Bearings Buying Guide - SkatePro

If you're pondering which bearings to choose, you've come to the right place! This guide will illuminate the crucial terminology and facts regarding bearings and direct you toward the most suitable options tailored to your skating or riding style.

1. An Overview of Bearings

A single wheel requires two bearings to rotate smoothly around the axle. The quality and characteristics of these bearings can significantly affect your skating or riding experience. To extend their lifespan, it's vital to keep bearings away from sand, water, and moist environments. Regular cleaning and lubrication are key strategies to enhance both their durability and performance. Check out our instructions on how to clean your bearings learn more.

Additionally, a spacer is necessary to fill the gap between the bearings, ensuring they do not become damaged and rotate seamlessly when the axles are secured. The required spacer size varies according to the axle size used.

8 mm spacer

6 mm spacer

The overall quality of the bearings is determined by several factors, including:

• Material
• Precision (ABEC ratings)
• Lubrication type
• Sealed versus open designs (Removable Shields)

To help you choose the best bearings for your needs:

• If you primarily skate outdoors, we endorse sealed bearings filled with grease, as they are more resistant to dirt and dust and typically require minimal maintenance.
• If your skating environment is indoors, consider open bearings that offer rapid rotation and effortless cleaning.
• If speed and extended distances are your aim, high-precision bearings with oil lubrication are ideal. They excel in speed and maintain cleanliness but are vulnerable to rapid wear from dirt.

2. Installing Bearings

Bearings can usually be pressed into place using your thumbs. Properly aligned bearings will sit flush with the wheel core/hub. Misalignment will lead to damage during use. If you are using a wheel with a metal core, installation can be tricky; in such cases, a rubber mallet or a flat piece of wood can be employed. Never use a metal hammer, as this will damage the bearing and void any warranty.

Alternatively, lubrication can assist in seat the bearing. However, any excess lubricant must be carefully wiped away afterward.

3. In-Depth Look at Bearings

Material Considerations

The composition of bearings plays a vital role in their performance and longevity. While most bearings are constructed from steel, lower-quality options often use pressed sheet metal or hardened carbon steel, which are less desirable for longevity. Quality bearings utilize advanced materials such as chrome, titanium, or Swiss steel. Some high-performance applications might employ ceramic bearings (often favored in speed skating), which resist rust and exhibit higher durability than steel counterparts.

Typically, you can expect a direct correlation between price and quality, with established brands often producing reliable, durable products.

Precision and the ABEC Rating

Bearings are classified based on the ABEC standard, which assesses a bearing’s ability to handle applied forces. Higher ABEC ratings entail improved precision, efficiency, and speed potential but do not necessarily dictate faster rotation speeds. Importantly, the ABEC rating overlooks other essential factors, such as the quality of the spacers and wheels, as well as the materials used. All bearings' precision will degrade over time with use.

It is crucial to recognize that some brands do not utilize the ABEC grading system (like Bones) and that alternative bearing rating systems exist. ABEC stands for Annular Bearing Engineering Committee.

Lubrication Methods

Bearings may be lubricated with either oil or grease. A bearing should never be devoid of lubrication as this can lead to overheating, loss of speed, or complete failure.

• Oil: Provides high-speed capabilities due to lower resistance and requires routine maintenance as it can degrade quicker.
• Grease: Offers better resistance to dirt and moisture, needs little maintenance, but can create higher friction resulting in lower speeds.

Important Note: Water can wash away all lubrication. If this occurs and subsequently evaporates, the bearings may overheat, potentially leading to melting and rattle sounds upon the next use, necessitating replacement. Occasionally, if the bearings have not been used in between, they can be revived through proper cleaning and oiling before use.

Seals and Shields

To keep dirt, sand, and moisture out of the bearings, seals or shields are commonly installed on one or both sides of the bearing.

• A Shield is typically a metal guard attached to the outer ring, designed to create minimal friction and thus enhancing rotation speed but offers less protection against moisture and dirt.
• A Seal, usually made from steel-enforced rubber, contacts the inner ring for better protection with minimal maintenance, but might introduce more friction leading to slightly reduced speed.

4. Understanding ABEC Ratings and Precision

The ABEC scale accounts for various factors, such as the eccentricity of the inner ring's track. Below is the maximum allowable eccentricity for each grade.

In essence, a higher ABEC rating indicates reduced variability in the bearing components, facilitating better power transfer to the wheel.

It’s essential to note that ABEC and ILQ are not directly comparable since ILQ is a brand designation while ABEC represents a standard.

Bearings rated by the ABEC scale measure production accuracy rather than durability or performance under load. Manufacturers like Twincam, which produces ILQ bearings, evaluates their bearings on a scale similar to ABEC but uses a different design, often featuring six balls instead of the seven found in ABEC-rated bearings.

For clarity, ILQ does not equate to a standard comparable to ABEC ratings and should be regarded as a non-rated option from a specialized inline bearing manufacturer, not suited for industrial machinery.

Bones bearings are specially crafted for skating and do not conform to ABEC criteria.

The following terminology relates to bearings and their shields; the specifications are typically printed on the bearing alongside its dimensions, such as: 608ZZ.

608

• Standard bearing
• 22 mm outer diameter
• 7 mm width
• 8 mm inside diameter

688

• Mini/Micro bearing
• 16 mm outer diameter
• 5 mm width
• 8 mm inside diameter

Z

• Shield, featuring 1 metal shield
• Open at the opposite end for simpler maintenance (always install with the open side facing the inner wheel)

ZZ

• Shield with 2 metal shields
• Shields secured with a small C-ring, which must be removed to access for maintenance.

2RS/RS/RZ

• Seal, equipped with 2 steel-armed rubber seals
• Seals are mounted without C-rings, allowing for careful removal with a needle for maintenance.

BRS

• Seal, comprising 2 steel-armed rubber seals (contact-free)
• No C-rings are employed, providing additional protection against water infiltration.