Bespoken Word: The art of product testing

What goes into the development and testing of a new tire between the brand realizing it needs an update and the review getting published on Bike Perfect. Here’s a behind-the-scenes look at the Butchers from the prototyping level and the testing behind our thoughts on Specialized’s new Butcher T9 trail tire.

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Rewind to mid-September at Innerleithen. It’s the brand new Specialized Stumpjumper launch that the UK marketing team have somehow managed to make happen in super slick, safe style despite all the COVID-19 restrictions. The two new bikes, Specialized Stumpjumper Expert and Specialized Stumpjumper Evo Expert, aren’t the only news either. Underlining them on the trail are the new Specialized Butcher Grid T9 and Specialized Eliminator Grid T7 tires. Or to be most exact on this first ride, the tires appear to be undermining them on the trail. The progressive geometry of the new bikes and first rain-in-a-while slipperiness of the rooty Inners steeps mean several surprise slips and snaps from the new rubber. I’d be tempted to put some of this down to me riding tense due to a recent double broken fibula that I really don’t want to foot dab on, but wide-eyed bottom of descent profanities from a couple of other testers suggest that the new stickier T9 compound isn’t Tweed Valley compliant on initial impressions.

The tire embargo doesn’t lift until after the bike embargo though, which gives me more time to rack up riding hours in more diverse conditions on a fresh set of tires and also dig into the tech behind the new Butcher. The team at Specialized couldn’t have been more helpful either, with US and German tire development and marketing teams throwing several hours into very open Zoom chats. The scope of these included the extended development story behind the new Butcher T9.  How they worked with specialist rubber tuning companies through multiple different formulations of a 15 ingredient recipe to find the damping and durometer sweet spot they wanted. How they teamed up with an entirely new factory and manufacturer on the new Grid Carcass and how different fixed wrap-over sheets and ‘floating’ layers of protection were trialed to see how each performed on the trail. We also talked frankly about where they were looking for improvements on their previous tires and how they used feedback from both regular riders and their pro gravity team as well as their own experience in different conditions to dial in the performance.

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After all that the least I could do was give the tires a second chance on trails I knew much better to give more context against other rubber rather than the initial Southern Scottish slip ’n’ slide. My leg had healed enough to transition from a fragile and hysterically hypersensitive low-speed compression sensor into a more loadable limb by now too which definitely helped as well. 

Unsurprisingly given my initial experiences I was a bit hesitant fully trusting the new Butcher at first. Even though the carcass felt reasonably stable and the slow rebound compound definitely suggested serious stiction, temperatures were low, the trails were wet and the previous Butcher rarely shone in these conditions. It also reminded me a lot of the original E13 TRS tires which were awesome up to a point - especially on low-speed tech - but then would suddenly let go on the shoulders if pushed too hard. The outstanding damping of the compound and carcass was obvious even before we fitted the wheel to the bike though and tentative first runs naturally progressed into more aggressive angles and higher cornering loads as confidence rapidly grew. As usual, we were benchmarking performance against Maxxis and Schwalbe competitors but the rest of the northern test team and I were also switching around with Bontrager, Michelin, and other yet-to-be-launched options. 

Thanks to the random weather of the early year we were pushing the tires in all conditions from frozen solid to snow and slop and clogging filth, and the Butcher was still impressing. With the tread pattern unchanged from the previous Butcher it’s not a full mud tire (look at Specialized’s Hill Billy for that) but mechanical traction is decent in most conditions and they clear quick enough to bite predictably. While I’m not the most aggressive bar dragger, I made sure I lent the Butcher to steezier riders who regularly risk their grips on the apex (if you’ve seen the recently slammed berm Tallboy ad from Stif Cycles that’s actually the test Butcher on the front of that bike) and they couldn’t get it to unhook either. Now things are warmer and looser they certainly stretch and smear a bit at extremes at which point the slow rebound rubber can feel a bit weird compared to something harder or better buttressed but they’ve yet to step out without provocation as they did in Peebles.

Obviously, that brings up the question about why these tires seem to be doing better than the first set. It sometimes takes a while for a tire to lose the coating of slippery release compound that they spray into the molds before loading the tread rubber in. Or maybe it does have an Achilles heel of a particular temp/moistness that we haven’t replicated yet somehow. 

Because of that start - and because I was the first to stick my neck on the line with a review of these tires I’ve been particularly thorough with the testing - as far as COVID-19 travel restrictions and climate have allowed - and I’ve got a bunch of other trusted riders backing me up with very positive feedback so far. It even rolls pretty well for a sticky tire, it’s relatively light and, unlike most tires, it blows up bigger than claimed. Add a reasonable price and I’m happy to stand by the pretty stellar score for this tire. And that was before they released the tan wall ‘Soil Searcher’ versions where a portion of the price goes towards trail maintenance and advocacy which is a really neat move by Specialized that echoes increasing amounts of brands committing sales cash to sustain and grow mountain biking at a literal grassroots level.

The beauty of the internet is that nothing is ever fixed though, so if I - or Ryan who’s sharing test riding duty on the tires at the moment - does find an issue with the Butcher we can update the review immediately. It also means that in a week or so we can finally spring the news on several other tires from Specialized and other brands we’ve been testing for months. 

Don’t expect all those reviews to be quite as positive though, which is frankly a relief as it’s hard to look like you’re not just gushing about everything if brands just keep making better and better stuff. The subject of score creep is a whole other essay I need to get round to writing though, so stay tuned for that one soon.

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