Crankset fitting instructions

Document SC-IP-CR-001 · Revision A · October 2026

If you bought your crankset with one of our bikes, it arrives fitted and set up. This page explains how it goes together, how to set the bearing preload, how to fit a chainring, and how to remove and refit it. It covers both versions of the crankset: standard and WIDE (gravel).

Download PDF Fitting the crankset Standard and WIDE

Before you start

Important

Cranks carry all of your pedalling load. If you are not confident fitting them, have them fitted by a qualified bicycle mechanic.

Always fit the supplied pedal washers. See Pedals and pedal washers.

Fit and look after the bottom bracket following its maker’s instructions.

Fits: bottom brackets for a 30 mm axle, in almost all frame types. It does not fit original BB30 frames: their bearings sit too far inboard to reach the bearing seats on the axle.

Tools and torque settings

Torque wrenches covering 1–5 Nm and 50 Nm
10 mm hex bit (crank bolt)
T20 Torx bit (chainring bolts)
T8 Torx key (grub screw in the preload collar; also used to turn the collar)
Anti-seize, for all threads and spline fits
The tool your pedals need

Fastener	Tool	Torque
Crank bolt (drive side)	10 mm hex	50 Nm
Chainring bolts ×8 (M4 countersunk)	T20 Torx	4–5 Nm
Preload collar	T8 Torx key in the grub screw, as a lever	Just enough to take out the float
Grub screw (M4, locks the collar)	T8 Torx	1 Nm
Pedals	Pedal tool	Your pedal maker’s figure

Crankset parts

Part	Qty	Notes
Non-drive arm with axle	1	The 30 mm axle is permanently fixed to this arm
Preload collar	1	On the non-drive arm
Grub screw, M4 (T8 Torx)	1	Locks the preload collar
Drive arm	1	Crank bolt (10 mm hex) and self-extracting cap fitted
Spline spacer (WIDE only)	1	Fitted in the bottom of the drive arm’s spline. Leave it in place
Pedal washers	2	Always fit: one in each arm

Not included with the crankset:

Bottom bracket and axle float spacers. Supplied with our bikes. If you buy a bottom bracket separately, it should come with the axle float spacers to suit it.
Chainring. Sold separately. It comes with its eight M4 countersunk bolts.

Bottom bracket and axle float spacers

Section through the axle: bearing seats, axle float spacers each side, preload collar, crank bolt and the frame centreline

Section through the axle. The bottom bracket and axle float spacers are shown for illustration only: yours may look different.

Our recommended bottom bracket is the Enduro MAXHIT. Suitable bottom brackets for a 30 mm axle are made for almost all frame types, except original BB30 frames.
The axle has bearing seats near each end. The bottom bracket bearings must sit on these seats.
Axle float spacers go on the axle either side of the bottom bracket bearings. They set where the crankset sits, so that it is centred on the frame: both arms the same distance from the frame centreline.
How many spacers you need, and how thick they are, depends on the bottom bracket and on where its bearings sit. They are part of the bottom bracket assembly, not the crankset.
Our frame kits: if your crankset came with one of our frame kits and our recommended bottom bracket, the frame kit instructions list the exact axle float spacers for that setup. Use those.
When you take the crankset off, keep each spacer on the side it came from and refit it there.
If you fit a different bottom bracket or move the crankset to another frame, the spacers may need to change. Ask us if you are not sure.

Standard and WIDE cranksets

The WIDE (gravel) crankset sits wider on the bike. Its axle splines are 2.5 mm shorter, so the axle goes 2.5 mm less far into the drive arm. A 2.5 mm spline spacer, fitted in the bottom of the drive arm’s spline, fills that space, so the crank bolt clamps the arm firmly onto the axle. Everything else on this page is the same for both versions.

Which version do you have? WIDE cranksets are engraved on the arm to show it. If yours has no engraving, it is either a standard crankset or a WIDE one made before we started engraving them. To check, take off the drive arm and measure the length of the splines on the drive end of the axle. Measure only the part where the sides of the splines run parallel to the axle, not the chamfer where the splines start (see the drawing below): about 13 mm on a standard crankset and 10.5 mm on a WIDE crankset. If you are still not sure, contact us with your order number.

Section through the drive arm: standard axle sitting on the bottom of the spline with 13 mm of parallel spline; WIDE axle with 10.5 mm of parallel spline and a 2.5 mm spline spacer

WIDE cranksets: the spline spacer must be fitted

Never fit a WIDE drive arm without its spline spacer. Without it, tightening the crank bolt to 50 Nm squeezes the arm instead of clamping it onto the axle.

Never fit a spline spacer to a standard crankset: the drive arm would not go fully onto the splines.

The spacer comes fitted in the drive arm. Leave it in place.

Fitting the crankset

Fit the bottom bracket to the frame first, following its maker’s instructions. The video at the top of this page shows these steps.

Anti-seize. Put anti-seize on the splines at both ends of the axle and on the crank bolt thread.
Preload collar. Make sure the preload collar is wound back towards the non-drive arm and the grub screw is loose.
Non-drive spacers. Slide the non-drive side axle float spacer(s) onto the axle, up to the preload collar.
Axle. Slide the axle through the bottom bracket from the non-drive side.
Drive side spacers. Slide the drive side axle float spacer(s) onto the axle.
Drive arm. If you are fitting a chainring, fit it to the drive arm first: see Fitting a chainring. Then fit the drive arm onto the axle splines. WIDE only: first check the spline spacer is in place in the bottom of the drive arm’s spline.
Crank bolt. Tighten the crank bolt to 50 Nm with a 10 mm hex bit.
Preload. Fit a T8 Torx key into the grub screw and use it as a lever to turn the preload collar so that it unscrews along its thread, moving towards the bottom bracket, until the side-to-side float has just gone. How far depends on your bottom bracket bearings: don’t overtighten it.
Lock the collar. Tighten the grub screw to 1 Nm to lock the collar.
Check. Push and pull the arms sideways: there should be no float. Spin the cranks: they should turn freely.
Pedals. Fit a pedal washer and then the pedals: see Pedals and pedal washers.

Fitting a chainring

Fit the chainring to the drive arm before the arm goes on the bike. The bolts go in from the back of the chainring, so you can’t reach them with the arm fitted.

Line up the keyed lobes. One lobe of the spline on the arm, and the matching lobe on the chainring, is filled in, so the chainring only fits one way. Line them up and push the chainring onto the arm.
Bolts. Put anti-seize on the threads of the eight M4 countersunk bolts and fit them from the back of the chainring.
Tighten. Tighten the bolts evenly to 4–5 Nm with a T20 Torx bit.

Labelled drawing: keyed lobes and chainring bolts

Drive arm inboard face, chainring centre and the eight chainring bolts, with the keyed lobes labelled

Pedals and pedal washers

Always fit the pedal washers

Each arm has a shallow recess around the pedal thread, and a pedal washer sits in it. Not all pedals have a machined thread relief on the axle. Without the washer, a pedal like this puts a large stress concentration on the first thread of the crank arm, which is very likely to lead to early failure.

Half-section of the pedal thread in the arm, with and without the pedal washer

Put a pedal washer in the recess on each arm before fitting the pedal.
Fit and tighten the pedals following the pedal maker’s instructions, with anti-seize on the threads. The left pedal has a left-hand thread.

Removing the crankset

The drive arm is self-extracting: the cap fitted in it pushes the arm off the axle as you undo the crank bolt.

Loosen the grub screw in the preload collar. With the Torx key still in the grub screw, screw the collar back towards the non-drive arm.
Undo the crank bolt with a 10 mm hex key. After it loosens, it will go tight again as it pushes against the self-extracting cap. Keep turning: this pushes the drive arm off the axle.
Take off the drive arm and the drive side spacer(s). WIDE only: leave the spline spacer in the drive arm.
Slide the axle and non-drive arm out of the bottom bracket. Keep the spacers on the side they came from.

Don’t remove the self-extracting cap.

Looking after your crankset

After your first few rides, check the crank bolt is still at 50 Nm and that there is no side-to-side float. Check again regularly after that.
If float appears, reset the preload: loosen the grub screw, use the Torx key in it to turn the collar until the float has gone, and tighten the grub screw to 1 Nm.
Don’t aim a pressure washer at the bottom bracket.

Questions? Contact us.

Warranty

Everything we make is guaranteed for the lifetime of the original owner against defects in design, materials and workmanship. If a part we made fails because of a defect, we will repair or replace it.

Parts we buy in are covered by their makers’ warranties. Enduro bottom bracket bearings carry Enduro’s limited lifetime warranty: contact us or Enduro directly to make a claim.

Not covered:

crash or impact damage
damage from fitting or use that doesn’t follow these instructions, including riding without the pedal washers
modified parts
normal wear and cosmetic marks

To make a claim, contact us with your order number (your order confirmation email is your proof of purchase) and photos of the problem. Stop riding a part you think is damaged.

This guarantee is given by Sturdy Cycles Ltd, The Old Tannery, Lower Keyford, Frome, BA11 4AR, United Kingdom. It applies worldwide to products bought from us or an authorised dealer. It is in addition to your legal rights as a consumer and does not affect them. See also our terms of service.

Revision history

Rev	Date	Change
A	October 2026	First issue (standard and WIDE)

This page is document SC-IP-CR-001 revision A. The PDF version has the same content.

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