The right roller skate bearings must fit both your axles and your wheels. Start with those measurements, then compare construction and maintenance requirements. A familiar brand name or a high ABEC number cannot confirm that a bearing fits your setup.
This guide explains the main sizes used in quad skating and what to check before ordering. For servicing an existing set, go to our bearing cleaning and installation guide.
Match the axle and wheel first
The bore is the hole through the middle of the bearing. It must match the axle. The outer diameter must match the bearing seat in the wheel. Standard and mini bearings can have the same bore while having different outer diameters.
| Bearing | Bore | Outer diameter | Setup to check |
|---|---|---|---|
| 608 | 8 mm | 22 mm | 8 mm axle with a standard wheel bearing seat |
| 627 | 7 mm | 22 mm | 7 mm axle with a standard wheel bearing seat |
| 688 | 8 mm | 16 mm | 8 mm axle with a compatible mini bearing seat |
| Bont 167 | 7 mm | 16 mm | 7 mm axle with a compatible mini bearing seat |
Read the wheel and plate specifications as well as the bearing label. Some mini bearings can be used in a larger bearing seat with a compatible adapter. An adapter for the outside of a bearing does not change its bore or turn a 7 mm bearing into an 8 mm bearing. Our mini bearing guide explains these setups in more detail.
What ABEC ratings tell you
ABEC classifies manufacturing tolerances. It does not describe every factor that affects a bearing in a skate, such as lubrication, sealing, contamination resistance or performance under skating loads. A higher printed number alone cannot tell you which bearing will roll better in your skating conditions.
Check the complete specification, fit and service requirements. If a seller gives only an ABEC number, ask for the bearing dimensions and construction before ordering.
Compare materials and the complete bearing
Steel and ceramic options appear in the Bont bearing collection. Compare the actual product specification rather than assuming that a material name guarantees a particular result. Check which components use the stated material, the shielding, supplied lubricant and recommended care.
For example, the Bont PRO 627 is listed with steel balls, a 7 mm bore, a 22 mm outer diameter and a 7 mm width. These details identify a setup it can fit; they are more useful for compatibility than a general claim about speed.
Choose bearings you can maintain
Before buying, check whether the shields are removable, how the bearings should be cleaned and which lubricant is specified. Use the manufacturer instructions for that model. Routine care requirements matter if you skate often or in dusty conditions.
Bearings should be clean, correctly lubricated and seated properly in the wheel. If an existing bearing feels rough, inspect and service it before assuming that you need a more expensive model.
How many bearings do roller skates need?
A conventional pair of four-wheel quad skates uses 16 bearings: two per wheel across eight wheels. Check whether a product is sold as individual bearings, a pack for one skate or a full set. Also check whether adapters and spacers are included or purchased separately.
Can you use skateboard bearings on roller skates?
Some skateboard bearings are 608 size and can fit quad setups that require that size. Confirm the actual dimensions, axle bore, wheel bearing seat and any spacer requirements first. They will not fit a 7 mm axle correctly simply because they are sold for skating.
Check your order
- Confirm your axle diameter and wheel bearing seat.
- Match the bearing size and any required adapter.
- Check the pack quantity and included components.
- Read the cleaning and lubrication instructions.
Browse Bont roller skate bearings with your wheel and plate specifications to hand. If you are unsure about compatibility, contact Bont before ordering.
Alexander Bont’s bearing experience
I have been testing inline and roller skate bearings for over 30 years. As the Director of Bont Skates, it is my responsibility to make sure our professional skating team is on the very best bearings in the world. I have no agreement with any single bearing company and I source skate bearings from a number of different manufacturers in different countries. Each week I am approached by no less than five bearing manufacturers asking me to test their skate bearings for Bont Skates. Some I test, some I don’t, it depends if they sound like they are making quality bearings or not. Over the years I have tested hundreds of different brands of skate bearings.