OK, so you want to ride your mountain or road bike clipless, and we are assuming you will go with the SPD system, so let’s recap what you will need:
As I have described in detail elsewhere there are actually two SPD systems produced by Shimano – plain SPD and SPD-SL. At risk of oversimplifying, the former is used primarily by mountain-bikers, while the latter by road cyclists. The two systems are effectively incompatible, EXCEPT that many SPD shoes will have holes/slots to take both types of cleat, and there are also adapters available to allow you to use SPD-SL shoes on an SPD pedal (though I am not sure about the other way around, maybe someone can help me on that one). However, you MUST have the right cleat for the right type of pedal – SPD for SPD, SPD-SL for SPD-SL.
The cleats used in the SPD and other clipless systems are basically a rigid metal or nylon resin (in the case of SPD and SPD-SL respectively) plate with no moving parts that screws into the bottom of your SPD shoes and is engineered in such a way that when pressed down firmly on the pedal it prises apart the spring mechanism on the pedal which then snaps shut around the cleat and fixes your foot, and cannot easily be removed. The shape of the cleat is such, though, that rotating the shoe – usually outwards, a motion you would not naturally perform when riding – levers apart the pedal’s ‘jaws’ once again and the cleat springs out and you are free! Simple but ingenious and it has revolutionised clipless riding.
Here is a picture of a regular pair of SPD cleats
…and a set of SPD-SL road cleats.
You will immediately be struck by the huge difference between them!
By the way, the cleats are shown ‘exploded’ here – what you see in the first picture (Shimano SH51) is the backplate which goes inside the shoe, on the other side of the slots, into which the actual cleat screws. Below it in the same picture is the actual cleat and then below that are the mounting screws. The SPD-SL cleat (SH11) is also pictured disassembled.
Because of the scale of the photos you maybe can’t appreciate that the MTB cleat (top) is MUCH smaller than the road cycling clear below – not much more than a third of the size maybe. The mountain bike SPD cleat is much smaller for a number of reasons: mainly because its small profile allows it to be recessed in the shoe, between the treads, which allows the rider to dismount and walk, push or carry his bike on rough terrain. The large road cleats would obviously be a massive hindrance. Indeed, walking in road shoes with SPD-SL cleats is very ungainly and is avoided by riders as much as possible – the cleats get worn that way, apart from anything, (though rubber covers can be bought for SPD-SL cleats) and it is very awkward too. But the advantage for the road rider is that a much greater surface of his or her foot is connected to the SPD shoe, and therefore the pedal, a fact contributed to by the three anchor points on the shoe too, theoretically giving greater stability and efficiency.
Obviously when choosing SPD cleats your primary concern will be that they are of the correct type for your shoe – SPD or SPD-SL (two-slot or three-hole respectively). If you are going SPD for the first time, perhaps it would just be safer to stick with Shimano parts. Shimano have two basic models of SPD cleat (the SH51 and the SH56) and two models of SPD-SL (the SH10 and the SH11), which makes things pretty simple – ignore the others you see around for now. The differences are as follows:
The difference is in the amount of ‘float’ available.
What is float? Basically it refers to the amount of play your foot has whilst clipped in – some prefer to have absolute rigidity, while others, especially those with a tendency to knee problems, prefer to have a little float left and right. This is fixed at 6 degrees for the SH11 and can’t be adjusted per se, though adjusting the tension on the pedal will give you a little room for manoeuvre.
Extra float CAN make it a little more difficult to unclip, because you have to overcome the extra play before you can release, so a cleat with minimum float (i.e. the SH10) might be a better bet for SPD beginners.
By the way, a nice detail with these Shimano SPD-SL cleats is that the coloured details on them gradually wear down with use, and when the paint is worn right off you know that it’s time to change the cleat. I will get round to cleat wear in another article, but suffice to say that cleats do get worn down eventually and start to move around and even unclip themselves at inopportune moments.
The difference between the two main Shimano regular SPD cleats has nothing to do with ‘float’ – the basic difference is as follows:
Multi-release (SH56) means that you can unclip from the pedal by turning your heel in any direction and popping out. The thinking goes that this is a better option for those new to SPD, since they can get unclipped more easily in a pinch. Single-release cleats (SH56) only unclip when you turn your heel outward, which means it is theoretically harder to unclip accidentally. A few thoughts about that: firstly you CAN unclip with SH51s by rotating your heel inwards too, it’s just not as easy. So they are not truly single-release. Multi-release cleats are often supplied with new pedals for some reason, not sure why, and it is tempting for newbies to go with what seems like a ‘safer’ option, but my own approach was to ditch the multis I got with my first SPD pedals and put single-release on straight away. Why learn bad habits with this ‘halfway’ option? I just felt it was better to jump in the deep end and learn with single-release, as I would have graduated onto them anyway as multi-release do not seem like a good idea for racing purposes – there is more chance of them popping out at inopportune moments. You may think differently, but I thought it was worth mentioning.
About the colours (black and silver respectively), these seem to play no significant role here other than in distinguishing them when they are new. The black finish on the SH51s gets worn off after just a couple of rides and it ends up looking the same as the SH56. Incidentally, I have studied these two cleat types closely, and I am darned if I can tell what the physical difference is, i.e. how the ‘multi-release’ effect is achieved! I suspect it’s down to a very small difference in some of the angles on the cleat, and like I say, single-release cleats are ‘multi’ to an extent in any case.
I hope that has served to clear up any mystery surrounding SPD cleats for you and you will now easily be able to make your choice depending on your needs. Leave a comment here if you have any questions, or if I have missed anything out!