cycling mag, erm, Women's Cycling.
Believing fervently that cycling will save the world, she wishes that more people would just ride a bike and be pleasant to each other.
She will ride anything with two wheels, occasionally likes to go fast, definitely likes to go far and is always up for a bit of exploring somewhere new and exciting.