Continental has announced a narrower, 50mm / 2in version of its Dubnital cross-country mountain bike tyre, designed for use on gravel bikes. Following the recent launch of Continentals Terra Competition, which uses a low-profile, all-road tread and is available only in sizes up to 45mm, the new 50mm Dubnital is intended to fill the hole in the brands range between its dedicated gravel and cross-country MTB tyres. As Continental notes in its press materials, the Dubnital and its predecessor, the Race King have gained popularity among gravel racers in recent years, as riders have searched for tyres that offer lower rolling resistance and better grip on rough trails than dedicated gravel tyres. However, with many gravel bikes not being capable of accommodating the Dubnitals smallest, 55mm / 2.2in option, there was growing demand for something larger than 45mm but smaller than 55mm. Rather than developing a dedicated gravel tyre in this size, as Schwalbe did with its G-One R Pro range, Continental has decided to simply size down its XC tyre. Read more: Simon says: don't buy a gravel bike without at least 50mm of tyre clearance you'll regret it Removing the boundaries between MTB and gravel XC mountain bike tyres have been a hot gravel trend in recent years and Continental is listening. Continental Continental makes no bones about the Dubnital being an XC tyre first and foremost, but with the demands of gravel racing evolving rapidly, the brand seems happy to give riders exactly what theyve been asking for, rather than developing something distinct. Alexander Haenke, Continentals MTB and gravel product manager, says: With the introduction of the Dubnital 50mm, we are removing the boundaries between mountain biking and gravel once and for all. In this 50mm dimension, it hits a distinct sweet spot for technically demanding offroad races such as Traka, The Rift or Badlands, Haenke says. Previously, the smallest available Dubnital was a 55mm / 2.2in option, but only a few gravel bikes can accommodate tyres that large. Simon von Bromley / Our Media The tread is aggressive compared to Continental's dedicated gravel tyres. Simon von Bromley / Our Media Like its larger siblings, the 50mm Dubnital therefore features a tread optimised primarily for off-road riding, rather than a mix of tarmac and gravel. Compared to Continentals Terra Competition or Terra Speed gravel tyres, then, the Dubnitals tread is much more pronounced. According to the brand, the tightly spaced knobs in the centre of the tread are designed for good rolling efficiency in a straight line, while slightly larger, more widely spaced shoulder knobs offer better traction for off-road cornering and braking. Continental says the 50mm Dubnital is the perfect choice for "technically demanding offroad races". Continental While this should naturally provide better performance off-road, it remains to be seen whether this approach proves slower on tarmac or lighter gravel than the previously mentioned alternatives. As always with tyres, tread patterns arent the sole deciding factor when it comes to rolling resistance casing construction and rubber compound also play significant roles. Two casing options and one compound There are two casing options, but only one compound for this new 50mm option. Simon von Bromley / Our Media As with the wider tyres, the new Dubnital 50mm is available with two casing options Race or Trail and costs 66.99 / $86.95 / 74.95. As the names suggest, the Race casing is designed for the lowest rolling resistance possible, while the Trail casing features increased puncture protection and greater stability at lower tyre pressures. Both casings use Continentals low-rolling-resistance Rapid rubber compound, are tubeless-ready and are compatible with hookless rims. There's some variation between tyres, as usual, but ~580g or so is decently light for a tyre such as this. Simon von Bromley / Our Media Schwalbe's Thunder Burt 2.1in tyres come in at a similar weight to the new 50mm Dubnitals. Simon von Bromley / Our Media Weve got the Race version in for testing, and our samples weighed 576 and 589g per tyre. Thats roughly in line with a set of 54mm / 2.1in Schwalbe Thunder Burt tyres (with Schwalbes SuperRace casing), which weighed 560 and 580g on our scales. Its also only20 to 35g more than a 45mm Continental Terra Speed, which tipped the scales at 555g with transparent sidewalls so theres less of a weight penalty than you might expect for the additional volume and tread.