32-inch gravel bike test: French frame builder Chiru is among the first manufacturers to venture into the new wheel size. Velomotion was able to borrow the Chiru Veldt for a test ride – here are the findings from riding the giant wheels.
When new technologies hit the market, we quickly begin to question what we already know. Bicycle inner tubes, mechanical shifting systems – those who are up-to-date with the latest technology sometimes wonder what simple materials they used to get by just fine. Will this soon apply to wheel size as well?
32 inches: Rolls better with larger wheels
With 32-inch wheels, the industry is opening a new chapter. The first MTB race victories on the larger wheels are being cited as proof of the new size's superiority, and rumors are circulating about even more riding fun. Those coming from road cycling might find this a bit surprising. After all, road cyclists have been using the same wheel size for decades, and somehow it's always worked well. Perhaps the problem is that the first mountain bikes were designed around small 26-inch wheels – these, along with suitable high-volume tires, were readily available, and until the first 29ers around the turn of the millennium, nobody considered that larger wheels might offer better rolling characteristics. Meanwhile, 29 inches (i.e., a 622 mm/28-inch rim with a high-volume tire) has become the standard for MTBs, and the trend towards wider tires has also spread to gravel bikes.
Now comes the next step, and purely from an aesthetic point of view, one might ask whether one wants to go along with it. The perfectly crafted, slim titanium frame of the Chiru Veldt The bike's massive wheels overshadow its appearance; the challenges that 32-inch wheels pose for frame geometry clearly deviate from conventional perceptions. And so one might ask whether all this justifies certain advantages in handling – and if so, which ones?
Dynamically rolling over obstacles
Simply put: larger wheels roll over obstacles more easily. The further the tire's contact patch is from where it touches the obstacle (e.g., a curb), the more distance the tire has to overcome the obstacle – and the less it is slowed down in the process. The longer wheelbase required by the larger wheels has another advantage: relative to this, the front wheel is lifted less. And this is where the truly noticeable advantage of the 32-inch wheel concept, in combination with the 57 mm wide tires fitted to the Chiru, comes into play.
How big is 32 inches exactly? The outer radius of a 28-inch rim is approximately 32 cm; when... "Bike Ahead Composites" wheelset The Chiru's axle-to-wheel drop is around 35,5 cm. On a conventional gravel bike with 40 mm tires, the axles are about 35 cm above the ground, while on the 32 mm model, it's just over 40 cm. Combined with the differences in frame geometry necessitated by the larger wheels – long chainstays and a longer front end, and a slacker head angle – this results in significant differences in handling. A slight wobble is noticeable on the first few meters on asphalt, but this is quickly mastered; the fact that the Chiru requires some effort to steer also takes some getting used to. Standing up to pedal isn't exactly the 32 mm model's forte: when you get out of the saddle, the bike is reluctant to move from side to side. Short, steep sections are better tackled with a high cadence while seated rather than pushing hard, and the SRAM Red derailleur plus the wide-range Garbaruk cassette prove their worth with lightning-fast gear changes.
It's better to start sitting down.
On an uphill gravel path with high, transverse drainage ditches, the major advantage of the large wheels becomes apparent for the first time: On a sporty cyclocross/gravel bike with 40mm tires, you have to lift the front and rear wheels significantly, which results in a noticeable loss of speed. The Chiru Veldt simply rolls over the ditches; if you ease off the handlebars slightly, the impact is barely noticeable. The vibrations from the uneven surface are also significantly dampened.
This characteristic results in solid straight-line stability at any speed, and the bike remains easy to control despite the narrow handlebars. Confident that the large, 57 mm wide tires efficiently absorb road shocks, you can simply let it roll downhill, whereas on a conventional gravel bike you would need to ride more actively and cautiously. When cornering at speed, you'll notice that the wide tires allow for greater lean angle – making twisty roads feel very dynamic.
A tire for drier roads
The wide Maxxis tires can be ridden with extremely low pressure and offer quite good grip, even for experienced riders. However, in muddy conditions, the large contact patch of the tires seems to cause some hydroplaning. A more pronounced tread pattern would certainly be better in these conditions.
The Chiru Veldt weighs just 9,2 kilograms, thanks in no small part to its extremely high-quality components: the [missing information] weighs only around 300 grams. Cockpit, about 1.500 The wheelset's gram of weight, from the comfortable Carbon saddle Not to mention the Franconian lightweight brand. However, the bike isn't exceptionally powerful. Ready to ride, the wheelset weighs a good 3,8 kilograms, with the tires shifting a significant portion of the mass to the outside. While this means the bike maintains its speed easily, depending on the tire pressure, you can definitely feel energy being lost due to tire deformation.
So how should we assess this new trend? The Chiru Veldt, with its flat bars, could also be conceived as a lightweight, rigid mountain bike that takes typical 29er tires to the next level. From a road bike/CX perspective, it's exotic, even extreme. There's definitely something to be learned from this concept – namely, the advantage a larger tire diameter offers in terms of riding dynamics. Anyone who previously considered 40 mm wide tires the gold standard might be tempted to try pushing the limits of their gravel bike's tire clearance. Whether one is willing to sacrifice the familiar handling of a conventional gravel bike is another question, and the market will decide once 32-inch bikes are available in larger numbers and at typical prices. It could be a success – or it could go the way of fat bikes…
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