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Your questions answered

The answers to all your technical questions, plus how to change a SRAM direct-mount chainring and our blu er’s guide to cranksets

1 Lift the chain o the chainring, then prepare to remove the crankset from the bike. Insert an Allen key (8mm or 10mm, depending on the crank model) into the bolt at the top of the non-driveside arm, so that it sits a few degrees clockwise of the crank arm.

2 Squeeze the Allen key and crank arm together, firmly, to loosen the bolt (it may be tight to undo). Keep turning the Allen key anticlockwise until the crank arm slides o the axle. Set it aside somewhere clean.

3 Tap the axle gently with a rubber mallet, then pull the remaining crank arm out of the frame from the drive side. Give the crankset a clean with degreaser. Use a pick to remove any dirt stuck in the heads of the bolts that hold the chainring onto the driveside arm.

4 Use a T25 Torx key to unscrew these three bolts, turning them anticlockwise. Store them somewhere safe. Then slide the chainring o the splined interface on the crank arm.

5 Ensure the new chainring is orientated correctly – the graphics should face the crank arm. Align the three slots on the chainring with the corresponding threaded holes on the crank arm, then push the chainring onto the splines.

6 Apply a little threadlock to the three chainring bolts. Slide them through the chainring and use a T25 Torx key to screw them into the crank arm, turning them clockwise. Use a torque wrench to check that they’re tightened to around 9Nm.

7 Grease the axle and push it through the BB from the drive side. Slide the non-driveside crank arm onto the splines on the other end, so that the crank arms are at 180 degrees to each other. Turn the crank bolt clockwise with an 8mm/10mm Allen key. Tighten it to 50Nm.