By Paul Norman

Published: Monday, 21 November 2022 at 12:00 am


If you buy a pair of Shimano clipless pedals, they’ll come packaged with a set of cleats for your shoes.

For off-road and urban SPD pedals, the cleats are made of metal and attached to the soles of your shoes with two bolts, whereas the road-specific SPD-SL plastic cleats are attached with three bolts (you can read our explainer on SPD vs SPD-SL pedals).

Shimano’s off-road pedals for mountain biking, gravel riding and cyclocross come with two-bolt cleats designated SM-SH51. However, look at the specs on Shimano’s site and it mentions the SM-SH56 as an optional cleat.

Shimano also has a range of ‘Explorer’ pedals, which feature the brand’s ‘Light Action’ release system. Most of these come packaged with the SM-SH56 cleats, with SM-SH51 cleats as an option.

What’s the difference between Shimano SH-SH56 and SM-SH51 cleats, and why might you choose one over the other? Let us explain.

What are SH51 and SH56 cleats?

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Shimano’s two-bolt SPD cleats are preferred for mountain biking and urban riding. But why are there two types?
Lawrence Crossman-Emms

There’s not much difference visually between the SH51 and SH56 cleats.

They’re both metal with two recessed bolt holes, which, if you’re cycling with cleats, attach to the soles of your shoes with the included bolts.

To fit the cleats, you’ll need to make sure your cycling shoes are compatible with the two-bolt SPD cleats preferred for mountain bike shoes and urban riding, not the three-bolt cleats used on road cycling shoes.

There’s an arrow at the front of each cleat to make sure you attach them to your shoes the right way round. They’re interchangeable between left and right shoes.

The only clue as to which type of cleat you have is the SH51 cleats are black, whereas the SH56 cleats are silver-coloured, plus there’s an M embossed on the rear-facing tab of the SH56.

You can buy Shimano SPD-compatible cleats from other brands, too. Look’s X-Track cleats offer two equivalent cleat options, designated X-Track, equivalent to SH51 cleats, and X-Track Easy, equivalent to SH56. The type of cleat is stamped on the front of the Look cleats’ undersides.

What’s the difference between SH51 and SH56 cleats?

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Shimano’s SH51 cleats are black, whereas the SH56 cleats are silver.
Stan Portus / Our Media

The difference between SH51 cleats and SH56 cleats is the number of directions in which you can release the cleat from the pedal.

SH51 cleats have a single direction of release; that’s to say you can only disengage from the pedal by pushing your heel out in a flat plane relative to the pedal, or by pushing it in.

The SH56 cleats, on the other hand, enable multi-directional release; as well as pushing your heel out or in, you can also roll your shoe on the pedal or pull up to release it.

The shape of the cleat is subtly different from the SH51 to enable this.