I went into my first ride on these thinking that they looked an awful lot like a more rounded DHF, and lo and behold, that’s pretty much how they ride. While pointed in a straight line, I doubt I could distinguish between these and a DHF.
I’d say a DHF and the Goma roll at about the same speed (which is to say, definitely faster than a Maxxis DHRII, Schwalbe Hans Dampf, or Continental Trail King, and a smidge faster than a Maxxis Highroller II). They also offer similar traction for climbing and braking while upright.
Once leaned over, the differences are a bit more apparent. The more rounded profile of the Goma means that there’s a little bit longer period of driftiness before they hook up; you have to lean a little farther to really get the side knobs to fully engage. And even when they do engage, they’re not quite as locked in as a DHF.
The flip side of this is that the transition between center knobs and cornering knobs isn’t quite as well defined as a DHF, so the grip is a little bit more consistent as the tire is leaned over. To be clear, these differences are pretty dang minor, and there’s a good chance that experimentations with tire pressure and rim width would narrow the differences even further.
Vittoria doesn’t specify a durometer for the rubber compound in the Goma (aside from calling it “super grippy”), but I’d say it feels roughly like a 50a tire. It’s not as sticky and slow rolling as some of the really soft compounds, but it seems to hook up much better than a harder 60a tire. Similarly, they seem to be wearing about in line with what I’d expect from a 50a tire.
It’s worth noting that lots of companies use a dual-compound tread—usually a harder rubber compound in the middle to hold up better—and a softer compound on the sides to provide better grip. Vittoria has actually recently released some tires with four rubber compounds. That means that the “inside” of the center and side knobs each get a different rubber compound, and then those knobs are coated in two more different rubber compounds on the outside. The idea is to provide good support for the knobs, while at the same time allowing for a softer, grippier rubber. The Goma, unfortunately, doesn’t get that technology (yet), but check out the Morsa if that sounds interesting.
Given that the TNT casing on the Goma is pretty stout, I wouldn’t call them the most supple tires out there. They’re not as stiff as a DH-casing tire, but they didn’t conform to roots and rocks like, for example, the Continental Trail King. On the other hand, the Gomas didn’t fail on me almost immediately like the Trail Kings did.
Since I got these tires fairly late in the fall, I’ve only got about 10 rides on them. I’ll continue to ride them in the spring, so I should be able to get a better sense for wear and durability, but for the time being, everything looks good. I haven’t sliced any sidewalls, and the knobs aren’t showing any preliminary signs of failing. No news is good news.
In terms of the tread itself, if you like tires like the Minion DHF, the Specialized Butcher, or the Bontrager G4, I’m guessing you’ll get along with the Goma’s tread pattern just fine. It has a slightly more rounded profile than any of those tires, so if you want something that eases into a drift slightly less abruptly, the Goma might be the ticket.
And while the TNT version of the Goma is definitely at the heavy end of things, that extra material makes for a pretty stout tire. If you’re having trouble with sliced sidewalls or excessive flats on Maxxis Exo or Specialized Grid tires, but you don’t want to resort to a full on DH tire, the Goma in the TNT casing is certainly worth a look.