Tech of the week: Van Rysel releases an aero bike (quelle surprise!) plus a superlight carbon crankset from FSA, a long top tube bag from Tailfin and tyre liners from Zefal

Aero race bikes are quite the thing these days. While some manufacturers have chosen to put their eggs in one basket, making an aerodynamically enhanced race bike that’s used across all races and stages by the sponsored professionals, some have opted to tread a more traditional route, making a dedicated machine for the flatter stages, that sits alongside something for when the road points upwards. Colnago just announced the release of its first aero bike in years, one that will be used by Pogacar and his UAE crew in the season ahead. And now we have Van Rysel following suit; its RCR-F aero bike will give the Decathlon AG2R La Mondiale team an additional option to the RCR, which it raced with a great deal of success last year.

One bike? More bikes? Who knows the answer but my feeling is great bike racers will win regardless. But it’s fun to see the differing approaches nonetheless.

Alongside the new Van Rysel machine we take a closer look at a lightweight carbon crankset, a simple device for reducing punctures and a voluminous top tube bag.

Van Rysel RCR-F

Van Rysel made headlines when it released the WorldTour’s most affordable bike, the RCR. The team, Decathlon AG2R La Mondiale, then played its part by racking up 30 victories for the 2024 season. So how do you look to continue that success in 2025? By releasing another bike for a start.

The RCR-F (fast?) is Van Rysel’s dedicated aero bike. It actually made its debut at this year’s Tour de France but gets a full release for the season ahead. Details are scant, with Van Rysel saying only that it’s a “powerful machine that will propel classic riders and sprinters to an unprecedented level,” as well as being “designed to slice through the air with speed”.

The upcoming Tour Down Under should see the RCR-F officially unveiled with a little more fanfare. However, it will be during the early Classics races and one-day events in Europe where it will really be put through its paces. Van Rysel are clearly happy it has created a bike fit for purpose. Now all the the Decathlon AG2R La Mondiale riders need to do is keep up their end of the bargain.

Zefal Z Liner

I’d hazard a guess that most cyclists fear winter riding not because of the cold and the wet - there are clothes and mudguards for that, after all - but rather the thought of getting a puncture. Changing a tube, roadside, with numb hands and a stream of uncaring motorists for an audience is grim stuff indeed. Which might just make Zefal’s new Z Liner the best stocking filler you'll receive this Christmas.

Offered in a range of widths for road, gravel and mtb tyres, it's a strip of protective tape made from what Zefal calls a 'highly resistant polyurethane material', designed to add a layer of additional protection. Sitting between the inner tube and tyre, it adds about 200 grams to each wheel. However, during winter, when a bibs and braces approach is advisable, it’s a small price to pay, should it work as advertised.

FSA SL-K Light crankset

As the name suggests, the FSA SL-K Light crankset is focused largely on weight, or lack thereof. It succeeds on the scales thanks in large part to the hollow UD carbon crank arms, which FSA says also offer ‘exceptional stiffness’.

Elsewhere the direct mount, cold-forged alloy chainrings use the brand’s Megatorq technology, a tooth profile design that aims to reduce dropped chains even when under extreme load, while ensuring smooth shifting at all times; FSA says this new tech has improved chain retention by 45% compared to the previous model. If you’re sceptical of numbers such as these, the SL-K Light crankset has not only been tested in the lab but also by FSA’s pro team partners, which include EF Education and Uno-X.

Available in four sizes - 50/34T, 52/36T, 53/39T, and 54/40T - they are compatible with all 12-speed Shimano and FSA drivechains, as well as a wide range of framesets, thanks, FSA says, to the innovative lockring on the left crank arm, which allows for minute adjustments.

Tailfin Long Top Tube Bag

I’m all in favour of products with self-explanatory names, such as the Tailfin Long Top Tube Bag.

Think of a typical bar bag you might use for bikepacking. Merge it with a ‘bento’ box that sits on the top tube and you get the picture. Tailfin says the Long Top Tube Bag “offers class-leading stability, significantly increased storage capacity, and clever organisational features.”

To achieve this it relies on the same V-mounts used on its other bags; this design negates the need for any stabilising straps. Then there are carbon stablising struts that aid the structural integrity of the bag, customisable organisation options thanks to the divider, and double entry zips, which are also waterproof.

It’s offered in three sizes - 1.6L, 2.2L, and 3.0L - with the first two suited to road and gravel frames, where knee rub can be an issue with some bags, while the largest volume bag is better suited to mtbs, thanks to their wider Q-factor.

The claimed weights are surprisingly light - 206g, 250g and 265g repsectively - given the measurement of the bags, which range between 370mm and 500mm in length, and the durable ripstop material.