Skateboard Bearing Guide

1. Bearing anatomy

A skateboard bearing is a standard 608-size ball bearing: 8mm inner diameter (fits skateboard axles), 22mm outer diameter (fits standard wheel cores), 7mm width. All skateboard bearings from all brands are this same size — they're interchangeable across trucks and wheels.

Inside: an inner race (fits the axle), an outer race (presses into the wheel), 7 or 8 steel or ceramic balls, a cage (holds balls in position), and a lubricant. The shield or seal (one or two per bearing) covers the ball area to keep out debris and retain lubricant.

2. ABEC ratings — what they really mean

ABEC stands for Annular Bearing Engineering Committee. The rating (1, 3, 5, 7, 9) describes dimensional precision — how tightly the manufactured dimensions match the specification. Higher ABEC = tighter tolerances = potentially smoother running in precision applications.

The skateboard industry marketing around ABEC ratings is largely misleading. Here's why:

• ABEC precision benefits are meaningful at very high RPM (industrial machinery, turbines). Skateboard wheels spin at much lower RPM — the precision difference between ABEC 5 and ABEC 9 is undetectable at skating speeds.
• ABEC standards don't measure impact resistance, which is what bearings take most of in skating. A technically high-ABEC bearing that isn't impact-rated may fail faster under skating loads than a lower-ABEC bearing with better steel.
• Many premium skate bearings (Bones Reds, Bronson) use their own internal ratings that don't directly correspond to ABEC grades — which is valid, since ABEC doesn't measure what matters in skating.

Practical takeaway: Don't buy bearings based on ABEC number alone. Brand quality, steel grade, lubrication, and bearing cleanliness matter far more. ABEC 5 from a reputable skate brand will outperform ABEC 9 from an unknown manufacturer.

3. Steel vs ceramic bearings

The honest verdict: ceramic bearings are a genuine upgrade for downhill longboarders who spend time at 30–50 mph where heat buildup and sustained rolling resistance actually matter. For everyone else — street, park, cruising — the premium is hard to justify. Well-maintained steel bearings spin fast, last long, and cost a fraction of ceramics.

If you're curious about ceramic but don't want to spend $100+, some brands offer "hybrid" bearings with ceramic balls in steel races — typically $40–$60 for 8, a middle ground that provides some corrosion resistance benefit at a lower price.

4. Shields vs seals

The cover over the bearing's ball cavity protects the internals from dirt and retains lubricant.

• Metal shields (removable) — a thin metal disc that snaps in. Can be removed with a pin or safety pin for cleaning and re-lubing. Most skate bearings use removable metal shields on one or both sides. This is the most practical design for skaters who maintain their bearings.
• Rubber seals (non-removable or difficult to remove) — better contaminant protection but harder to service. Common on "sealed" bearings marketed for outdoor/wet use. Some sealed bearings can be opened with care; others are meant to be replaced when spent.

For most skaters who clean their bearings: get bearings with removable metal shields. If you ride in the rain regularly or won't clean bearings, sealed rubber-shield bearings offer better protection but you'll replace rather than clean them.

5. Lubrication

Bearings come pre-lubed from the factory. Over time, lube degrades, gets contaminated, or washes out. The right lubricant affects both speed and longevity.

Use 1–2 drops of oil per bearing after cleaning — more doesn't help and creates drag. The most common over-lubrication mistake is applying too much oil, which attracts grit rather than repelling it.

Never use WD-40 as bearing lubricant. It's a water displacer and solvent, not a lubricant. It will clean bearings but also strip all protection, causing them to corrode and fail rapidly.

6. Brand guide by budget

Recommendation for most skaters: Bones Reds or Bones Super Reds. They hit the sweet spot of quality, longevity, serviceability, and cost. Both use removable metal shields for easy maintenance. If you skate frequently and maintain your bearings, Super Reds are worth the modest premium over standard Reds.

7. Replace vs clean — when to do each

Clean when:

• The bearing spins less freely than it used to but isn't making noise
• Bearings got wet (immediately — water flushes lube but doesn't damage the races)
• It's been 1–3 months since last maintenance
• You can see visible grit or debris on the bearing surface

Replace when:

• Bearing makes grinding, clicking, or rattling noise after cleaning
• Bearing wobbles on the axle (pitted or cracked inner race)
• The wheel doesn't spin freely even on a clean, lubed bearing
• Shield or cage is visibly cracked or deformed
• Bearing has been dry-run (riding with no lube) — steel-on-steel contact without lube causes rapid irreversible damage

When in doubt: clean first. A clean and properly lubed bearing often performs as well as a new one. Only replace if cleaning doesn't fix the problem. Given Bones Reds cost $20 for 8, there's no reason to ride failed bearings — they cause unnecessary wheel resistance and can seize unexpectedly.

See How to Clean Skateboard Bearings for the full step-by-step process, and Skateboard Maintenance Guide for the full maintenance schedule.

8. Installation

Each wheel takes two bearings — one on each side of the wheel core. The standard installation process:

1. Press the first bearing onto the axle (shield side out, so the open face is toward the wheel core).
2. Press the wheel down onto the bearing until it seats fully. Use the axle as a press — hold the truck and press the wheel down firmly.
3. Flip the wheel over and press the second bearing the same way.
4. If present, install a bearing spacer between the two bearings inside the wheel. Spacers aren't universal but are recommended for wheels that accommodate them — they keep the bearings aligned and reduce axle flex stress.
5. Install speed washers (thin metal washers) on the axle on both sides of the wheel before threading the axle nut.
6. Thread the axle nut finger-tight, then tighten until the wheel has minimal side play — it should spin freely but not wobble.

See How to Change Skateboard Wheels for the complete process including bearing removal and transfer.