Rubena Scylla & Kratos 29″er Tires: Mid-Term- by Guitar Ted
Since my last post on these tires, (seen here), we have gone through the transition from wet to very dry here. This has allowed me to test the Scylla and Kratos over a wide variety of conditions since I last wrote about these two 29″er tires. Following are a few more impressions on these two tires I have to share with you….
Since the weather has dried up the trails, I have been liking the Scylla more and more. The hard pack conditions are well suited to this tire and that has confirmed my suspicions that the Scylla is indeed a specialists tire. The conditions made for fast speeds with great grip in corners, no doubt due to the dual compound tire construction here.
My feelings about the casing shape are mixed; however, since it does provide for decent speed. It also makes for a tire that can get “pinged” off-line due to trail obstacles. Something that was readily apparent from my trip to Texas which I reported on last time. This didn’t occur with such regularity up here in the Mid-West, but when it did, it was a bit disconcerting, with the bikes change in direction and the accompanying loud “pop”.
The very rounded profile does allow for great turn in though. Got a sluggish feeling 29″er? This tire might help your turn in feel a bit. The rounded profile also helps with speed, especially if you get into higher pressures. I found 35psi rear/ 30 psi front, (2.41Bar Rear/ 2.07Bar front), was optimal for a good balance of speed and grip on our hard packed dirt here. The casing on the Scylla seems to be stout, and the feel is average. Not too stiff or too supple.
The Kratos is becoming one of my favorite “all around” tires. In the last report I told you how I found the Kratos to grip in wettish, softer trail conditions well. Now that it has become dry, the grip is still there, but now the speeds have picked up as well. This is because the knobs on the Kratos are not piercing and pulling out of the trail surface, like they do when the trail is soft, but the knobs also do not appear to flex on hard pack either. I believe the Kratos casing is to be credited here.
The casing has a smooth ride feel with a nice bump absorbing quality. It truly feels much bigger than it is, (and that size is one of my gripes about the tire), but it rolls nicely and grips well due to that casing, I think. It just feels like this tire is working over the terrain more than the Scylla’s casing does.
While the casing profile is just as rounded as the Scylla casing, it doesn’t cut in and wash out in deeper grounds and sand like the Scylla. Here I would give a nod to the more open tread with bigger blocks. In sand, I found the Kratos would drift well, but never really wash out, which made sandy pits in the trail rideable and even almost fun.
Pressures were similar to what I have been trying with the Scylla, so again, a bit higher than I typically use for many tires I test. However; this seems to suit the Rubena tires better than lower pressures, so it is what it is.
Mid-Term Conclusions: The Rubena tires are both really good tubeless tires which will seal up and retain air quite nicely. Both get high marks for tubeless performance. In terms of wear, I only found the Scylla to wear more quickly in severe rocky terrain. The Scylla and Kratos seem otherwise “normal” for wear on my local trails.
I do find the overall sizing on each tire to be a little wanting though. Both in width and volume, the Rubena tires fall a tad short. However; in terms of how the tires actually ride and perform, they are definitely amongst the high end tires we have tested here on the site. Compounds are spot on, casing feel is very nice, and tread patterns are well thought out. My personal favorite so far is the Kratos, mostly due to its ride feel and outstanding grip. The Scylla is a great choice for those who ride on mostly hard packed dirt and like to go fast. A bit of a specialist tire, but very good in that narrow window of use.
Stay tuned for a Final Review where I will try these tires on a couple different wheels and bikes to get a feel for fitments and performances on different types of bikes.
Note: Rubena sent these tires for test/review at no charge to Twenty Nine Inches. We are not being paid, nor bribed for this review. We will strive to give our honest thoughts and opinions throughout.