Specialized Butcher and Eliminator Radial Tires

It should be no secret that Specialized makes great tires, and yet they may still be underrated. I frequently recommend them to friends who ask, particularly when they lead off their question with a comment about how expensive tires are. The new Specialized Butcher and Eliminator Radial tires retail for 120 CAD, which is not inexpensive, yet is still between 25 and 40 bucks less than Schwalbe’s Radial Magic Mary at various Canadian retailers.

But are they any good?

Let’s back the bus up just a bit. First of all, a quick refresh on what radial tire means in the context of mountain bike tires.

What is a Radial Tire?

Typically, the tires we run use what’s called a bias-ply casing construction, meaning the threads that make up the casing intersect the direction of travel at 45º. You’ll recognize the term radial tire from the car world, and in that case, those threads run perpendicularly to the direction of travel. That is not what these new tires from Specialized are, and the same is true of Schwalbe’s radials. Technically, they’re both still bias-ply, but they use the term radial because the threads are oriented closer to radial than normal. What this orientation means is that the tire can conform better to objects it encounters – it is more flexible, or, the term you always hear used, supple.

Obviously, we like the sound of supple tires, because that means more grip, so why didn’t this come along earlier? The big trade-off with radial casings in a mountain bike application is that in order to get that sweet, sweet suppleness, you sacrifice lateral support. And that means squirming in the corners, pinch flats, instability…bad stuff.

And yeah, you can add more pressure to counteract the lack of lateral support (Specialized referred to this in their literature as pressure tuning), but that starts to interfere with the radial compliance you were chasing in the first place.

Specialized experimented and eventually settled on a 70º casing angle, which achieved what they call their Sweet Spot casing, which they claim increased radial compliance (tire footprint) by 30%, with only a 7% decrease in lateral support. That’s a pretty good trade off.

Also, run the same tire pressure you ran before; no trial and error necessary.

Specialized is careful to point out that despite the Gravity (ie. DH) designation of this casing, these new tires are recommended for trail riders on natural or technical terrain, and those chasing max grip and compliance without lowering their pressures. They are not recommended for bike park or DH riders who seek maximum lateral stiffness, or who prefer a stiff feeling and impact support. Certain hard-hitting shredders and EDR/DH racers, in other words, need not apply, which may explain why Specialized didn’t roll out their Radial casing in some of their DH treads (Cannibal and Hillbilly)…at least yet.

How do they ride?

With all that out of the way, let’s get to the tires themselves. I mounted them onto the S-Works Stumpy 15 EVO I’ve been testing, which allowed for a direct comparison against the non-Radial versions of the same tires (albeit with lighter duty Grid Trail casings) that came stock on that bike. They slid on rather easily and aired up with no drama. Before doing so, I weighed them, and I’m glad I did. On my scale, the Butcher weighed 1,443 grams, which is 113 more than Specialized claims in their literature. The Eliminator at 1,345 grams was only 15 above a claimed 1,330. For DH casings, those weights aren’t egregious, however for tires intended for trail riding…there’s just no getting around it: they’re husky.

And that weight shows. For a 160/145mm travel bike with spirited pedaling manners and wheels that were so fast they felt like they had some low friction voodoo contained within the bearings, the new tires were noticeably porky. Especially when climbing, but even when pumping the bike or carrying flat sections, the bike isn’t as lively. Adding almost a pound to the front tire and 3/4 of a pound of rotating weight to the rear will do that.

The first few rides made that added heft particularly noticeable on the way up. Those first few rides were also plagued by a misbehaving rear brake, which clouded my ability to ride with any kind of aggression or confidence, and thus feel anything to do with the rubber. I got that issue sorted out and then settled into what have been amazing riding conditions out here lately. In a way, that also slowed down my progress in assessing these tires, because the dirt has been so good that any tire you chose to run would have been sitting on pocket aces. Thinking back on recent rides, I’ve been able to pinpoint some moments where the grip these tires are handing out is quite special, indeed. Especially when combined with the confidence and support of those robust Gravity casings, and the damp feel that contributes to a quiet bike, both in handling feel and acoustics.

There have been moments where I chose bad lines and wasn’t punished. There have been some poor landings from which I skated away scot-free. I have doggedly insisted I wouldn’t lose traction in some climbing moments where my not-yet-in-form legs should have failed me, and instead I pushed a little harder into the pedals, felt the frame flex and whip the tires, and was rewarded with the knobs holding on, translating into a scoot forward and up. There is a spot on my favourite loop where I normally smear the rear tire on a slow, tight turn across a piece of off-camber rock, knowing it will break traction briefly, and catch again before it throws me off-line. These radial tires skip the break altogether and just stick the line. The first time it happened, it surprised me a bit, since this is a predictable mini slide even in dry conditions. But the result was that my front tire pursued a tighter line, giving me an extra choice of where to exit the section. Nifty. So yeah, I can’t quantify a “30% larger contact patch,” but I can confirm there’s more mechanical grip. Maybe even enough to justify the added rotational weight for a trail bike.

The other side of these Radial tires is, of course, the lateral support. I typically run 21 or 22psi in my front tire, and 22-25 out back. I’ve had good luck with 21psi up front and 23-24psi in the rear with the Butcher and Eliminator, respectively. I can think of one or two bottom-outs on the rear rim, no pinch flats or rim dings, but otherwise the support is significant, and the ride feel is very damp. This translates to stability, which turns into speed. And that is when the grip has been more apparent in our recent heroic conditions, because at slow speed, you couldn’t miss here over the last month (it’s starting to dry out a lot more now). At higher speeds, I find less degradation in confidence that the tires have my back. There’s more grip there. This radial stuff is legit.

Glancing around at some other chatter out there, you could be led to believe the radial difference is night and day. I wouldn’t go that far. Yes, they’re better. No, I don’t think it’s radial tires or nothing for me in the future. Given the choice of two otherwise identical tires (tread, compound, and weight), the choice is easy. When you start having to sacrifice too much weight, or added weight plus a tread that isn’t suitable for some conditions, you’re pushing into pouring kool-aid on top of your ice cream, and nobody wants grape drink over vanilla – that’s chocolate sauce or espresso territory, nerd.