The freehub is the most mechanically active part of your wheel. Every pedal stroke loads and releases it. Every coast engages and disengages it. Over thousands of kilometres, the grease inside dries, contaminates with fine grit and metal particles, and begins to impede the mechanism that transfers power from your legs to your rear wheel. Most riders never service it until it fails.
A star ratchet freehub is simpler than it sounds. Two toothed rings — held in contact by a spring — engage each other to transmit pedaling force, then slip past each other when you coast. That is the entire mechanism. Clean, greased, and inspected every few thousand kilometres, it will outlast most other drivetrain components. Neglected, it will skip, delay, or eventually seize in the freewheeling position — a failure that is unpleasant on flat roads and dangerous on descents.
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STAR RATCHET SERVICE IN 30 SECONDS
• A star ratchet freehub uses two interlocking toothed rings held under spring tension — NOT individual spring-loaded pawls. Understanding the mechanism makes the service intuitive.
• The service interval is 3,000–5,000 km in dry conditions, shorter in wet or muddy riding. A sticky or delayed engagement is the first symptom of a service-overdue hub.
• Grease viscosity controls the character of the freehub: thick grease (e.g., Phil Wood Waterproof) makes it quieter but slightly slower to engage; thin grease or light oil makes it faster and noisier.
• The service requires no specialist tools — a cassette lockring tool, chain whip, and hex keys are sufficient for most hub designs.
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How a Star Ratchet Freehub Works
Knowing the mechanism before you disassemble it makes the service faster and the reassembly correct. A star ratchet system consists of two primary components: a drive ring fixed to the cassette body (the part the cassette slides onto) and a hub ring fixed to or integrated into the hub shell. Both rings have identical tooth profiles — typically 54 teeth, though tooth count varies by manufacturer and affects engagement angle.
A spring — either a single coil spring or a wave spring, depending on design — holds the two rings in contact. When you pedal, the tooth engagement locks the rings together and transfers torque from the cassette body to the hub shell. When you stop pedalling, centrifugal force and the spring allow the rings to slip past each other, producing the freewheeling click.
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Feature
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Star Ratchet
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Traditional Pawl System
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Engagement mechanism
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Two full-circle toothed rings under spring tension
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Individual spring-loaded teeth (pawls) on a ratchet ring
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Contact surface area
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High — full-ring tooth engagement
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Lower — only active pawls in contact
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Service approach
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Remove rings, clean, regrease surfaces and spring
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Remove pawls and springs individually, clean ratchet ring
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Sound character
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Medium-frequency click; quieter with thick grease
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Higher-frequency rapid clicking
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Grease sensitivity
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High — viscosity directly affects engagement speed and noise
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Moderate — pawl springs compensate for partial grease migration
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Repairability
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Replace individual rings if worn
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Replace pawl springs or complete ratchet ring
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Tools and Supplies Required
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Cassette lockring tool (matching your cassette standard — Shimano HG, SRAM XDR, Campagnolo)
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Chain whip
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Hex keys (typically 5mm and 6mm for axle and end cap removal)
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End cap removal tool if required by your hub design (often included with the wheelset)
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Clean rags and a container for parts
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Degreaser (isopropyl alcohol or a citrus-based bike degreaser — avoid petroleum solvents on sealed bearing housings)
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Freehub-appropriate grease (see grease section below)
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Optional: thin synthetic oil for the spring contact surface
Step-by-Step: Stripping and Cleaning
Remove the cassette first. Apply the chain whip to the cassette to prevent rotation, fit the lockring tool to the lockring, and loosen anti-clockwise. Slide the cassette off the freehub body and keep the spacers in order.
With the cassette removed, the freehub body is accessible. On most star ratchet designs, the freehub body is removed by unscrewing the non-drive-side end cap (which releases the axle) and sliding the freehub body off the hub shell. Some designs use a hex bolt at the non-drive end; others use a proprietary tool. Consult the hub documentation if the procedure is not immediately obvious — do not force anything.
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Once the freehub body is off, the drive ring typically drops out with it. The hub ring remains seated in the hub shell. The spring sits between the two rings — note its orientation before removing it.
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Remove both rings and the spring. Lay them on a clean rag in order — drive ring, spring, hub ring.
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Clean all three components with degreaser on a clean rag. Remove all old grease and any metal shavings or grit. Inspect the teeth for wear — rounding of the tooth tips indicates the rings need replacement.
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Clean the bore of the hub shell where the hub ring seats, and the bore of the freehub body where the drive ring seats. Old grease here becomes contaminated and acts as an abrasive.
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Inspect the sealed cartridge bearings in the freehub body at this point — spin them on your fingertip. Any roughness or grittiness means a bearing replacement is due.
Grease Selection and Application
Grease choice for a star ratchet freehub is a rider preference decision within a defined range. The mechanism will function correctly across a wide viscosity range; what changes is the character.
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Grease Type
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Engagement Speed
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Sound Level
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Reapplication Interval
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Best For
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Thick waterproof grease (e.g., Phil Wood Waterproof, Park Tool HPG-1)
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Moderate — rings engage at slightly lower rotational speed
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Quiet
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3,000–5,000 km
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Wet conditions, year-round riders who prefer quiet
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Lightweight synthetic grease (e.g., Finish Line Teflon, Dumonde Tech Lite)
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Fast — rings snap into engagement quickly
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Moderate click
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2,000–3,000 km
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Dry-condition riders, those who prefer fast engagement
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Thin synthetic oil (e.g., Squirt, T-9 applied sparingly)
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Very fast
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Loud click
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1,000–1,500 km
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Race-day or summer-only; frequent service needed
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No lubrication or dried grease
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Unpredictable — may seize or delay
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Irregular
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Immediate service required
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Not acceptable — causes premature wear
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Apply grease to both faces of the drive ring teeth, the hub ring teeth, the spring contact surfaces, and the bore where the rings seat. Use enough to coat the surfaces evenly — a thin, visible film. Excess grease will migrate and contaminate the bearings.
Reassembly and Verification
Reassemble in reverse order: hub ring into the hub shell bore, spring oriented correctly (coil spring: free end facing the drive ring; wave spring: flat faces against both rings), drive ring onto the spring. Slide the freehub body onto the hub shell, aligning the splines.
Thread the end cap and axle assembly back in — hand-tight, then the specified torque for your hub (typically 5–8 Nm for an axle end bolt; check your hub specification sheet).
Thread the end cap and axle assembly back in — hand-tight, then the specified torque for your hub (typically 5–8 Nm for an axle end bolt; check your hub specification sheet).
Before reinstalling the cassette, do a function check: hold the wheel and spin the freehub body in the drive direction — it should turn freely. Spin it in the pedaling direction — it should immediately lock and turn the hub shell with it. If it slips in the drive direction or locks in the coast direction, the spring is inverted or the rings are misaligned. Disassemble and check the spring orientation.
The Star Ratchet Hubs Worth Servicing
A service is only as satisfying as the mechanism it restores. Hubs that are built with close-tolerance machining, standard replacement parts, and accessible disassembly reward regular maintenance with long, reliable service life. Hubs that are poorly toleranced or use proprietary non-replaceable parts create a situation where service is either impossible or not cost-effective.
The star ratchet freehub on the NxT SL2 and QianKun wheelsets is designed to be maintained at home with standard tools. Both lines use the star ratchet architecture — two interlocking toothed rings held by a spring — making the service process described above directly applicable. The NxT SL2 is engineered to an internal 120J impact standard, three times the UCI minimum, and tested to 100,000 pedaling-fatigue cycles at 1,100N. QianKun wheels feature individually replaceable carbon spokes, so the wheel as a system is built around the same serviceability philosophy as the hub itself. Keep the freehub greased and the bearings clean, and these wheels are designed to stay in service for years of demanding riding.
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HOW YOELEO BUILDS FOR HOME SERVICEABILITY
• Star ratchet freehub system on NxT SL2 and QianKun — two toothed rings and a spring, serviceable with standard tools at home
• NxT SL2 engineered to an internal 120J impact standard, three times the UCI minimum — hub and rim built to maintain dimensional accuracy under sustained load
• Tested to 100,000 pedaling-fatigue cycles at 1,100N — the wheel system is tested for the loads that freehub and hub shell must sustain together
• QianKun individually replaceable carbon spokes — wheel serviceability extends beyond the hub to the entire spoke system
• Hand-trued NxT SL2 before shipping — spoke tension is set to spec from the first ride, reducing the variables that complicate hub service intervals
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Frequently Asked Questions
How often should I service my star ratchet freehub?
Every 3,000–5,000 km in dry conditions, or after significant wet-weather riding. The first symptoms of a service-due hub are a delayed or sticky engagement when you resume pedaling after a coast — the rings are not snapping into contact cleanly. Service at the first sign rather than waiting for the problem to worsen.
What grease should I use in a star ratchet freehub?
A thick waterproof grease such as Phil Wood Waterproof or Park Tool HPG-1 provides the longest service interval and the quietest operation. For faster engagement at the cost of more frequent servicing, use a lightweight synthetic grease. Avoid petroleum-based greases that may degrade the elastomers in sealed bearings nearby.
What is the difference between a star ratchet and a pawl freehub?
A star ratchet uses two interlocking full-circle toothed rings held in contact by a single spring. A traditional pawl system uses individual spring-loaded teeth that catch on a toothed ratchet ring. Star ratchet designs have a larger total contact area, making them well-suited to high-torque applications like sprint efforts, while pawl systems are lighter and easier to source parts for.
My freehub skips under hard pedaling efforts — is this a grease issue?
Skipping under load typically means the ratchet teeth are not engaging properly. This can be caused by dried or contaminated grease (service the hub first), worn teeth on either ring (inspect tooth profile after cleaning — replace rings if tips are visibly rounded), or a fatigued spring that no longer holds the rings in firm contact (replace the spring).
