Cast Gravity Tires Ridden and Reviewed

Who is Cast?

Cast is populated by a group of world-class gravity athletes, engineers, and designers. With input from legends like Greg Minnaar, Danny MacAskill, Fabio Wibmer, Kriss Kyle, Caleb Holonko, Wade Simmons and many more.

Cast’s gravity tires are the Protagonist, for the front wheel, and the Antagonist for the rear. They are intended for Enduro / DH use and were developed with Pirelli Motorsport & Cycling departments, along with feedback from The Cast. They are priced at 130 CAD / 100 USD.

Protagonist Front Specific:

• Size: 29” x 2.4”
• Compound: SmartEVO DH
• Casing: HardWall Enduro Casing or DualWall Enduro / DH Casing
• Weight: HardWall = 1,190 grams claimed, DualWall = 1,268 grams actual (1,310 grams claimed)

Antagonist Rear Specific:

• Size: 29” x 2.4” and 27.5” x 2.4”
• Compound: SmartEVO DH
• Casing: DualWall
• Weight: 29” = 1,276 grams actual (1,300 grams claimed), 27.5” = 1,250 grams claimed

Casing

I measured up the Cast tires relative to an Assegai 29 x 2.5WT and DHR2 29 x 2.4. I felt like that was a similar tread profile and intended use for comparison. All tires were inflated to 23 psi front and 27 psi rear.

The Protagonist’s width across the knobs is 59 mm with a casing width of 58 mm. This is a 4 mm narrower knob width and a 2 mm narrower casing width than the Assegai from my measurements. The Antagonist’s width across the knobs is 61 mm with a casing width of 58 mm. This is 1 mm wider in the knobs and the same casing width as the DHR2 by my measurement.

The casing feels sturdy and relatively supple. I’d say it’s somewhere between a Maxxis DH casing and a Schwalbe DH casing.

Rubber Compound

I have a durometer tester, and I took measurements before using them.

• Side knob durometer 50 A (New)
• Center knob durometer 54A Protagonist and 52A Antagonist (New)

While these do measure a step firmer than a Maxxis MaxxGrip or Schwalbe Ultra Soft, this was intentional. Cast and Pirelli chose to go with a single compound all the way through the knob, so as the tire wears, there is good traction through the tire’s life. According to Cast, Pirelli wasn’t focused on making the softest possible tires. Pirelli also looks at chemical adhesion and other aspects of tire traction beyond just durometer.

Tread Profile

Cast tires look like they take inspiration from some classic, well-respected tires. This makes sense. If I were to release a new enduro / DH tire combination, that seems like a pretty good place to start.

I like that it’s clear these are intended to be used as a pair. The side knobs on both tires look quite similar, with a bit more support on the rear side knob. This should help keep the front-to-rear cornering balance consistent. Both tires have ample transition knobs, so there should be consistent grip as the tire transitions from braking to cornering.

The Protagonist front tire looks to have a bit more aggressive center profile that should provide better penetration into the trail, and stronger braking traction. The Antagonist looks like it should roll faster, while still offering great braking traction.

Impressions

Installing the tires on my We Are One Union rims was easy. The bead sizing was perfect, making installation and inflation with a booster floor pump easy peasy.

Most of the review period I’ve ridden these tires has been wet. That is, until the last month of dry weather, so thankfully, I’ve been able to evaluate the Cast tires through a variety of conditions and trail types. For an aggressive tread profile, these do seem to roll well, but I wouldn’t call them particularly fast either. A highly scientific rolling speed test relative to friends, and it seems like these Cast tires are not significantly faster or slower than the usual high-grip suspects on our enduro bikes.

The slightly harder rubber compound means that the Cast tires might not have the peak traction of a Schwalbe Ultra Soft or Maxxis MaxxGrip tire combination, particularly on slick roots and rock. To be clear, the traction isn’t poor; it’s just a smidge less than I’ve come to expect. Traction in wet dirt, however, is excellent. I like how supportive the knobs are. Heavier and more aggressive riders might notice less knob squirm under heavy braking and cornering. This seems to provide a consistent result that I quite like. Also related to the supportive structure of the tires, I found exceeding the limit of traction quite progressive and predictable. While the traction peak might be a touch lower, riding at the limit was predictable and consistent.

Durability-wise, I had no issues with the Cast Tires during the review period. The casings seem durable, and tread wear appears to be gradual.

For a first attempt, I’m impressed with the Cast Gravity Tires. In the wet winter riding conditions in Squamish, the Cast Gravity Tires felt a bit firmer in compound than the Maxxis and Schwalbe grip monsters. Cast’s Gravity Tires started to shine once the trails dried out a bit, and temps rose. The Protagonist and Antagonist are supportive, efficient, grippy, and fast tires. I think these would be an excellent summer all-rounder. Given the graceful wear, these might be an excellent choice on an ebike if you’re getting in a ton of mileage. The casings seem solid, and while the options are limited, I think they’re the options you want. These Cast tires are a well-thought-out product. Pricing-wise, these are similarly priced to other premium options, and I personally like that I’m supporting something based out of North Vancouver. I’m looking forward to seeing what this group of people comes up with next.

Cast Gravity Tires