Pirelli is a brand name that is synonymous with modern Formula One, MotoGP, and Motocross racing at the highest level. However, early 2019 saw the launch of its Scorpion MTB range, bringing decades of experience in designing high-performance tyres to mountain bikes. Since the launch, the range of compounds and casings have undergone minor revisions and additions to improve overall traction, durability and sidewall support, however the tread patterns have remained largely the same. 

Pirelli’s Scorpion range covers all riding disciplines from XC to DH and just about every sub-category in between, but how do you choose the right tyre for your riding style and the terrain at hand? 

Pirelli Scorpion mountain bike tyre overview

While the vast array of tread patterns, casings and compounds may seem overwhelming at first, Pirelli tried to simplify the choice by categorising its tyres for their intended use — XC, trail, enduro, race enduro and DH. 

In each category, Pirelli has various options for tread patterns based on terrain broken down below:

• Scorpion M | Mixed conditions — available in all categories
• Scorpion S | Soft conditions — available in all categories
• Scorpion R | Designed specifically as a rear tyre — available in XC, trail and enduro categories
• Scorpion T | Maximum Traction — available in Race Enduro and DH categories
• Scorpion MUD | pretty self-explanatory — only available in DH category
• Scorpion H | Hard conditions — only available in XC category 

Pirelli aims to take some of the guesswork out by offering the most suitable casing and rubber compound within its range to serve the use category and conditions. However, certain options have multiple casing options to choose from. 

Pirelli Scorpion Rubber Compounds 

Pirelli has taken a slightly different approach with its rubber compounds, and all of its tyres are based around a single compound as opposed to using multiple layers of different durometer rubber. Pirelli claims that a single compound provides superior consistency throughout the life of the tyre, compared to having the outermost layer wear down, exposing harder/stiffer rubber, and subsequently having an inconsistent tyre feel. 

SmartGRIP is Pirelli’s core compound option. It claims to blend two opposing features: superior mechanical grip in wet and dry conditions and chemical grip in wet conditions, all while maintaining tear and puncture resistance. SmartGRIP is found across the XC, trail, and enduro tread patterns. While not an apples-for-apples comparison, this is most comparable to Maxxis’ MaxxTerra rubber.

As the label suggests, the SmartGRIP Gravity compound is formulated specifically for gravity-orientated riding, featuring a softer compound of rubber for increased traction in wet and dry conditions. On paper, there is a marginal sacrifice in rolling resistance compared to the SmartGRIP compound. For the purpose of comparison, the SmartGRIP compound would sit squarely in between Maxxis’ MaxxTerra and MaxxGrip compounds, blending of the characteristics of each. 

SmartEVO DH is Pirelli’s flagship gravity compound, which has been formulated with knowledge drawn from the Italian outfit’s Motorcross and Rally World Championship teams, alongside testing with its sponsored Enduro and Downhill teams. The SmartEVO DH compound features a super soft temperature stable rubber, resulting in maximum traction regardless of the terrain or temperature conditions. This compound is available in both the Enduro and DH tread patterns in the DualWall and DuallWall+ casings respectively. 

Pirelli Scorpion Casing Options

Dedicated to XC racing only, LiteWall has been designed as Pirelli’s featherweight tyre casing targeted specifically for XC applications and maximum speed. Featuring a 120tpi casing with no additional puncture protection, this casing demands an accurate and sharp riding style.

ProWall is the most versatile carcass in the lineup, built around a 60 or 120tpi carcass with an extra layer of nylon for puncture protection and sidewall stability, even at lower pressures. Due to the ProWall’s versatility, it is available in Pirelli’s XC, Trail and Enduro tread patterns, and would be most comparable to Maxxis’ EXO. 

The HardWall casing takes the features of the ProWall and turns them up a notch, with bead-to-bead protection and an additional hard rubber insert above the bead. The result is increased resistance to those pesky torn bead tyre blowouts. HardWall casings are offered exclusively to the Enduro tread patterns as a lighter-weight alternative to the thicker and heavier casing options. In terms of comparison, think Maxxis’ EXO+ casing with additional protection.

The DualWall casing was specifically designed for enduro racing, featuring a 120tpi double-ply carcass with additional rubber inserts around the bead. Pirelli says DualWall offers increased puncture protection and sidewall support without the increased weight from thicker casing options. DualWall is most similar to Maxxis’ Double Down casing, being one notch down from their heaviest/toughest offering.

As Pirelli’s most aggressive casing for enduro and DH racing,  DualWall+ features a 60tpi complete double-wall carcass along with additional rubber inserts at the bead, resulting in the best puncture protection and sidewall support the Italian brand has to offer. Available in the DH tread options, the DualWall+ casing is clearly targeted at gravity riding and racing at the highest level.  

Tested Combinations and Impressions

The Flow Mountain Bike team have been putting in the hard yards over the past several months, riding a variety of tyres across several different bikes to see how Pirelli’s tyres stack up. While this is by no means a complete review of its entire range, it does cover what we believe to be the most suitable configurations for Aussie conditions.

• Scorpion XC RC front and rear (SmartGrip/ProWall) – Canyon Exceed 
• Scorpion Enduro M front / Enduro R rear (SmartGripGravity/ProWall Front, SmartGrip/ProWall Rear) – Santa Cruz Tallboy
• Scorpion Enduro S front / Enduro M rear (SmartGrip Gravity/HardWall Front, SmartGrip/HardWall Rear) – Santa Cruz Nomad
• Scorpion Race Enduro S front / Race Enduro T rear (SmartEvo DH/DualWall) – Ibis HD6

  

  

  

Installation

Fitting all of the Scorpion tyres to the test bikes went as well as it could have, requiring a standard serving of sealant and a tubeless specific floor pump with an expansion chamber. In hindsight, we’re sure they all would have inflated with a standard pump and bit of elbow grease, but no point in making it harder than it needs to be. All of the tyres seated completely without excessive pressure. The installation onto the two pairs of carbon Reserve carbon wheels were just as simple as the aluminium wheels. Pirellis have been known to be pretty darn tight fitting in the past, and we’ve had a fair few snapped tyre levers, bloody knuckles and more than a few tears shed trying to get them onto carbon wheels. It seems the brand has tweaked something as that was not our experience this time around — kudos to Pirelli! 

Pirelli Scorpion XC RC | Canyon Exceed

After removing the stock Schwalbe Rocket Ron tyres from the Canyon Exceed (non-tubeless ready, miraculously held tubeless until the day the Pirelli’s arrived, coincidence?) and mounting up the Scorpion XC RC’s, the intention of these tyres became immediately apparent — speed. 

The Scorpion XC RC features a single row of low central knobs, accompanied by angled rows of intermediate knobs for transitioning to the edge of the tyre, where cornering lugs are grouped in pairs, with a minor gap between them. The ProWall casings are feathery with a claimed total weight of 660g per tyre, however, they have proved to be far more durable than originally expected and have survived plug-free so far over some long, hard rides and some questionable terrain. This kind of tyre is best suited to loose-over-hardpack conditions which is exactly what we had for the majority of testing up here in Bright in the Victoria High Country. 

Climbing with the Scorpion XC RC tyres is exactly as you would expect from a race-focused XC tyre, extremely fast with razor-sharp precision. The tightly spaced and tapered central knobs and angled intermediate knobs provide an excellent platform for carrying maximum speed through rolling terrain, with minimal apparent rolling resistance. You’ll need to be on your game because these suckers turn over fast! Climbing technical pinches on the RC tyres was impressive given their low overall tread height and tight spacing between knobs. But they also required careful line choice and correct speed management to get the most out of them. This rings true for any comparable XC tyre out there.

Descending on the RCs would be best described as lively, delivering the right amount of cornering grip and braking traction you’d expect out of such a fast-rolling tyre. As the speeds increased and the terrain became looser, braking points became critical to manage speed and maintain traction. They do well under heavy braking but obviously have a well-defined limit, which can easily be found with a fist full of brake.

The RCs became skittish and nervous over the loose rocks on rough fire-roads, which isn’t overly surprising seeing as it isn’t the terrain they are intended for, but may often find themselves in. Despite the sidewalls being reasonably thin, we had no punctures throughout testing and they provided a reasonable amount of support when cornering without any undue squirming or rolling. 

There is one word that floats around in our brains when trying to summarise the Scorpion XC RC combination, FAST. It is very clear that Pirelli has brought across its experience in high-performance racing when developing these tyres, resulting in extremely fast and responsive rolling stock. Keep them within the terrain they were designed for and these tyres are fighting the top contenders when considering XC rubber. 

Pirelli Scorpion Enduro M and R | Santa Cruz Tallboy

At first there were some questions as to how the Scorpion Enduro M and R combination would go on a Santa Cruz Tallboy. Being a more aggressive tyre compared to the Maxxis Forekaster combination replaced, with a fear of slowing down some of the Tallboy’s sharp handling characteristics. Installation was simple, with the Enduro M on the front measuring 2.25in, and the Enduro R on the rear measuring 2.35in after initial inflation, which settled out to the stated 2.4in after the first ride and sitting overnight. 

The Scorpion M in the SmartGrip Gravity/ProWall configuration was fitted to the front of the Tallboy and sees alternating grouped and spaced central lugs, generously sized intermediate knobs, and large alternating concave and convex cornering lugs. This was paired with the Scorpion R SmartGrip/ProWall configuration on the rear, being Pirelli’s rear-specific tread pattern designed specifically for braking traction and rolling efficiency, with a closely spaced lug and rounded profile.

The majority of the testing on the Tallboy was completed within Mystic MTB park in Bright, including a mixture of hard-packed clay, loose pine needles and a wide variety of trails. Those preconceived hesitations were quickly dismissed following the first climb on the Tallboy, as the Enduro M and R provided a fast platform to zip up the climbs and accelerate out of corners with ease. Rolling efficiency was impressive, and although hard to quantify, offered a noticeable improvement over the Maxxis Forekasters they replaced — which certainly aren’t slow.

On the descents, the Scorpion M and R’s gave the Tallboy razor-sharp handling and complimented its character as a trail weapon — certainly an unexpected trait given the aggressive tread.

Under heavy braking, the Scorpion R does an admirable job of maintaining traction and resisting stepping out, although braking points became more critical due to the increase in overall speed the Tallboy was carrying. The Scorpion M provides a level of stability and confidence similar to the Forekasters. As the speeds increased, so do did the demands on the tyre, and the Tallboy required very precise rider inputs to manage the traction available.

The Scorpion M has a predictable and recoverable point at which it breaks away in dry hard-packed and loose-over hard conditions. But due to the extremely dry weather we’ve seen in the High Country over the past month, no testing was undertaken in the wet. 

The result? A very fast set of trail/light enduro tyres that offer a commendable amount of traction for their respective rolling resistance. The Scorpion M and R combination complimented the Tallboy as a trail scalpel with razor sharp precision, but beware of the limits at the new-found higher speeds as it can be easy to get carried away and assume infinite grip is available. 

Pirelli Scorpion Enduro S and R | Santa Cruz Nomad

Fitting the Scorpion S and R combination to the Reserve 30HD wheels on the Nomad was a simple affair, although it let off an earth-shattering snap when the beads of the tyres seated to the rims at around 30psi. Both the Scorpion S and Scorpion R measured 2.35in when first installed, however expanded out to the quoted 2.4in after the first ride and sitting overnight. Pressures were set at 21psi and 25psi for testing. 

The Scorpion S is dubbed as their soft terrain tyre for loamy dirt and mud, featuring a tall profile and widely spaced tread pattern to slice through the fluffy top layers to the firmer soil below. The HardWall casing is noticeably thicker than the ProWall tested on the Tallboy, and has a marginally more secure feeling on the trail and under heavy cornering.

The majority of testing was conducted throughout summer,  so deep mud was off the cards, and the conditions in the Victorian High Country wouldn’t really be described as soft loam — even at the best of times. Although we did put some solid testing laps in at Mount Buller, which served up a healthy heaping of late-season deep, loose dust. The Scorpion R tested on the Nomad has the same tread pattern and compound that was featured on the Tallboy, but with a HardWall casing as opposed to the lighter ProWall option. Being a rear-specific tyre, the overall layout of the tread is designed for rolling efficiency and traction under braking.

Climbing on the Nomad was impressive compared to other enduro-orientated tyres on the market, providing fast acceleration and a zippy feeling on rolling terrain, with noticeably less rolling resistance. These are traits not typically associated with enduro tyres but are what the tight tread spacing and compound of the Scorpion R provide.

Traction under technical climbing was respectable and the rolling efficiency helped to carry additional speed to winch up trickier sections of trail. Similar to what was experienced on the Tallboy, the Scorpion R struggled a little when climbing in deeper dustier sections of singletrack or with large loose rocks, requring careful weight balance and distribution to maintain traction. 

With gravity behind you, the Scorpion S holds traction in loose terrain and gave the front end of the Nomad a precise, sharp feel with a notable increase in damping and support compared to the ProWall casing tyres. With the wide spacing between the centre and outer lugs, the transition between them feels unnervingly vague when dipping into a corner on hardpacked dirt. But, these tyres are designed for soft terrain afterall, and in those conditions, this transition is not apparent. 

Overall grip and stability are solid but aren’t quite at the level otherwise found on the front end of an enduro race bike. Same goes with the rear, the traction was adequate but not excellent, and provided a predictable breakaway point when purposefully drifting with the rear.

This may appear as a negative, but remember Pirelli also offers a race enduro range of tyres featuring softer compounds and grippier tread patterns. The fact that these measure up reasonably close on traction and bring a significant reduction in rolling resistance compared to other manufacturers’ premium offerings should not go unnoticed. 

Pirelli Scorpion Race Enduro M and T | Ibis HD6

For Mick’s recent Ibid HD6 build he opted for the premium Enduro Race offerings from Pirelli in the Mixed and Traction tread patterns for the front and rear respectively. The tyres feature the super soft SmartEVO DH compound and prioritise grip over durability and rolling speed. Without sounding like a broken record, installation onto the Zipp 3Zero Moto wheels was a breeze and seated with a splash of sealant and a track pump. 

Suprise surprise, with the gooey SmartEVO DH compound these were certainly not the fastest rolling tyres, but compared to similar combo like the Assegai/DHRII in the MaxxGrip compound, the Pirellis are no slouch either. The Traction rear tyre performed impressively when aimed uphill into technical rocky and root-covered climbs, resisting spinning and breaking traction when out of the saddle, with the soft lugs conforming to the obstacles or biting into the dirt. 

Also without surprise, the Race Enduro tyres came alive when pointed downhill, delivering giggle-inducing amounts of traction as the tyres claw into the terrain. The Race Enduro M fitted to the front performed exceptionally well in dry gravel and loose-over hardpack, where most tyres will struggle to maintain traction and is what stuck out the most over comparable offerings. Under hard braking, the Scorpion Race Enduros resisted skipping out — especially the rear tyre — with its deep paddle-shaped centre knobs, and that prompted late braking, and riding with aggression and confidence. The double-ply 120tpi carcass within the DualWall casing was stable and supportive, providing a comfortable level of compliance that would be most similar to the Maxxis Double-Down casing. 

The aggressive tread pattern and super soft rubber made successive manoeuvres at moderate speeds more demanding in some scenarios, and their insistence to maintain traction can sometimes feel overkill depending on the terrain. Like anything, it is about choosing the right tool for the job, and if ploughing down the roughest rowdiest terrain — stopwatch or not — is your jam, then these are some of the best tyres currently available. 

Flow’s Verdict

Across the range, it is abundantly clear where Pirelli has come from, and its focus on high-performance products and racing at the highest level. All of the tyres tested have an underlying sense of speed to them, and deliver a commendable amount of traction in their respective category. 

There is no perfect tyre for every scenario, but choosing the right one is about selecting a suitable tool for the job. Here are our final thoughts about where each of these tyres will thrive. 

Scorpion XC RC | Best suited to XC hardtails or dual suspension ~100mm-120mm XC bikes for riders looking for an extremely fast tyre in a variety of conditions. It excels in hard-packed conditions.

Scorpion Enduro M and R | Well suited for ~120-140mm downcountry or trail bikes in the ProWall casing, or ~150-160mm Enduro bikes in the HardWall casing, and riders chasing extra speed and sharp handling but still want predictable traction. This configuration will suit the majority of riders in Australian conditions.

Scorpion Enduro S and R | Well built for ~150-160mm trail/enduro bikes being ridden in soft/loose terrain. For additional traction the Enduro S would work well as a rear tyre, however it sacrafices overall rolling efficiency. Aggressive or heavy riders may find the HardWall casing too soft for their riding style, going for a Race Enduro tyre with the DualWall casing would be a better option here. 

Scorpion Race Enduro M and T | Gravity fiends rejoice, these are up there with the grippiest tyres about, and will be best suited to ~160-180mm enduro bikes. Riders who are racing against the clock in the roughest, loosest conditions will appreciate the level of traction and confidence these deliver, but be aware the increase in traction comes at a cost, and may require additional rider input for successive slow-speed manoeuvres as drifting is no longer an option.