We got a look at Pirelli’s first mountain bike tyre back in February 2019 when Pirelli whisked us off to Mount Etna on the island of Sicily. You can read about our weather-plagued experience and first ride impressions of the Pirelli MTB M tyre here — the one designed for mixed trail conditions.
Pirelli Scorpion MTB tyre specifications and details
Pirelli’s mountain bike tyres are unusual in that there isn’t one tyre in the range designed for wet weather, dry conditions or any other type of meteorological circumstances our humble planet can muster up. Instead, the tyre’s name denotes the sort of terrain it’s designed for — H for hard, M for mixed, S for soft and R for rear-specific tread.
For example, if you ride hard-pack clay, rocks or dirt, regardless of whether it’s wet or dry, Pirelli says you should go for the H tyre.
Similarly, if you ride some soft and hard terrain types — think trail centres with the odd loam-based adventure into the woods — then select the M tyre.
It claims the R tyre is similar in performance to the M but has larger central ramps for braking.
Every Scorpion MTB tyre uses Pirelli’s own SmartGrip rubber compound that means, Pirelli claims, the tyre’s performance isn’t altered when the weather or temperature changes.
Not only that, Pirelli says its tyres are one single compound, which is at the heart of Pirelli’s claims that its tyres are terrain, rather than conditions, specific.
Pirelli Scorpion MTB S tyre specifications and details
What about the S tyre I’ve tested? Pirelli says it’s best suited to, yes you guessed it, soft terrain. That includes anything from wet mud right the way through to sand. The S has the most aggressive tread pattern in Pirelli’s range, designed to bite into soft ground.
I tested the S because it seemed like the most suitable rubber for the sort of trails and type of conditions I ride in the UK. I opted for the 2.4in wide 29er 60TPI tubeless-ready tyre, which tipped the scales at 899g.
The tread patterns become more aggressive as the tyre’s width increases from the smallest 2.2in to 2.4in and up to the widest 2.6in (which isn’t currently available).
Although these changes in tread pattern are hard to spot at first glance, take a longer look at the tyre and the subtle differences become apparent.
For the sake of simple comparison, the Pirelli Scorpion S in 2.4in looks like a mix of Schwalbe’s Nobby Nic and Maxxis’ Minion DHF tyres.
Pirelli Scorpion MTB S tyre performance
I chose to mount the Scorpion MTB S to the front of my bike, swapping out my favourite Maxxis Minion DHF 2.5WT 3C EXO tubeless tyre. On the rear, I did put on a Pirelli MTB R tyre but this review is going to concentrate on the performance of the S.
Getting the Scorpion S to successfully seat and seal on my tubeless Race Face ARC30 rims didn’t require a high-volume pump like an Airshot. Instead, a standard pump put out enough air to get the tyre to pop onto the rim after only a few sharp strokes.
The tyre did manage to hold air over a few days, but leave the bike in the shed for longer and it will start to weep pressure.
As someone who doesn’t like the hassle that’s sometimes associated with setting up tubeless tyres, this impressed me a great deal, but did leave me wondering ‘if it’s that easy to get on the rim, surely it’ll just rip right off?’ As it turns out, I needn’t have worried.
I inflated the tyre to my preferred pressure and set out to find its limits. I rode a real mix of terrain including soft, loamy descents, the South West’s best muddy slop and even hard pack trails – despite Pirelli stressing that this tyre isn’t designed for that sort of firm terrain.
First impressions were good and general grip — especially when riding along fire roads or plodding down simple trail centre loops — seems to be consistent and predictable. The carcass’s overall stability was also impressive.
I particularly detest the feeling of a tyre’s carcass wallowing around on the rim — a common sensation I get with thin-casing tubeless tyres – but this wasn’t an issue with the Scorpion.
Not only did the carcass not shift or squirm on the rim’s seat, it also didn’t get ripped, nor did the tyre puncture during the test period, even when I was aiming for the harshest, rockiest trails I could find.
The tyre doesn’t have great grip on greasy or damp ground, and I could feel it scrabbling around and sliding rather than biting in to the dirt. For reference, the aggressively-treaded Schwalbe Magic Mary didn’t generate the same sensation in similar conditions.
This feeling was echoed on other types of soft terrain. I noticed it sailing over the top of the ground rather than biting into it, and not managing to tear its way through the soft loam I was riding.
I’d happily go out on a limb and say that the Scorpion S probably isn’t best suited to extremely wet, soft terrain, somewhat thwarting the claims of superior grip in these conditions.
Despite these slip and slide sensations, the tyre was deceptively grippy in less extreme conditions, especially considering how unpronounced its tread pattern is — at least compared to some of the competition that’s claimed to be for wet, soft conditions.
And it would be fair to say that it slides much further down the line and at an angle far more leant over than I imagined. Considering this tyre isn’t an all-out enduro or DH-specific beast, it doesn’t do too badly in very gnarly conditions.
When you do start to slide, though, the transition from grip to drift is very gradual. The tyre’s profile isn’t square and the side knobs aren’t too blocky. This helps it to predictably enter slides without a sudden drop off in grip.
Similarly, it’s very easy to bring the tyre back under control once it has entered a drift with some simple weight shifts.
This was one of my favourite qualities of the tyre and made significant redemption for its, at times, less-than-ideal traction.
On dryer, hard-pack terrain the tyre offered good, predictable grip that was akin to how I’d expect a knobbly tyre to perform. And at no point did I think the knobs were too big, and they didn’t suffer from deformation and bending — a characteristic sometimes created by blocky tread on hard-pack surfaces.
Pirelli Scorpion MTB S tyre bottom line
The Scorpion certainly impressed me with how much grip its rather modest tread offered, but its limits were easy to find, and when pitched against the sort of tyres you’ve probably been riding in soft and wet conditions since the start of time — think Maxxis High Roller, Shorty or a Minion DHRII or Schwalbe’s Magic Mary or Hans Dampf — it doesn’t really stand a chance.
Pitch it against lighter, more trail-orientated tyres such as the Maxxis Ardent or Forekaster, Schwalbe’s Nobby Nic or Rapid Rob and it’s suddenly leagues ahead, offering great traction on a very wide variety of trail conditions. That includes everything from muddy slop right the way through to dry hard-pack as long as you aren’t absolutely gunning it.
My main problem is with Pirelli’s desire to re-write the rule book on how we think about tyres. In its defence, its mission is admirable and should make life easier for the end consumer, but in the conditions-specific world of mountain biking it doesn’t quite work.
Equally, the assertion that this tyre works as well in the wet as it does in the dry — as long as the ground is soft — doesn’t ring true and this seems to be a virtually impossible target to reach.
We all know that a mud spike tyre will be best when it’s wet and soft but will struggle on dry trails. Likewise, a Maxxis Minion DHF that’s most at home on hard-pack terrain isn’t going to grip in gloopy mud.
In trying to provide a solution for a lot of different conditions it’s managed to make a tyre that’s not a master of any one thing.
Maybe that’s a backhanded compliment, though, and if you’re not that bothered about outright condition-specific performance, the Scorpion S is a solid jack-of-all-trades tyre that’ll get the job done, just not as well as a specialist offering.