Maxxis Aspen ST 29×2.25

RUBBER COMPOUNDS

The tread compound is the most important part of a tire. By adjusting rubber ingredients, engineers can make two identical-looking tires perform very differently. Below are Maxxis compounds and their key features:

Single Compound: One compound throughout the tread, optimized for durability and balanced performance.

Dual Compound: Two compounds in the tread for lower rolling resistance and improved cornering grip (MTB tires).

Triple Compound: Three compounds arranged for uncompromising race performance.

Single and Dual Compound tires are durable, reliable, versatile, and more affordable. Their slightly harder rubber also performs well in freezing winter conditions.

MaxxSpeed (3C MaxxSpeed)

A high-silica XC race compound that reduces rolling resistance while improving wet grip. Designed for maximum speed and efficiency.

3C MaxxTerra

Harder center knobs keep rolling resistance low while maintaining good durability. Ideal for versatile trail riding in both dry and wet conditions.

3C MaxxGrip

Maxxis’ grippiest and slowest-rebound compound, used by World Cup Downhill and Enduro World Series athletes. Features a thicker outer layer of soft, tacky rubber for maximum traction. Designed for racing in temperatures above +4°C (39°F). When nothing else grips, MaxxGrip does.

Note: The soft outer layers of 3C tires harden in cold weather, reducing grip and performance and possibly causing surface cracking. For winter riding, harder Dual Compound tires are recommended.

BASIC TIRE CONSTRUCTION
Bead

The bead secures the tire to the rim.

Wire Bead: Rigid steel bead for maximum durability and lower cost.

Foldable Bead: Lightweight aramid (Kevlar®-type) fibers. Easier to transport, better terrain conformity, and improved rolling feel.

Casing

Single-Ply (Single Wall): One nylon layer from bead to bead. Lightweight and terrain-adaptive.

Dual-Ply (Double Wall): Two layers for added protection and sidewall damping. Designed for Enduro, E-bike, and Downhill use (DoubleDown and Downhill tires).

TUBELESS READY (TR)

Maxxis Tubeless Ready (TR) tires offer better grip, lower rolling resistance, and fewer flats when used with tubeless sealant (e.g., Stan’s). Lower pressures improve traction and control. Look for the “TR” marking on the sidewall.

Installation: Must be used with tubeless-compatible rims and sealant to maintain air pressure and seal small pores. Check and refill sealant regularly as it dries over time.

Important: Use sealant only in tires marked “TR.” Using it in other Maxxis models voids the warranty.

PUNCTURE PROTECTION & CASING TECHNOLOGY
TPI (Threads Per Inch)

The number of threads per square inch in one casing layer.

Lower TPI (e.g., 60): Better cut, puncture, and abrasion resistance improved damping heavier weight.

Higher TPI (e.g., 120): Lighter, more supple, smoother ride feel, better terrain conformity. However, it is more fragile and can feel more “bouncy” at high speeds compared to 60 TPI.

Maxxis TPI ratings refer to threads per inch in a single casing layer (unlike some competitors).

Silkworm

An exclusive material integrated under the tread to increase puncture and cut resistance.

ZK

A next-generation puncture protection material—lighter, more flexible, and stronger than older materials like K2. Typically placed under the tread center in road tires.

EXO Protection

A lightweight, flexible, densely woven sidewall protection against cuts, punctures, and abrasion. Ideal for gravel, XC, and trail riding.

EXO+

Mid-level protection for trail riding and light E-bike use. Built on a durable 60 TPI casing with EXO sidewall protection plus a butyl insert around the bead. Protects against rock/root damage, pinch flats, and rim impacts.

DoubleDown (DD)

Designed for bike park, enduro racing, and E-bikes. Two lightweight 120 TPI casing layers combined with a butyl sidewall insert create a highly durable tire with more trail feel than a full Downhill casing. Slightly lighter than Downhill versions the main difference is ride feel.

Downhill (DH)

Built for extreme gravity use: downhill, bike park, freeride, and heavy E-bikes. Features two layers of durable 60 TPI casing plus a large butyl insert from bead to sidewall for maximum impact protection, rim protection, and added sidewall stability.