Brake rotors: which size, Center Lock or 6-bolt?
Updated October 8, 2026 · Fahrradwerkstatt Avelo, Hamburg
A brake rotor must match your hub (Center Lock or 6-bolt), your brake (the diameter the caliper is mounted for, and rotor thickness) and your riding. Bigger rotors brake harder and run cooler: typically 140–160 mm on road bikes, 180–203 mm on mountain bikes and up to 220 mm on e-MTBs.
Center Lock or 6-bolt?
That depends only on your hub. Center Lock (a Shimano standard) slides onto splines and is held by a lockring; 6-bolt (IS) is fixed with six bolts. A 6-bolt rotor can go on a Center Lock hub with an adapter, but not the other way round.
Which diameter?
The caliper is mounted for one diameter. Moving to a bigger rotor needs the matching caliper adapter and must stay within what your fork and frame allow.
| Riding | Common sizes |
|---|---|
| Road, gravel | 140 mm, 160 mm |
| Cross-country, trail | 160 mm, 180 mm |
| Enduro, downhill | 200 mm, 203 mm |
| E-MTB | 203 mm, 220 mm |
Thickness and construction
Most rotors are 1.8 mm thick; some brands (Magura, for example) use 2.0 mm. Follow your caliper maker's specification. Two-piece or floating rotors (aluminium carrier, steel braking track) are lighter and warp less under heat than one-piece rotors.
Frequently asked questions
Can I run a Shimano rotor with a SRAM brake?
Usually yes, if diameter, mount and thickness match. Still follow the manufacturers' recommendations, and fit new pads with a new rotor.
When should a rotor be replaced?
When it reaches the minimum thickness given by the manufacturer (often engraved on the rotor), when it is badly warped, or after oil contamination.
Do I need an adapter for 203 mm?
Yes, if your caliper was mounted for a smaller rotor: the adapter raises it by the required distance.
Matching products
- Campagnolo AFS Center Lock 160 mm – brake rotor — £28.21
- Galfer Fixed Disc Shark 1,8 mm MTB 6-bolt 160 mm – brake rotor — £46.83
- Hayes D-Series 6-bolt – brake rotor — £29.83
- Hope 4-bolt Rohloff 180 mm – brake rotor — £37.90
- Intend Massive 6-bolt 203 mm – brake rotor — £48.44
- Jagwire Basics BR1 6-bolt 203 mm – brake rotor — £15.29
- Magura MDR-C 6-bolt – brake rotor — £16.91
- Shimano RT-6B750 6-bolt – brake rotor — £30.68
- SRAM 6-bolt Centerline 180 mm – brake rotor — £26.60
- SwissStop Catalyst Pro 6-bolt 2-piece – brake rotor — £42.75
- Trickstuff Dächle-Disc HD 6-bolt – brake rotor — £24.98
- TRP RC03E Center Lock 2-piece with magnet 180 mm – brake rotor — £43.60