Test: Who needs a 30mm wide race tire? Well, all those who sometimes want to ride something other than just smooth asphalt roads. But how does a slick tire fare on gravel? Velomotion tried the WTB Exposure 30c.
As the name suggests, Wilderness Trail Bikes comes from off-road sports. Located in California's Marin County, the cradle of mountain biking, the company specializes in saddles, rims and tires; In the course of the cross and gravel boom, the Americans have been putting out more and more 28-inch tires, down to the 23 mm narrow "ThickSlick". Of course, the focus is on wider tires that cater to a wider range of uses, and the Exposure 30c is one of the particularly interesting models for road riders. In trendy and beautiful caramel brown, this is a thoroughbred racing tire that only goes in the direction of gravel in terms of volume and is therefore perfect for current racing machines that can tolerate tires wider than 28 without offering the extreme throughput of a crosser. In the absence of the former, we mounted the WTB on the latter, but the objective is of course the same: to be fast on asphalt without being completely slowed down by bad tracks or dirt roads.
This is hardly possible with a narrow tire, because you have to make a decision when it comes to air pressure: if it is too high, there will be a lack of off-road comfort and traction; if it is too low, the rolling resistance suffers on asphalt, and the tire becomes spongy when leaning. The 30 mm tire, however, offers a wide range of air pressure: If you want to go off-road, you can officially go down to 4 bar (and in practice a good bit further), if you only drive on slippery roads, you can just over 6 fill in cash. Of course, the former applies with the restriction that you ride tubeless - otherwise low pressure could increase the risk of bottoming out.
The WTB Exposure 30c starts with a tour over smooth gravel roads and forest paths. It starts with a good 3 bar, and the slick tire already shows its road potential on the introductory two asphalt kilometers: Even with this rather low pressure, it feels light and very smooth, and it absorbs damage in the asphalt better than a narrower one Tires. This characteristic comes into play after a few minutes on an ascending gravel road in the forest: unless you hit the roughest chunks, the ride over the rutted path is surprisingly smooth; Traction problems when stepping out of the saddle are not to be found. The WTB Exposure can therefore convince on a brisk gravel tour without demanding cyclocross trails.
The tire has to prove itself on the road a few days later with significantly higher pressure. With more than 5 bar, the tire can hardly be dented, so it has to do less flexing work - and rolls even faster. The dual-compound mix with softer tire shoulders is said to improve cornering grip, which works very well. Whether the structure of the tire shoulders, which can hardly be seen with the naked eye, has an effect on grip cannot be said; in any case, there is never any uncertainty, even in fast corners with a lot of leaning. It should be noted, however, that the wheel with such wide tires has to be "bent" a little more - and the WTB is even wider than stated, namely almost 32 mm. It is also noticeable that the running direction is indicated on the sidewall - actually unnecessary with a slick, right?
The WTB Exposure is also comfortable at 5 bar - especially on longer distances you feel the advantages of good vibration damping, for example when your hands don't go to sleep anymore. The agility and handiness of the test crosser remained unchanged, which is not least due to the low weight of the wide tire: It weighs exactly as much as specified by the manufacturer, namely 310 grams.
The only problem is the tubeless assembly. The WTB snaps into place under the rim flange with a loud bang, but then it hisses and whistles everywhere. What's going on? Perhaps it is due to the coarse chafer that is located exactly where the tire is pressed against the rim: it is quite possible that air can escape through its mesh. We only got the problem under control with "Stan's Race Sealant", which WTB sales partner Sport Import kindly sent along. With its extra-large crystals, this curd is considered the most effective sealant on the market, which it impressively demonstrated at the WTB. In the meantime, the tire does not lose any more air than other tubeless tires during longer periods of rest.
In the end, the impression of a smooth-running, comfortable and non-slip racing tire remains, which is perfectly accommodated on disc racers with ample throughput. The WTB Exposure 30c should significantly expand their range of use without having a negative effect on the driving characteristics, as would an even wider, significantly heavier tire. So if you want to mix asphalt with forest roads and dirt roads without actually aiming for gravel tours, you could be very happy with the WTB.
