The TIME ATAC XC 2 [paid link] pedals and the Shimano PD-M520 are two of the most commonly compared clipless pedal systems among road and cross-country riders. Both models cater to cyclists who value efficient power transfer, reliable engagement, and long-term durability. However, their underlying design philosophies, engagement mechanics, and riding characteristics differ significantly. This guide provides an in-depth technical comparison to help riders make an informed choice between the TIME ATAC XC 2 [paid link] and Shimano PD-M520 pedals.
Design and Build Quality
The TIME ATAC XC 2 pedals use a composite body construction with a steel axle, resulting in a lightweight yet robust platform suited for both road and off-road conditions. The design emphasizes self-cleaning capability through its open, dual-arch engagement mechanism that allows mud and debris to clear easily.
By contrast, the Shimano PD-M520 features a compact aluminum body with a sealed bearing cartridge and a dual-sided SPD mechanism. While heavier, its enclosed structure offers excellent resistance to impacts and wear from rocky or muddy environments. However, it tends to accumulate debris more readily than the ATAC system, requiring more frequent maintenance.
Engagement Mechanism and Float Feel
The defining characteristic of the TIME ATAC XC 2 system is its Automatic Tension Adjustment Concept (ATAC), which delivers a natural feel through a generous angular float of 13° and a lateral float of up to 6 mm. This design significantly reduces knee strain during long rides, making it a top choice for riders prioritizing joint comfort and biomechanical freedom.
The Shimano PD-M520, on the other hand, employs a fixed-tension spring system with adjustable release settings. While it allows riders to fine-tune the tension to their preference, it offers less float and a more mechanical release feel. The SPD interface provides a firmer, more locked-in sensation that suits riders who prefer minimal lateral movement during intense efforts.
In practice, the ATAC XC 2’s engagement is quicker and more forgiving in dirty or wet conditions, while the M520 provides a tighter and more precise interface for those seeking a connected pedaling experience.
Cleat Design and Compatibility
TIME’s ATAC cleats [paid link] are brass-based and feature a self-cleaning, mud-shedding design that complements the pedal’s open structure. They offer two release angle options—13° or 17°, depending on how the cleats are mounted. This modularity enables riders to customize release feel without changing hardware.
Shimano’s SPD cleats are made of steel and designed for consistent engagement. They provide a single release option of approximately 13°, with a limited float range. SPD cleats are widely compatible across multiple Shimano pedal models, offering easy replacement availability. However, they can wear down faster when walked on compared to TIME’s recessed cleat shape, which provides better off-bike traction.
Bearing System and Maintenance Requirements
The TIME ATAC XC 2 pedals utilize a steel axle with a bushing and cartridge bearing combination, which requires minimal maintenance under normal use. The pedal body’s open structure naturally expels mud and water, extending bearing life. Regular cleaning and occasional lubrication of the axle assembly ensure smooth rotation and long-term reliability.
In contrast, the Shimano PD-M520 employs sealed cartridge bearings that provide excellent durability in harsh conditions. However, due to its more enclosed body design, grime can accumulate over time, necessitating more frequent servicing to prevent bearing wear or stiffness. The advantage of the M520’s system lies in its serviceability—bearing kits and seals are widely available, making overhaul straightforward.
Weight and Efficiency
When comparing weight, the TIME ATAC XC 2 pedals stand out at approximately 151 grams per pedal, giving them a noticeable advantage for riders concerned with minimizing rotational mass. Their composite material contributes to a lighter build without compromising rigidity.
The Shimano PD-M520 weighs about 185 grams per pedal, a marginal increase that translates to slightly slower engagement in acceleration scenarios. However, the difference in efficiency is subtle and largely dependent on rider preference and terrain type.
The ATAC XC 2 provides a smoother power transfer for long climbs and endurance rides, while the M520’s firm engagement appeals to sprint-oriented riders seeking a more direct pedal feel.
Performance in Adverse Conditions
The TIME ATAC XC 2’s self-cleaning system offers superior performance in muddy or snowy conditions. Its open architecture ensures consistent clipping in and out, even when debris is present. This makes it particularly suitable for cyclocross and gravel riders who frequently encounter variable terrain.
Conversely, the Shimano PD-M520’s SPD system can become obstructed in muddy environments, occasionally preventing full engagement. Riders using the M520 in such conditions must routinely clean the pedal and cleat interface to maintain optimal function. Nevertheless, it performs reliably in dry or moderate-weather scenarios, providing stable engagement and release.
Rider Feel and Biomechanics
Riders switching between these two systems will immediately notice the difference in float and feel. The TIME ATAC XC 2 allows more natural foot movement, accommodating slight variations in pedaling form without causing strain. This flexibility benefits riders recovering from injuries or those prone to knee discomfort.
The Shimano PD-M520 delivers a more locked-in sensation, ideal for riders who demand consistent alignment and prefer a rigid pedaling platform. However, the reduced float can feel restrictive to those accustomed to freer movement, especially during long-distance efforts.
Durability and Longevity
Both pedals are engineered for long service life, but their wear characteristics differ. The TIME ATAC XC 2’s composite body resists corrosion effectively, while the brass cleats gradually wear to preserve the pedal interface. Shimano’s all-metal construction ensures durability against impacts but may suffer cosmetic wear from repeated clipping and debris exposure.
Under heavy usage, the ATAC XC 2 typically requires less frequent cleat replacement, while the M520 may need periodic attention to maintain smooth release function. Riders focused on longevity with minimal upkeep often find the TIME system more forgiving in the long term.
Which Pedal Should You Choose?
Cyclists who value comfort, easy engagement, and low maintenance will benefit from the TIME ATAC XC 2. Its lightweight design, natural float, and excellent self-cleaning ability make it ideal for endurance riders, cyclocross racers, and those seeking biomechanical efficiency.
In contrast, the Shimano PD-M520 is best suited for budget-conscious riders or those who prefer a tighter, more controlled feel. It provides reliable performance and serviceability at a lower cost, albeit with slightly higher maintenance needs.
Ultimately, the choice depends on the rider’s priorities—comfort and self-cleaning performance favor the TIME ATAC XC 2, while rigidity and adjustability favor the Shimano PD-M520.
Conclusion
The TIME ATAC XC 2 pedals stand out for their superior mud clearance, generous float, and ease of maintenance, offering a forgiving and efficient ride experience. Meanwhile, the Shimano PD-M520 remains a dependable workhorse, known for its adjustability and proven SPD interface. Riders seeking natural motion and long-term comfort should opt for the ATAC XC 2, whereas those preferring a firmer, performance-oriented setup may lean toward the PD-M520.