{"id":241141,"date":"2026-04-29T15:00:00","date_gmt":"2026-04-29T15:00:00","guid":{"rendered":"https:\/\/sports.runfyers.com\/index.php\/2026\/04\/29\/ethirteen-expands-the-grappler-tire-platform-adding-a-radial-casing\/"},"modified":"2026-04-29T15:00:00","modified_gmt":"2026-04-29T15:00:00","slug":"ethirteen-expands-the-grappler-tire-platform-adding-a-radial-casing","status":"publish","type":"post","link":"https:\/\/sports.runfyers.com\/index.php\/2026\/04\/29\/ethirteen-expands-the-grappler-tire-platform-adding-a-radial-casing\/","title":{"rendered":"e*thirteen Expands the Grappler Tire Platform, Adding a Radial Casing"},"content":{"rendered":"

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There is some more big news regarding e*thirteen\u2019s new mountain bike tires. And, no, they aren\u2019t 32\u201d. <\/p>\n

This announcement concerns the other hot topic in mountain bike tire development: radial rubber<\/a>. The new radial casing comes on the Grappler tire platform, but e*thirteen didn\u2019t stop there. Today, e*thirteen announces the expansion of the Grappler tire to include not only radial options but also new rubber compounds, treads, casings, and rear-specific tires.<\/p>\n

The New e*thirteen Grappler <\/h2>\n
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\"E13<\/a><\/figure>\n<\/figure>\n

The Grappler<\/a> has been around for a few years now. First introduced in 2022, e*thirteen designed the tire with one thing in mind: gravity. The tread was aggressive, with tall shoulder knobs and a 3-2-3 tread pattern for the center lugs.<\/p>\n

Clearly, the Grappler was aimed at enduro and DH riders.<\/p>\n

And those were exactly the casing options. e*thirteen offered the Grappler in an Enduro or DH casing, with the choice of their MoPo or Endurance rubber. <\/p>\n

\n
\"E13<\/a><\/figure>\n
\"E13<\/a><\/figure>\n<\/figure>\n

Size was the only option left, with the choice of 29\u201d or 27.5\u201d, with both diameters coming in a 2.5\u201d width.<\/p>\n

Building off of that design (literally, it looks like they carried over the same tread pattern), e*thirteen significantly expands the Grappler tire platform. What was one Grappler is now three. <\/p>\n

Before jumping into the new tires, let\u2019s look at the new features seen across (most) the Grappler platform.<\/p>\n

Casing and Compounds<\/h2>\n

It\u2019s why you clicked. You saw \u201cradial casing\u201d and needed to see the new offering. Yes, one of the new casings on the e*thirteen Grappler tire is radial. In fact, e*thirteen provides a whole new naming structure for tire casings, moving away from casing names matching intended riding use.<\/p>\n

Casings<\/h3>\n
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\"E13<\/a><\/figure>\n<\/figure>\n

Flux GR Radial.<\/strong> This is, well, the radial casing, and the most aggressive tire in terms of traction and support. e*thirteen uses \u201csuper-stiff Dual Apex Sidewall Inserts\u201d in the Flux GR Radial casing. Not only does the casing feature extra bead support to prevent pinch flats, but an overall beefy construction also creates firm sidewalls. <\/p>\n

Extra material increases lateral stability. The big takeaway here is that e*thirteen says you can run normal tire pressures. For comparison, when I use Schwalbe radial tires, I typically run 4-6 PSI higher than with non-radial tires. While e*thirteen recommends a slight increase for significantly rocky trails, they claim tire pressure should remain relatively normal.<\/p>\n

e*thirteen also claims a significant increase in traction. Compared to non-radials, the new Flux GR Radial casing tires have a (claimed) 30% larger contact patch. e*thirteen also claims increased comfort, as the radial casing acts as extra suspension for the bike.<\/p>\n

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\"e*thirteen<\/a><\/figure>\n
\"e*thirteen<\/a><\/figure>
Radial casing on the right<\/figcaption><\/figure>\n

Stepping down from radial is the Flux GR<\/strong> casing. While this casing isn\u2019t radial and doesn\u2019t see the same Dual Apex Sidewall Inserts, it does feature e*thirteen\u2019s GR Apex inserts. Like the Dual Apex inserts, the GR Apex inserts beef up the sidewalls, increasing lateral stability and overall durability.<\/p>\n

Both the Flux GR Radial and Flux GR casings also feature two-ply, 72 TPI construction and Armor Weave sidewall protection. <\/p>\n

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\"new<\/a><\/figure>\n<\/figure>\n

Stepping down from there, e*thirteen offers a third casing: Flux AM<\/strong>. Tires with Flux AM casing feature two-ply construction with 90 TPI. While this casing doesn\u2019t have either Apex inserts, it does have the Armor Weave sidewall protection.<\/p>\n

For the Flux AM, e*thirteen wanted lighter weight and faster rolling.<\/p>\n

Compounds<\/h3>\n
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\"e*thirteens<\/a><\/figure>\n<\/figure>\n

Along with the three casing options, e*thirteen offers two rubber compound options for the new Grappler tires. <\/p>\n

First is their motion potion; the MoPo<\/strong> rubber, e*thirteen\u2019s softest and grippiest option. MoPo is constructed with ultra-soft 42a rubber, which is now featured throughout the entire tread. e*thirteen claims this reduces tread rebound and enhances vibration damping. <\/p>\n

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\"Momentum<\/a><\/figure>\n<\/figure>\n

The other compound option (no more \u201cEndurance\u201d) will be e*thirteen\u2019s Momentum<\/strong> rubber. Momentum is a dual-compound design, with a firmer 50a rubber in the center and the soft 42a rubber at the shoulders. e*thirteen says Momentum provides great longevity without sacrificing performance, and is an ideal choice for rear tires and eMTBs.<\/p>\n

The Expanded Grappler Lineup<\/h2>\n
\n
\"Three<\/a><\/figure>\n<\/figure>\n

So now e*thirteen\u2019s Grappler is actually a family of three tires. Well, three tread patterns. Well, sort of two\u2026<\/p>\n

In the press material, they referred to the range as \u201csimplified,\u201d which I think is quite a stretch. Just in case I miss anything, I will include a chart that helps line up all the new options. Now, here goes my attempt to explain the new tire offerings.<\/p>\n

3 New Tires<\/h3>\n
\n
\"Grappler<\/a><\/figure>\n<\/figure>\n

First, there is the tire that will remain the Grappler<\/strong>. This is the aforementioned tire that appears to use the same (or very similar) 3-2-3 tread pattern as its predecessor. It is e*thirteen\u2019s gravity cornerstone (for tires, at least) and offers the most options in the lineup.<\/p>\n

\n
\"e13<\/a><\/figure>\n
\"Grappler<\/a><\/figure>\n<\/figure>\n

The Grappler\u2019s intended use stretches from trail and all-mountain to DH and eMTB. The use will depend on the casing chosen, which the Grappler provides all three Flux casing options. You also have the choice of MoPo or Momentum rubber compounds, making the tire ideal for the front or the rear. e*thirteen says it does best in loose, wet, and\/or technical terrain.<\/p>\n

Moving on from the Grappler is the Grappler RS<\/strong>. I\u2019m assuming here that \u201cRS\u201d means \u201cRear Specific\u201d because e*thirteen says this is a rear-specific tire. What makes it a rear tire?<\/p>\n

\n
\"e13<\/a><\/figure>\n
\"Grappler<\/a><\/figure>\n<\/figure>\n

e*thirteen created the Grappler RS with a \u201crear-optimized 2-2-2\u201d tread pattern, adding tall and steeply ramped center knobs. This not only improves braking traction but also increases rolling speed. Oh, and the Grappler RS only comes in a 27.5\u201d.<\/p>\n

With the Grappler RS, the only casing options are the Flux GR Radial and Flux GR. The rear tire is available in both rubber compounds and is intended for enduro, DH, and eMTBs.<\/p>\n

Lastly, we have the Grappler TR<\/strong>. As far as tread goes, it looks like the Grappler RS, but e*thirteen says it has a lower profile. But that means faster rolling and lightweight. <\/p>\n

\n
\"e13<\/a><\/figure>\n
\"Grappler<\/a><\/figure>\n<\/figure>\n

The Grappler TR also sees the fewest choice options. While the tire was intended for front or rear and is available in 29\u201d or 27.5\u201d, that is where the choices stop. No radial casing, just the Flux AM casing, and only the Momentum Compound rubber. <\/p>\n

Pricing and Details<\/h2>\n

In the press material, e*thirteen also used the term \u201caffordable.\u201d That, I can agree with. The range starts at $60 and tops out at $80. <\/p>\n

Not bad considering some tires are double that.<\/p>\n

If you didn\u2019t see them in the chart above, here are some weights and prices for the new lineup:<\/p>\n

Grappler<\/strong><\/p>\n