Bike crank Black Friday: discounts on e-bikes, BMX

A pair, one arm or the whole crankset?

We replace a twisted crank due to a fall, where the pedal thread is damaged, or to change the length. On a Shimano Hollowtech II, the axle is integrated with the right crank: the left one, held by two screws, is sold separately, like those of the FC-R7000 or FC-M8000 listed here. Elsewhere, both arms are sold in pairs, without chainrings and often without a bottom bracket. If the chainrings are worn too, a complete crankset from the cranksets in Black Friday will be easier to fit.

Crank length: 165, 170 or 175 mm?

The length is measured from the centre of the crankset axle to the centre of the pedal hole, and is engraved on the inner face of the arm. Adult bikes usually have lengths from 165 to 175 mm, depending on the frame size. A shorter crank limits pedal strikes in rocky sections and opens the hip angle at the top of the pedal stroke; young BMX riders go for 150 or 155 mm. Shortening by one notch requires raising the saddle by about the same amount, to maintain leg extension.

Square axle, ISIS, Hollowtech II or motor: check the interface

The interface tolerates no approximation. The square axle comes in two tapers, JIS and ISO, which do not mix; the ISIS is splined; recent cranksets use their own system, Hollowtech II from Shimano, DUB from Sram, Cinch from Race Face. On an electric bike, the crank fixes directly onto the motor axle: ISIS splines on many Bosch and Brose, JIS square on some Yamaha, with an offset specific to each motor to clear the housing. A crank does not change the assistance at all, and any derestriction of an electric bike remains prohibited.

Crank on sale: compare what's included

Before comparing the strikethrough price to the displayed price, make sure they refer to the same length, the same interface and the same content: a pair delivered with axle screws, cap or self-extractor is not equivalent to a single arm, and an electric bike crank must match your motor generation. Left cranks with Sram power meter sensors are detailed with the power meters in Black Friday. A crankset delivered without a bottom bracket is completed by bottom brackets. Outside of sales, the bike cranks page remains open year-round, and the new arrivals show the references that have recently come in.

What brands of cranks?

Shimano sells the left cranks of its Hollowtech II cranksets separately, from 105 to Dura-Ace on the road, from Deore XT to XTR in MTB, and from GRX in gravel.

Insight, a BMX race brand, offers short cranks from 150 to 165 mm, designed for young riders, as well as a version with an ISIS axle.

Stronglight, a manufacturer based in Saint-Étienne, designs the Magan cranks for electric bikes: Magan4 with ISIS splines for Bosch and Brose motors, JIS versions for Yamaha.

Praxis combines its carbon cranks Zayante and Doon with its M30 axle of 30 mm, and offers the eCrank in aluminium for Bosch and Yamaha motors.

E*Thirteen designs Helix Race cranks in aluminium or carbon, including E*Spec versions specific to each motor, Bosch, Brose, TQ or Fazua.

Race Face, a Canadian brand, fixes chainrings and spiders using its Cinch system; the Atlas, from 165 to 175 mm, features a 30 mm axle for enduro and downhill.

Frequently asked questions

How do I find out the length of my crank?

It is engraved on the inner face of the arm, near the pedal hole, in millimetres. If not, measure from the centre of the crankset axle to the centre of the pedal thread.

How do I remove a bike crank?

On a Hollowtech II, loosen the two screws on the left crank, then the cap with the proper tool. On a square or ISIS axle, an extractor screwed into the arm is required. Some cranks include a self-extractor: the axle screw is then enough to remove them.

Why does my crank have play?

Most often, a screw has come loose. Tighten to the specified torque without delay: a square axle crank that has been running loose can get damaged quickly, and its deformed housing will no longer hold the tightness.

Do I need shorter cranks on an electric MTB?

Many manufacturers offer them from 155 to 165 mm, as an electric MTB tackles technical climbs where the pedals easily hit the rocks. A shorter arm also suits the sustained cadence that most motors require.

Are crank discounts only valid on Black Friday?

No. The event centres around the Friday after Thanksgiving, but Vélo-Store applies its Black Friday discounts throughout November: you have time to check the length engraved on your arm before ordering.