First Impressions | WTB Nano Race 40c Tires

With disc brakes and through-axles increasingly gaining favor on cyclocross bikes, the bikes are finding themselves more and more capable. With so-called ‘monstercross’ bikes being ridden on the same terrain that used to be the bread-and-butter of hardtail mountain bikes, drop bars are becoming much more at home on singletrack as they are on the ‘cross course. John Tomac would be proud.


Based off of the Nano tread pattern found on the 29-inch mountain bike tire WTB offers, the 700c version is tweaked slightly for longer durability.


True to their claims, the Nano measures out to an impressive 41.2 millimeters on a 23-millimeter IRW rim.

However, there’s only one problem with this—tire choices have been slow to follow, with many companies offering under-gunned tires that max out at just 32-35 millimeters wide. Not so with WTB though. With their newly released Nano 40c offering, the brand recognizes that many riders aren’t just looking for UCI-legal 33c and narrower tires.

Instead, the Nano sports a positively puffy casing that features a round profile that promises to offer plenty of cushion, while the centerline tread pattern with micro side knobs offers what should prove to be a great mix of grip and low rolling resistance. While marketed as a “gravel grinder” tire, we suspect the Nano 40c will see more than its share of fireroads and singletrack as well.

In ‘Race’ guise, the Nano features a foldable aramid bead, and a 60TPI version of WTB’s Race casing and is in turn sheathed in a single-durometer 60a rubber compound.

Having recently received our first shipment of Nano Race 40c’s, we were excited to mount up a set and see how they matched up to WTB’s claims. Stretching the calipers to a full 41.2 millimeters at the casing and 37-millimeters at the tread on a 23-millimeter internal-width rim, the Nano Race actually does measure up.

The same holds true on the scale as well, with our randomly-selected sample tire coming in 10 grams lower than the 470-gram weight claimed by WTB. Not too shabby at all.