Your axle picks the lockring
A CenterLock rotor lockring is the threaded ring that holds a CenterLock brake rotor on your hub. Wolf Tooth makes two versions, and the one you need depends mostly on your axle. The Wolf Tooth External Spline lockring fits 12, 15 and 20mm thru-axles and quick release. The Wolf Tooth Internal Spline lockring fits 12mm thru-axles and quick release only.
So if your wheel uses a 15mm or 20mm thru-axle, the answer is the External Spline. If your wheel uses a 12mm thru-axle or a quick release, either one can work. Wolf Tooth makes the Internal Spline for frames and forks with tight clearance.
Which Wolf Tooth CenterLock lockring do I need?
"Spline" is the ridged pattern your tool grabs. On the External Spline the ridges are around the outside of the ring, and on the Internal Spline they are on the inside. That changes which tool you use.
The External Spline lockring works with 12, 15 and 20mm thru-axles and quick release. It uses the standard 4mm flange and 44mm outer diameter.
The Internal Spline lockring works with 12mm thru-axles and quick release only. Wolf Tooth makes it for frames and forks with tight clearance.
Wolf Tooth specifies 40 Nm for both the External Spline and Internal Spline lockrings, set with a torque wrench.
The Wolf Tooth Internal Spline lockring shown here has its tool notches on the inside of the ring, so it installs with a Pack Wrench fitted with Wolf Tooth's cassette lockring insert. Wolf Tooth makes it for frames and forks with tight clearance.
Two fit checks before you order
First, the hub. Wolf Tooth says the Internal Spline lockring does not work on Chris King and Project321 rear hubs, and to use the External Spline on those.
Second, road frames and forks. Wolf Tooth says the External Spline's standard 4mm by 44mm size fits all mountain bike frames and forks and many road frames and forks, but some road bikes need a special thinner lockring. Wolf Tooth asks you to check clearance on your bike before ordering.
Pack WrenchThe Wolf Tooth External Spline lockring installs with the Wolf Tooth Pack Wrench. The Internal Spline uses the Pack Wrench with Wolf Tooth's cassette lockring insert.
10.5g vs 8.5gWolf Tooth lists the External Spline lockring at 10.5g and the Internal Spline at 8.5g.
7075-T6Both Wolf Tooth lockrings are machined from 7075-T6 aluminum in Minnesota, with a stainless steel shim washer.
We carry the Wolf Tooth CenterLock Rotor Lockring, External Splined and the Wolf Tooth CenterLock Rotor Lockring, Internal Splined, in several anodized colors to match the rest of your bike.
Common questions
What is the difference between internal and external spline CenterLock lockrings?
The splines are the notches a tool grabs. External spline lockrings have them on the outside, and internal spline lockrings have them on the inside. They take different tools.
Which Wolf Tooth lockring fits a 15mm or 20mm thru-axle?
The Wolf Tooth External Spline lockring. It fits 12, 15 and 20mm thru-axles and quick release. The Internal Spline fits only 12mm thru-axles and quick release.
Which Wolf Tooth lockring fits a quick release hub?
Both the External Spline and Internal Spline lockrings fit quick release hubs. Wolf Tooth makes the Internal Spline for frames and forks with tight clearance.
Does the Wolf Tooth Internal Spline lockring fit Chris King hubs?
Not on the rear. Wolf Tooth says the Internal Spline is not compatible with Chris King and Project321 rear hubs, and to use the External Spline there.
How tight should a CenterLock rotor lockring be?
Wolf Tooth specifies 40 Nm for both its External Spline and Internal Spline lockrings. Shimano's hub manual also lists 40 N·m.
What tool removes a Wolf Tooth CenterLock lockring?
The External Spline installs with the Wolf Tooth Pack Wrench. The Internal Spline uses the Pack Wrench with Wolf Tooth's cassette lockring insert.
Before you order a lockring
Check your axle size, usually printed on the axle or listed in your wheel or fork specs. A 15 or 20mm thru-axle means the External Spline. A 12mm thru-axle or quick release can take either one. Wolf Tooth's CenterLock lockring page has the full specs.
Questions about your hub? Ask us. If you want the lab to swap rotors or lockrings, that is billed bench work.
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