Review: 6 of the Best Gravity-Oriented Mud Tires

Mud tires are a bit of a specialty component that are designed for the nastiest conditions, times when traction takes priority over everything else. One catch is that while they give you superior traction through bog and clay, the tall, widely spaced knobs tend to be less than ideal for bare rock and polished roots. However, not all tires are made the same.

A primary reason that you don’t see these types of tires rolling around your local bike park as frequently as the conditions may call for is, besides the obvious - needing to perform a tire swap on the day of the downpour - that they typically roll much slower. For the purposes of this test, we won’t go too deeply into the science of rolling resistance.

Likewise, longevity can be a tough objective to measure due to the amount of time it takes to gather qualitative thoughts about each tire while keeping the testing environment consistent. Due to the testing taking place in the off-season, lift access rides were few and far between. The soggy trails are inherently not as devastating to the lifespan of the tire either, meaning they are valuable to have on hand for when you need them most.

The focus is on all-out traction, feedback from the casing, and how they perform in mixed terrain - you’ll often see some enduro and downhill racers hop back and forth between mud and dry tires, even when the skies might open up, so it’s worth discussing their condition limitations.

The testing took place throughout the Pacific Northwest, where the trail surfaces ranged from slimy clay in Bellingham, to a mixture of sand and fir needles, that some people call loam, around Squamish. There was even a healthy dose of exposed rock and root-infested trails on the North Shore. Pressures ranged from 22 psi, all the way down to 17 for some of the heavier-duty casings.

Although we’re focusing on descending, quite a bit of time was spent using these tires on e-bikes, since the heavier bike is a quick way to assess the stability of a tire.

In order to keep testing even, we chose mud or soft-condition tires in the burliest casing, from six brands: Maxxis Shorty 2, Continental Argotal, Kenda Gran Mudda, Schwalbe Dirty Dan, Specialized Hillbilly, and Michelin’s DH Mud TRL. The first two products, from Maxxis and Continental, are actually not the most aggressive treads in either brand's lineup, however, they are the more commonly used options.

For the measurements, all of the tires were mounted on rims with 30mm internal widths and inflated to 21 psi. The width is measured at the widest edge of the outermost shoulder lug and the depth is the height from the center knob to the casing (when new).

A subjective "suppleness" rating has also been provided where a score of 5/5 would be the most compliant, but not necessarily the least supportive tire laterally, to help compare the tires tested.

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Tire Specifications Overview Chart

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Kenda Gran Mudda AGC

One of the most aggressive tires in the test by appearance is Kenda's mud-specific tire, with large two by two blocks and a square profile. The Gran Mudda uses their Advanced Gravity Casing (AGC) and comes in just one casing and width option per wheel size: 29x2.4” or 27.5x2.4”. Mixed into this formula is a 20mm tall Apex insert at the bead to ward off pinch flats and burping. A lightweight woven aramid material, Kenda Vector Shield (KVS), wraps around the top and sidewalls of the carcass.

Looking further into the tread design, Kenda opts for a dual-compound rubber that has trim lines molded into all of the lugs. Alternating between each row of the center knobs, small ribs are present to shed mud. Horizontal sipes are built into the center knobs and the shoulder knobs also feature small reliefs that run with the rolling direction of the tire.

This was my first experience with Kenda tires in quite some time, and the Gran Mudda positively surprised me in a few ways. The tread is consistent across all surfaces, supportive through the casing, and is still one of the lighter options out there.

The Advanced Gravity Casing allows you to run the tire at lower pressures without folding. This makes the Gran Mudda a solid choice for e-bikes (although we’ll avoid the topic of climbing traction since this tire was neither designed for that purpose nor was that the focus of the test). For gravity riding, though, I found it necessary to run the pressures a few psi lower than normal (sub-20 psi front) because the tire is on the stiffer side - not nearly at the same level as the Michelin DH Mud, but closer to the Dirty Dan. This was a surprise because the Gran Mudda is the lightest tire of the group.

In terms of the tread, the Gran Mudda could almost be considered an intermediate mud-tire because the spikes are tall, yet very wide and supported. For that reason, they grip through the worst slop and are still predictable when you get into rocks and roots. Transitioning to the shoulder knobs in soft, or even harder dirt, wasn’t a precarious move. The huge knobs are sturdy enough that they don’t fold either. When you’re on the brakes, the Gran Mudda anchors down. I’d chalk that up to the square profile that touches more of the trail. That tight spacing did seem to hold a little bit more debris and mud than the Shorty 2 though.

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Most appropriate conditions: Splashy mud soup with mixed surfaces where protection is still required.

Suppleness: 2.5/5

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Maxxis Shorty 2 3CG

Maxxis tires are a crowd favorite when it comes to workmanship with their 3C rubber formulas and casing layup. They’ve applied the same technology to their intermediate mud-spike, the Shorty 2 which was redesigned back in February, 2021.

The tread uses two rows of center knobs that gradually space out further in three steps and then close up again, while the previous generation used one large center rectangle on every third lug. Along the shoulder knobs, the supports were also removed and sipes were added to conform easily. This is said to provide a more consistent feel than before, however, there was no need to divert from the proven 2x60 TPI DH Casing or 3C MaxxGrip rubber compound.



Although Maxxis also makes the Wetscream, a severe mud conditions tire, you’ll most likely see the Shorty 2 used due to its versatility. The width and volume are greater than Wetscream and the knobs are more supportive under higher braking and cornering forces, particularly on bare rock or bike park berms. I’ve been genuinely impressed with the Shorty 2, compared to the original design, and can see why it’s totally suitable in most heinous weather conditions over the Wetscream.

Maxxis also increased the profile to be more square, which makes the cornering traction predictable as you lean the tire over on hard-packed berms that have a slick top layer. Battling rock-armored corners doesn’t feel precarious either as the knobs conform, but are also spaced well enough to clear mud.

There’s no ignoring that the Shorty 2 shares a similar appearance to the Hillbilly. Their ride qualities are similar, yet there are subtle differences between the two. Most notably, the Hillbilly doesn’t hold a straight line as easily through soft organic dirt, where there are rocks and roots lurking under the surface. Even though their numbers on paper are nearly identical, the Shorty 2 profile appears to sit more squarely on the rim, engaging the side knobs sooner.

The 3C MaxxGrip rubber works well in colder temperatures, although for slower speeds, I’d lean towards the 120 TPI DoubleDown casing which is more inclined to conform with less hesitancy. That’s one area where the Hillbilly wins out.

All in all, the Shorty 2 is one of the best tires for wet weather conditions, especially where you may have to deal with variable surfaces or changing track conditions. They’re tacky enough on the rocks, clear mud well, and reasonably supple in cold weather (although a DoubleDown would be suitable for enduro riding).

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Most appropriate conditions: Slick or soft conditions when you still need predictability and bite on variable track surfaces.

Suppleness: 3/5

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Specialized Hillbilly Grid Gravity T9

First popularized by Sam Hill’s unorthodox use of mud tires in dry conditions, the Specialized Hillbilly has evolved into its third design with a new Gripton T9 rubber formula. Closely inspecting the treat pattern will reveal that minor tweaks were made to shoulder knobs, but the primary focus was placed on the damping characteristics of the casing. The height of the blocks has been toned down a smidge and spaced tighter. A supportive rib has been added to alternating shoulder knobs for more support and the profile has been rounded.

I frequently hear the cry for cheaper tires from friends and fellow riders on the trail. I do sympathize that the best traction typically wears the quickest, so I usually reference the value in Specialized’s tire choices. The latest incarnation of the Hillbilly is a quality tire that retails for just $75 USD. Ignoring the fact that they are 25% cheaper than four of the other major players in this test would be rude.


After installing the Hillbilly, its appearance has me questioning its purpose since the shoulder knobs aren’t much taller than Specialized’s dry conditions Butcher tire. The Hillbilly is most similar to intermediate mud tires, like the Shorty 2 and Argotal. Once I put the Hillbilly to dirt though, it became clear that this is more of a wet conditions tire than a proper mud spike.

Those square knobs are spaced out to dig into soft soil decently, but the Hillbilly falls short in the thickest mulch and mud. When the tracks become mega steep and ultra greasy, you’ll want a tire that bites in with authority, like the Schwalbe Dirty Dans or Michelin Mud DH TRLs. If the Hillbilly arrived in a taller, squared-off profile and featured a trim line, like the Kenda Gran Mudda, that would increase its use case for true mud conditions.

With that said, the Hillbilly is still a standout performer for its superior casing absorption. There’s almost an element of Plus-size tire traction at play here, without the unwanted roll. That lug height and casing combo seems to be the ticket for balancing a good amount of bite in some greasy spots and not tippy-toeing on slick rocks.

I’d be more inclined to ride this tire all winter long on an enduro, downhill, or e-bike due to the versatility, similar to the Argotal and Shorty 2. The large volume casing is supple, damped, and still supportive enough for heavier e-bikes, plus the rubber doesn’t tense up in colder temperatures.

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Most appropriate conditions: Cold, wet conditions where equal rock and mud exist

Suppleness: 4/5

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Continental Argotal

Last spring, Continental unveiled a totally revamped lineup of six new tread designs, including the Argotal which is intended for soft conditions. Conti uses a 6-ply, 110 TPI casing construction underneath the open tread design that features ramped center knobs and angled shoulder lugs.

The Argotal comes in either 27.5 or 29” diameters, 2.4 or 2.6” widths, Soft or SuperSoft compounds and three casing weights. The 29x2.4” SuperSoft Argotal, in the DH casing weighs 1325g and costs $99 USD. There are a million possible tire specs to choose from, but Continental only produces the Soft and SuperSoft compounds in the DH casing, regardless of the tread design. So, while you can pick the Argotal for wet days, you’ll need to resort to the heaviest options to get the stickiest.

On that note, one characteristic I’ve noticed with Continental's tires in general is that they reach their peak performance after a few laps. If you grab a brand-new tire, you’ll notice a film or coating that is slippery to the touch, compared to one that’s been broken in; it's likely a coating that's used to help remove the tire from the mold during production. That also makes them trickier to install too.

In terms of tread, there are a few features that catch your eye before putting wheels to dirt. First, the two center knobs are ramped for faster rolling speeds. Secondly, there is a lot of relief. All four blocks across the tread have a hollow space for a larger contact surface, yet remain pliable. On the trail, the tread design is highly predictable, sits square on the rim, and clears well. That all adds up to a decent amount of confidence on off-cambers and slick berms.

Next, is the fact that the shoulder knobs are toed in, opposite to how Schwalbe orientates the lugs on the outside of the Magic Mary. I put this to the test and I installed the Argotal in the reverse direction. It wasn’t a massive difference, but I noticed how the tire was more inclined to bite in, especially on slime over hard-packed dirt.

The most noticeable, and positive benefit of Continental’s downhill tires over the others in the test has to be the suppleness of the casing. That doesn’t mean that the Argotal compromises in support either, though. Specialized’s Hillbilly comes close when conforming to rocks and roots, so it’s no surprise that the most predictable spikey tires in variable conditions were the most supple ones.

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Most appropriate conditions: Cold, wet conditions where equal rock and mud exist

Suppleness: 4/5

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Michelin DH Mud Racing Line

Michelin’s DH Mud TLR has to be one of the wildest-looking tires out there. These mud saws have a huge volume with an open tread design that has dual rows of fang-like blocks that are angled outward. The yellow and blue hot patch denotes the “Racing Line” compound and casing for the most support and protection, often needed in downhill and enduro racing. These weigh in at a hefty 1,450g with a robust 4-ply casing - 100 grams more than any of the other tires in the test. A lighter option of 1,050g is available in the Wild series if you’re looking for a trail-worthy tire.

The tread pattern is extremely spaced out with a moderately round profile. Often, you’ll see pros trimming down the height of the lugs to decrease rolling resistance or reduce the amount they squirm on hard-packed sections of courses. Michelin has molded lines halfway down the center knobs to assist in evenly trimming the height.

Similar to the Wild Racing Line tires that we tested last spring, there is a characteristic that runs through these models of Michelin tires; they’re insanely supportive. The gist of the story is that they work best at high speed. It takes a certain force to deform the tire carcass and for lighter riders, this could mean running sub-20 psi.

The Mud DH TRL are also the only wire bead tires of the group and that could have been one reason why they didn't want to pop on the rim without the use of a compressor. It wasn't a painstaking process involving tie-down straps, but compared to all of the other tires that inflated without special attention, it's worth noting.

On the trail, I found the thick casing to deflect at lower speeds, especially in cold temperatures on cold roots, even more so than the rest of the competitors. What they did well though was regain traction quickly as soon as they grabbed any sight of dirt. The large volume and spikey tread cuts well into soft off cambers and showed no sign of rolling on the rim. I thought that the firm, widely spaced knobs would struggle on hard-packed, but was surprised to find that the profile was just the right amount of round to predictably transition from side to side without any sudden surprises.

This is where the damping and tackiness of the rubber show their strength. The DH Mud TLR comes alive, and reels back in confidence, when you get up to true downhill race speeds. Go fast, pick your braking points wisely, and trust that these tacky spikes will regain traction immediately when they touch dirt again.

The DH Mud TLR is also exceptional at clearing mud and debris. I’m not about to try and measure the amount of earth volume that they dispose of, but I’d rank them up as the best in the test, with the Shorty 2 in a close second place. I wondered if the diagonal knobs help to shed any dirt they pick up as the casing deforms in line or perpendicular to the rim, as opposed to right-angle knobs that would pinch together and possibly hold dirt.

Although I prefaced that this is a mud tire test and we wouldn’t focus on rolling speed, it’s impossible to ignore how the Mud DH ranks last in that category. I believe there’s more at play than just the tall, sticky rubber though. The lack of absorption in the casing simply repels bumps and slows you down.

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Most appropriate conditions: High speed, freshly cut tracks where less rock is present.

Suppleness: 1/5

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Schwalbe Dirty Dan

This savagely sharp tire from Schwalbe resembles those images of Great White sharks about to chomp down on a meal, and that’s exactly the amount of bite they have in the deepest mud conditions. The Dirty Dan has been around for over a decade and is loaded with features.

Since the Dirty Dan is a very specific mud tire, Schwalbe only produces 27.5” and 29”x2.4 options in the softest Addix Ultra Soft compound and Super Downhill casings. The German-designed, Indonesian-made tire is built with cold weather damping in mind, as well as robust protection against punctures.

Schwalbe has arranged the tread in typical two by two staggered rows of center and shoulder lugs, but there’s an additional row lurking along the sidewall too. The tread is the tallest in the test and each block has multiple sipes to conform easily.

Judging by the height of the pointy treads the Dirty Dan has the meanest bite when leaning into mushy corners and shutting down speeds on slippery chutes. I didn’t expect this tire to shine on anything but the deepest bogs or slipperiest clay, but the purple-striped fangs do more than just cut their own ruts.

The tire isn’t overly upset by roots and is more versatile than expected. Any loss of traction on hard objects lying just below the muck is quickly regained when the spikes touch a solid bit of dirt again. As with the Michelin DH Mud TRLs, if you do see exposed rock and roots, you learn to ease off the brakes and trust that the rubber lugs will catch you. The difference between these two is that the Dirty Dan outperforms the Michelin at slower speeds due to the more compliant carcass, however, I’d still love to see the Dirty Dan the lighter, Super Gravity casing.

In fact, the ride is more comparable to the Kenda Gran Mudda, just with a dash more squirm when you hit hardpack dirt. I can see why racers often trim down the Dirty Dan, but I do feel like the additional side knobs provide additional surface contact and support.

It’s no surprise that Schwalbe hasn’t changed the Dirty Dan in over ten years because when you need a tire for the most savage wet weather conditions, this is a premium tread that provides ticks all of the boxes; it grips best in the widest range of mud-types and still clears well. Most importantly though, the rubber doesn’t firm up in cooler temperatures, which is often when the rain comes down the hardest.

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Most appropriate conditions: Primarily, but not limited to, the greasiest grass and deepest duff that you can find.

Suppleness: 2/5

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Top Picks

After spending the majority of the winter trying out all six of these tires, I’m left indecisive about picking just one. Mud conditions in each riding zone can have their own particular circumstances and as specific as mud tires are, each one of these options has strong points that could work best on the day.

When the track conditions are extremely variable and contain multiple surfaces, I’d roll out on the Maxxis Shorty. The knobs have enough support to keep them from folding on hardpack, but are still taller than the Hillbilly, allowing them to bite in deeper. They’re also spaced out well, plus their 3C MaxxGrip rubber is never a letdown. As mentioned, I’d choose the DoubleDown for enduro riding to provide a more supple ride.

For all-out war on the worst track conditions, I loved the Dirty Dan for its ability to find traction in the slickest sections but also conform to roots when asked. The Schwalbe SuperDownhill casing is also a tad more compliant in colder temperatures than the Michelin or Kenda offerings, which aren’t far behind in terms of tracking through the slop.

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Posted In:
Reviews and Tech Reviews Tires Continental Kenda Maxxis Michelin Schwalbe Specialized