Tire Evaluation Criteria
JConcepts' 1.9" Tusk tires being put through the paces on our Technical Rock.
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After completing more than two dozen tire reviews, we felt it was time to develop a ranking system in efforts to identify which tires excelled in our desert terrain and which tires came up short.
We also wanted to highlight tires which demonstrate an exceedingly high-level of quality and uniqueness in design, while also pointing out those which lack attention to detail in the same areas. Our approach for this is to evaluate each tire against a standardized set of criteria based on six unique categories. These measure design characteristics, construction details, as well as assessing performance on two specific rock types encountered on our trail system at Badrock Ridge. |
Tires which exhibit desirable traits or high levels of performance are awarded more points per category than tires which do not. Once the scoring is complete, we total up the points for a final overall score where there is a possible 100 points to achieve.
The testing categories are not weighted the same, in that more points are awarded for categories which we deem to be the most critical and relevant to overall performance, while fewer points are associated with categories for relevant traits, but which have a smaller contribution to performance out on the trail. Simply put, some things matter more than others, but all six categories are factors in the assessment of a tire.
The testing categories are not weighted the same, in that more points are awarded for categories which we deem to be the most critical and relevant to overall performance, while fewer points are associated with categories for relevant traits, but which have a smaller contribution to performance out on the trail. Simply put, some things matter more than others, but all six categories are factors in the assessment of a tire.
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Evaluation Categories
After a good amount of discussion on the topic, we’ve established six categories which we feel are the most important and relevant to achieving a high level of performance on our terrain. The categories are:
These six categories address both the physical attributes of the tire as well as the tire’s performance on two distinctly different rock surfaces. |
The tight tread pattern of the JConcept's 2.2" Scorpios attacking the smooth sandstone.
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Steering clear of the watering holes while out testing the Pro-Line Racing Hyrax 2.9" tires.
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Excluded from Testing
We do not test a tire's performance on wet surfaces in that flowing or standing water is uncommon in our desert landscape. We also do not specifically test tires in mud, sand, or small loose rock. Mud falls into the same category as wet terrain, uncommon in our environment, and in all reality, we have yet to see any crawler tires struggle with sand or small rock. Finally, we didn’t assess a tire’s performance on small single-rock formations, often referred to as “bouldering.” It’s not the kind of rock crawling we are terribly interested in pursuing, and more so the truck’s wheelbase and suspension geometry play a much bigger role than tires in this type of crawling. |
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Technical Rock 30/30
The Mojave Desert is home to some spectacular sandstone formations, with the Red Rock national conservation area being one of the most famous of these formations in our area. Just outside of this conservation area, smaller sandstone formations just out from the local hillsides, forming our main crawling system, locally known as Badrock Ridge. These 200-million-year-old sandstone formations are actually old sand dunes which have undergone the process of Lithification, where pressure and mineral deposits have turned the layers of sand into solid rock. Over time, weathering and seismic events have broken down and eroded the sandstone formations, leaving behind a uniquely challenging surface we call "Technical Rock." |
Better bring your A-game to Highline Trail; it's as technical as it gets for rock crawling.
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Devil's Haircut trail isn't for the faint of heart.
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Technical Rock, as we define the terrain, is heavily eroded sandstone with deep under cuts, carved-out water pockets, and a deeply fractured, tilted surface.
This type of rock challenges every aspect of a crawler, from skid clearance, weight distribution, and suspension settings. Tire quality plays a highly important role in this terrain where you need every bit of traction that’s available. We spend the greatest amount of time testing tires on Technical Rock, and in our tire reviews you will see at least half a dozen or more names of our most challenging trails cutting through Technical Rock terrain. Trails like Devil’s Haircut, El Arbol Perdido, Highline Trail, and Creosote Butte are just a few of our favorite trails, and these exemplify what Technical Rock crawling is all about. |
The demands on a tire are multifaceted; tires can’t just be sticky to do well on this kind of rock. They also need to have a tread pattern which can grab hold of the rock's imperfections for traction. Spacing between lugs allows enough room for the lugs to fold around the rock, while robust sidewall lug patterns help wedge the wheel against rock walls or tall outcroppings.
Since this is the essence of crawling in our terrain, we’ve assigned the greatest number of points for this category; 30 points are possible.
Since this is the essence of crawling in our terrain, we’ve assigned the greatest number of points for this category; 30 points are possible.
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Large Slab (Slick Rock) 20/20
Depending on the water runoff paths or even recent seismic events, you can come across large slabs of smooth sandstone which present their own set of unique challenges. At Badrock Ridge, we have a number of these large sandstone surfaces which are oddly smooth and tilted up at varying angles. Traction on this smooth surface is highly dependent on the rubber compound. Soft, sticky rubber sticks to the rock, creating enough traction to prevent the truck from sliding back down the side of the formation. The more rubber you can put to the rock, the better. Tight tread patterns do well on this rock, as well as the thinner, more flexible tire carcasses. This challenging surface merits a possible 20 points towards the overall score. |
Pro-Line Racing's BFG Krawlers being pushed to their traction limits on slick rock.
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Pro-Line Racing Super Swampers on the SCX-6 Honcho.
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Tire Construction Quality & Appearance 20/20
Many RC tire companies go to great lengths incorporating scale details into their tire molds, bringing to the consumer not only a highly capable crawling tire ( tread pattern / rubber compound ), but also something with a strong “curb appeal” and scale detail. In competitive rock crawling, there are a few classes which either mandate that the tire be based on a 1:1 version, or award extra points for “scale” realism. Companies like Pro-Line Racing choose to pay a licensing fee to secure the rights and copy the original pattern, striving to get every small detail nailed down on their crawler tire. Pro-Line’s BFG Krawler T/A is an excellent example of this; nearly perfect in every detail when compared to their 1:1 counterpart. |
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Along with this detail, there is the overall precision of the mold and trimming of the final product to consider.
Some RC tires are poorly molded, showing mismatched tread patterns from either side of the tire or excessive rubber flashing hanging from the tire’s bead or down the middle tread seam. Tires like this will receive lower scores for this grading section. Contributing to a higher score, extra detail in the lettering on the side of the tire, along with clean, crisp molding lines as well as raised lettering or additional molded-in detail is noted. |
These Duratrax Deep Woods didn't have the construction quality needed for a high-level of performance.
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Unfortunately, careful attention to detail on a tire can be ruined by poor construction quality. Overly thick or excessively thin tire carcasses greatly hamper a tire’s performance, either resulting in too little flexibility or a loose, floppy feel out on the rocks.
An example of this are the 2.2” Duratrax Deep Woods tires. While they showcase stunning looks, the carcass is far too thin, resulting in poor performance out on the trail.
We have chosen to score this heavily, with a possible 20 points in this category. Tire quality is paramount in achieving excellent performance, and good, detailed scale looks are key for many drivers.
An example of this are the 2.2” Duratrax Deep Woods tires. While they showcase stunning looks, the carcass is far too thin, resulting in poor performance out on the trail.
We have chosen to score this heavily, with a possible 20 points in this category. Tire quality is paramount in achieving excellent performance, and good, detailed scale looks are key for many drivers.
The Antero outfitted with a set of JConcept's Ruptures is sticking to this rock like glue, and thankfully so; we're 20' up from the ground below.
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Rubber Compound 20/20
When it comes to “rubber meeting the road”, our first thought is mostly concerned with exactly what kind of rubber compound are we talking about. Rubber compound is such a critical element in crawler tire performance that we reworked the scoring range of other categories in order to award twenty points to this category. Initially, we had it at ten points, but after further thought, it seemed inadequate. Soft, sticky rubber is essential for traction on our rocks, especially smooth sandstone surfaces. Hard rubber compounds struggle in this terrain, making the tire of little use outside of casual trailing or small rock crawling. Conversely, overly soft rubber compounds can suffer in elevated temperatures, so much so that more than a few RC companies have suggested temperature ranges for tire use. We will delve into that for some of our reviews and share our findings. Most RC companies have rubber compound sorted out to some extent, but the inexplicable naming convention used for the various compounds between manufacturers make little sense. |
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To further complicate matters, there are clear-cut contradictions in the rubber-naming conventions between manufacturers. An example:
While this relatively obvious pitfall can be avoided, things get a bit trickier when you’re looking at rubber compounds with names such as Alien Kompound or Zuper Duper Kompound; both being from the suite of creative descriptions found in Pit Bull RC’s line of crawler tire rubber compounds. They are about as intuitive as they are entertaining. Luckily, we are here to help. |
Traxxas has named this tire compound as S1, representing their softest rock crawling rubber compound.
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In our scoring criteria for this category, we will identify the rubber compound used, where it lands on that companies’ rubber compound chart and naming convention, and how it performed on our rocks. There are a possible 20 points awarded in this category.
These 2.9" Hyrax from Pro-Line Racing have worn down considerably since their first day out on the trail.
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Tread Life 5/5
There’s always a tradeoff between performance and longevity, and typically the better a tire performs, the shorter the functional lifespan becomes. Soft rubber compounds and finely detailed tread patterns wear quickly when pitted against the abrasive surfaces of our desert rock. Squared corners on tire lugs are usually the first to go, with detailed siping and tall geometrical shapes following soon thereafter. Eventually the tire’s lugs become rounded over, wearing down to small nubs and losing their rock-gripping performance. Another contributing factor to tire wear is the amount of surface contact, known as the contact patch, with the rock. Open, aggressive tread patterns have a relatively small contact patch on a flat surface when compared to a tighter, more conservative tread pattern. Smaller contact patches place the truck’s load on a reduced surface area, thereby resulting in a higher rate of erosion. |
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An example of this is comparing an aggressive rock crawling tire, such as the JConcepts Rupture to a general off-road tire like the MT 2202 from Gmade RC. All things being equal, the Ruptures will wear out much faster than the MT 2202s, but the upside is the vastly superior crawling performance of the Rupture.
It’s possible to squeeze a bit more life out of a tire by rotating and reversing their direction, but technically speaking this is only works for non-directional tires. Some tread patterns are not intended to be reversed, but most drivers ignore these details and reverse the tire. On paper there is a performance loss by doing such, but I’m not sure it can be seen or measured out on the trail. |
The Gmade MT 2202 have impressive tread life.
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All of this said, we consider tread life to be one of the least important aspects of a crawler tire. Unless a tire shreds after a day or two on the trail, it’s going to receive a decent score. We are much more concerned with the amount of traction provided by the rubber compound than how long it lasts.
This category will have a possible of 5/5 points to award.
This category will have a possible of 5/5 points to award.
The Traxxas Trail Canyon crawler tire surprised us with its versatility out on the trail.
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Versatility 5/5
Versatility is the last aspect of a tire we formulate an opinion on, thus placing it last on our list of assessment categories felt correct in the hierarchy. This is mostly due to the time it takes for us to drive over the many different types of terrain over the course of a dozen or more trail sessions. I can’t say that high-level of versatility is something we look to have with a tire, but from time to time we’ve been surprised as to well a particular tire has performed on just about every surface in our trail network. Throughout our testing, we’ve seen some tires excel on one surface but then lack considerable on another. Typically tires with large, chunky tread patterns will perform well on technical rock where the rough, uneven surface offers plenty of places for the lugs to grab hold of. |
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Conversely, on massive chunks of smooth sandstone, some of these chunky tread patterns struggle to find purchase.
On the other end of the spectrum, tires with a tight tread pattern do much better on smooth rock but lack the lug spacing to handle technical rock. As you can see, versatility requires a blend of each, being more like a “middle of the road” tread design rather than something radical or purpose driven. We’ve only awarded five possible points for this section in that while a high level of versatility is desirable, it’s not one of the main guiding factors in tire selection. It’s relevant and interesting, just not that critical. |
Ottsix Racing's USD Sticky is at home in any chunky, loose terrain.
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Working the Losi worm around this tricky corner on Kong Trail.
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Ranking Chart
To bring all this data together, we will be posting ranking chart which contains the results of all tires tested on our website, allowing the reader to quickly compare tires and identify the tire which best suits their needs. At the end of every tire review, there will be a new section added which contains a summary of their performance by category and then a final total score for the tire. These scores are then incorporated into our ranking chart, with the best performing tires placed at the top. As new tires are added, the rankings will be adjusted to reflect their new positioning. We believe this will become a popular section on the website and provide some much-needed comparisons for our readers. |
Our hope is that not only will this information be entertaining, but it will offer some insight as to how tires perform in our terrain as some of the unique traits found in crawling tires which may not be commonly known.
