Repair guides › Drivetrain

Remove and install a MicroSpline cassette

A 12-speed MTB cassette (often 10–51T) on a MicroSpline freehub, which has many thin splines so the small 10T cog fits. Only MicroSpline cassettes fit a MicroSpline freehub; HG and SRAM XD cassettes do not. Swapping cassette standards means a new freehub body or wheel.

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Tools

• Degreaser: Simple Green All-Purpose Cleaner ($)
• Shop rags + nitrile gloves: shop towels and nitrile gloves ($)
• Chain keeper (dummy hub): Park Tool DH-1 dummy hub ($)
• Bike grease: Park Tool PPL-1 PolyLube 1000 ($)
• Cassette lockring tool: Park Tool FR-5.2 ($)
• Chain whip: Park Tool SR-12.2 Sprocket Remover ($$)
• 12" adjustable wrench: Crescent 12 inch adjustable wrench ($)
• 3/8" click torque wrench 10–60 Nm: Pro Bike Tool 3/8 inch Drive Click Torque Wrench Set 10-60 Nm ($$$)

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Steps

1. Remove the rear wheel and the thru-axle.
2. Fit the Shimano lockring tool (TL-LR15 type) into the lockring. Wrap the chain whip around a middle cog so it pulls clockwise.
3. Hold the whip, push the wrench counter-clockwise until the lockring cracks loose.
4. Slide the cogs off in order. Clean the freehub body; a thin layer of grease prevents creaking.
5. Line up the wide spline and slide the new cassette on. Thread the lockring by hand, then torque.
6. Refit the wheel, torque the thru-axle and check indexing.

Torque

Diagram

Signs it needs doing

• Chain skips even with a new chain (worn cogs)
• Cogs wobble (loose lockring)
• Teeth look like shark fins

Problems this fixes

• Chain skips or jumps when pedaling hard