In this section we are going to cover the basic different types of pedal that are compatible with the SPD system.
If you are still a little mystified about SPD then rather than explaining SPD and the basic different types of SPD locking system all over again, we recommend you check out our article about SPD shoes and also the one about SPD cleats. These should bring you up to speed.
If you are thinking about “going SPD”, the pedals may well be the first thing you consider before taking a decision about cleats and shoes, because what cleats you buy will depend entirely on what pedals you opted for, and the type of shoes you buy will also be limited by the cleats. Of course, the type of riding you do is really what it is all about, so let that inform your decision first and foremost – whether to go for SPD, SPD-SL or perhaps not SPD at all but one of the other systems (which we will not cover here). Based on the factors we have talked about in those other articles, you will have probably gone for SPD if you are a mountain-biker (or doing spinning classes, or trekking, and some other styles of riding too), while if you do most of your riding on a road bike, you will probably have gone for SPD-SL.
SPD pedals explained
SPD pedals are designed to fit the SPD type of cleat, usually the Shimano SH-51 and SH-56 type that we covered here. As a brief reminder, the SH-51 and SH-56 type differ only in the range of movements that allow release from the pedal and both are compatible with all types of SPD pedal. The classic SPD mechanism is basically a powerful set of “jaws”, as you can hopefully see in the picture below, of the Shimano PD-M520 SPD pedal:
I hope this diagram helps a little – the red line marked 1 above is supposed to show the rotation of the back part of the pedal. This part has a strong spring and when you are not clipped in, this “back jaw” is clamped shut, towards the front jaw, which is completely fixed (doesn’t move). When you want to clip yourself in, you first clip the front, somewhat round, pointed end of the cleat into the front jaw and then press down with the back of your shoe. Because of the anatomy of the cleat at the back, it will prise open the back jaw enough for the back of the cleat to pop under it, at which point the jaw will snap closed over the back lug on the cleat and will be near-impossible to reopen by the reverse motion, since the shape of the cleat does not allow this. A lot simpler than it sounds, once you’ve tried it, I assure you! The other arrow in the above picture indicates the motion your heel has to go through in order to unclip your foot. When you rotate your heel in this way, the shape of the cleat once again allows it to prise the back jaw open and your foot pops out.
Different types of SPD pedal
The PD-M520 shown above is one of the most widely sold SPD pedals, typical of all racing/serious recreational SPD pedals in that it actually has a twin mechanism, i.e. two sets of jaws, one on each side, making it that much easier to clip in quickly without hunting blindly for the mechanism (unlike SPD-SLs – see later on).
The other type of SPD pedal you will sometimes come across is the mixed platform/clipless type. The idea behind this is that you can ride with normal shoes/trainers/sneakers/whatever using the flat, platform side of the pedal, around town or any setting where SPD just isn’t necessary. When you DO want to be clipped in, you wear your SPD shoes and use the flip-side of the pedal with its single SPD mechanism. This is a common, bog-standard pedal of this type from Shimano, the PD-M324:
Or the somewhat more stylish Shimano PD-A530:
I have talked about these combo style pedals elsewhere, but let me give you my thoughts on them again – the M324s were the first SPD pedals I bought. I, like many others, figured if I was going SPD for the first time, I was best off getting the combo type so I could always fall back on the platforms anytime. The truth is though, I probably shouldn’t have bothered – I actually tried to use these in my first racing season and went crazy after a couple of races. I must have lost in the order of minutes trying to flip the pedal over to the correct side to get clipped in whenever I unclipped for any reason. If you are riding mostly MTB or anything more than recreational riding, then just get full-SPD, trust me. You will soon get used to it, and wonder how you did without. You probably won’t ride your offroad bike around town much (well, you shouldn’t be, if you want to hold onto it for any length of time) and eventually the platform side just becomes a pain. And anyway, you can ride the SPDs with ordinary sneakers, at a push, if you really have to. Just my opinion.
Although these look a lot different from their SPD counterparts, and the cleats look quite a bit different too, the principle is pretty much the same. Check out these Shimano PD-R540 SPD-SL pedals:
Although they look kind of spacey compared to regular SPD pedals, the principle is very much the same – the front of the cleat is inserted under the front edge of the pedal and pressed down at the back – the back “jaw” pops shut over the back part of the cleat and can only be removed with a twist of the foot. One major difference you will see here is that SPD-SL pedals are not double-sided. The logic behind this, presumably, is that in road cycling there is not a need to frequently unclip and reclip rapidly as in mountain-biking, where a race could be won or lost in a “find the right side of the pedal moment” (as I mentioned earlier with the dual platform SPDs).
More on “clipless” pedals
There is plenty more that could be said about these two main types of pedal, and about riding clipless in general. Check out the rest of the site for lots of other stuff on this topic.
A few more “frequently asked questions” worth answering here:
– Does it matter which side of the bike which pedal goes on?
Bike pedals come in pairs (OK, you figured that bit out yourself!) and have a “left” and a “right” pedal, usually marked somewhere with an L and an R respectively. When being installed, pedals cannot be substituted, since the left pedal has a reverse thread so that it doesn’t come unscrewed due to the rotation (but in fact tightens as you ride, effectively). Also, with SPD-SL pedals, you would quickly realise your mistake if you put them on your bike the wrong way round (think about it!) 🙂
– What is the allen/hex bolt for on the pedal?
SPD and SPD-SL pedals always have a tensioning bolt which basically increases or decreases the ease with which you can unclip by tightening or loosening the spring. There is an art (maybe a science too) to properly tensioning pedals. Too tight and you will have trouble getting out in a critical moment (like at the traffic lights!). Too loose and your foot can pop out when you least want it to, like when you hit a bump at high speed.
– What is the difference between a cheap SPD pedal and an expensive SPD pedal?
OK, maybe this is oversimplifying things, but like most bike parts this is mostly a question of weight. Once you get beyond the cheapo price-point and build quality is assumed, then the weight factor comes into play. So there is not much difference quality-wise between a $50 pair of pedals and one that costs $150, but the latter will be somewhat lighter (though usually not 3 times lighter!). Without getting into the whole weight-weenies argument, there comes a point of diminishing returns, with pedals as with everything. If you think a 200g lighter pair of pedals is going to make a difference to your performance, and is worth paying $100 more for (made-up numbers, just illustrating the point) then go ahead. Those of us with more sensitive budgets will probably live with the extra weight. Oh yes, and more expensive does not necessarily mean more durable. On the contrary, expensive pedals and other bike parts are often made of lighter alloys that wear more quickly…
– What special maintenance do SPD pedals need?
What maintenance does a bike need? For me this is a question of how much time I want to spend endlessly preening my bike versus riding the darned thing. Of course some basic maintenance is necessary, but this has a diminishing return too – my personal philosophy is, do the bare minimum of maintenance to ensure a reasonable service life, and spend as much time as possible RIDING!! With SPD pedals, the main thing is to keep the mechanism free of mud, which can prevent it opening and closing properly, and even stop your cleat clipping in at all. So I like to give the pedal a careful pressure wash when I can, to blow out all the bits of dried mud without getting any water in the bearings, and then to oil the springs and other moving parts of the mechanism. I also lube up the surface of the back “jaw” where the cleat is going to rub on its way in – I find that does make for a nice smooth entry. Some people also give their pedals a full oil bath every now and then. I personally didn’t find that helped much. When a pair of pedals go, it’s usually the bearings that just wear out – I actually had a pedal practically break off altogether, after a very long life. Park Tool have a very good article on how to overhaul your SPD pedals. Again, I just wonder if it’s worth the hassle…
Well, there’s plenty more we could say about SPD pedals, and the whole experience of riding them. Check out some of the other articles on the site, for example the Going Clipless page, for more on the subject! Oh, and leave a comment here if you think there is something that should be added to this article, or something you totally disagree with!
Read up on some specific models of SPD pedals:
[catlist name=”SPD pedals” numberposts=”10″ orderby=”rand”]