yaw

Since it's not generally easy to just try each system out for a bit before buying, I thought I'd share my observations on the differences between the two systems for those on the fence or looking to switch for whatever reason. There's obviously a lot of content on this out there, but I think certain aspects are overemphasised for the sake of comparison, making these characteristics sound a bit more drastic than they really are - which skewed me in the wrong direction initially.

Bit of background
When I first got a bike I chose SPD simply because I thought it would be very awkward to walk on those giant SPD-SL cleats and favoured the convenience of double sided pedals. I also assumed a lighter release action would be a bit better for traffic lights.

To be fair
As part of this comparison, I am taking into account that I went from a mid tier Shimano shoe with a mid level stiffness sole to a flagship Bontrager shoe with a very stiff carbon sole and SPD-SL pedals that cost 3-4 times as much as the SPD pedals. So there is obviously an added degree of immediacy and feel from a 270g+ lighter and considerably stiffer setup that feels better just on that account, which is why I will try to keep it to the more general observations. There may still be some variations due to equipment I am missing, feel free to add to the discussion.

What I got wrong about SPD
It took about 3 days of riding and coming unstuck twice under load between enjoying the light clipping action and moving to the halfway spring setting and then soon to the hardest spring setting. I also soon realised that the convenience of dual sided entry, whilst it is a real practical benefit, is not really a concern when you know what your pedals are doing and get used to the motion, and it will easily cost 150-200g in weight just between a single or dual sided Shimano SPD pedal with otherwise identical quality. Anyone at the point where that amount of weight on a bike gets really expensive, the single vs dual SPD pedal price difference is comparatively very cheap, too cheap not to go single, really. Another surprise was that whilst one can obviously walk very well with recessed SPD cleats on flat floors, it really starts to suck when walking on coarse surfaces where the metal really scrapes and wears, which often led me to walk on the outsides of my feet, which really was not the point. Further, it seems like once SPD shoes are worn, the cleats will no longer be as recessed AND the wider contact patch on the side of the pedal gets lost, leaving the shoe to sit on the cleat only.

What I got wrong about SPD-SL
Every source seemed to overstate the difficulty of walking with SPD-SL cleats, to the point where it was a major deterrent for me based on pure theory. Yet the rubber studs on the cleats make it so much easier to walk than I expected. I assumed it would be a slippery hard plastic feel, which it is absolutely not. On coarse ground, I actually prefer it as there are no metal cleats to get awkwardly scraped, and on all other surfaces, it's perfectly fine for anyone who rides their bike to ride a bike, not to run a ton of errands. What is more, these cleats are cheap and can be replaced when worn down, which is much better than replacing an entire SPD shoe because its protruding tread wore down and lost all contact to the frame of the pedal. The unclipping force required with SPD-SL is definitely greater, at least with my set of Ultegra pedals, where the lightest SPD-SL setting feels near as hard to get out as the tightest SPD setting, but then again this is where I quickly ended up on SPD for the sake of trusting my bond to the pedals and not crashing.

Perceived differences when riding
There are a lot of other equipment factors to consider here, but in general one of the main things I heard about was the small (SPD) vs larger (SPD-SL) contact patch and associated performance and comfort differences. I would say that on a decent SPD shoe with reasonably stiff sole and good tread, there is no major pressure point over the cleat, and force is transferred well enough so as not to matter to those who do not constantly have one eye on their power figure. With a sloppy sole and poor tread, sure I can see how the small contact patch may shine through, but this was never an issue on my SPD setup. But there is still a difference in how these two systems feel, simply because the way the foot pivots with float. The SPD shoe pivots around a much more defined point, whereas the SPD-SL feels like it pivots on a larger base, which is probably why it feels like there is a broader platform under the foot. I think the perceived difference would be far less under controlled circumstances with equally stiff carbon soles and 0 degree float. This aside, I feel that the SPD-SL engagement is more reliable and has a more resolute feedback upon engagement, whereas the SPD system seems to have a bit less tolerance, meaning one has to aim a bit better so as not to stab around on the pedal, which feels awful being metal on metal, rather than plastic on carbon composite. Fit adjusting SPD-SL cleats also seems a bit smoother. So in the end, I overestimated the benefits of SPD that turned out not so great in the real world, and overestimated the downsides of SPD-SL that were surprisingly extremely mild to non-existent, with a number of key factors in favour of SPD-SL.

Keen to hear from other riders that either swear by either system or tried both. I will certainly be going around on SPD-SL, first order of business being to swap from the yellow to blue cleats for a bit less float. Once these are through, I may even try Speedplay, but 4 hole shoe selection was a bit too limited without messing with additional adapter plates.

TiHabanero

I ride both style pedal/shoe combos and find them very similar in feel. The very positive contact engagement of the SPD SL is a benefit as I know for certain when I am connected to the pedal. One thing to note about the SL cleats and walking is that the rubber grips will wear and tear over time. The only walking on mine is when I move the bike from the back door to the walkway and vice versa when finished with the ride. The rubber things are still perfectly fine after 4 years of use. On the other hand my son's wore off after his first season as he was walking in and out of is apartment and walking to his office in a building at work. He replaces his cleats every two years.

Chuck M 

After riding toe cages and straps since I was a teenager, I bought a modern bike a few years ago and decided I needed to go clipless on it. My SPDs were IMHO a waste of money. I had been influenced by online horror stories of how hard clipping in an out was and thought the double sided SPDs were the smart move. The guy at the LBS tried to talk me into SPD-SL or Look compatible but I believed what I read online.

Now I have a heavy pair of SPSs on a shelf in the garage and a composite pair of Look compatible pedals on my bike. I'm not saying SPD on a road bike is wrong as many prefer them, but I wish I would have listened to the guy at the LBS. By the way, this was before I joined Bike Forums so I may have got better advice on how to choose the right pedal for me here. I think what I had read came from a site that can't be typed here.

mcours2006

I am equally comfortable on both types of cleats. Half my bikes have SPD, which I use for commuting and gravel. Walking on these are much easier as the cleats are recessed into the sole of the shoe. If the metal SPD cleat is scraping against the ground, then likely you have SPD-SL shoes that are SPD compatible, but not recessed. The SPD is easier to clip into, which is an advantage when on single track or snow. They also wear better than SL's, because they are metal and not plastic. I've yet to wear through a set of SPD cleats, but have gone through a few sets of SLs already.

To me there is no difference in terms of performance. They both fine for their intended purpose. I've been dropped many times on group rides, but I've never blamed it on my pedals.

Bald Paul

After riding with SPD-SL pedals for years, I switched over to Wahoo Speedplays. Dual sided entry, the easiest clip in / out I've experienced, and adjustable float in the cleat. My SPD-SLs are now on my dedicated Zwifting setup.
p.s.: if you really need to walk any distance in SPD-SL cleats, get a set of these:
Amazon.com : Shimano SM-SH45 SPD-SL Cleat Covers : Bike Cleat Covers : Sports & Outdoors

mstateglfr 

Ive used SL and walked away wondering why I would feel I need that for how I ride. I either ride hard solo(typically road and gravel mixed) and ride road with teens. I dont feel at a disadvantage on SPD compared to SL, but it make be in part to my SPD shoes being stiff enough to be comfortable for distance and hard power(thats relative).
I walk in my shoes a good bit before/after the group road rides and much prefer the SPD setup for that.

Like most things in cycling, there is no right or wrong way and what is 'best' is whatever works for each of us.

easyupbug 

I am with mstateglfr on the importance of good shoes with SPDs, Many years ago I go my first Sidi MTB shoes and it became clear I did not need SLs.

BFisher

I tried Look Keos first, and enjoyed them. For the heck of it I picked up a pair of M520 SPD pedals and cleats. I have come to prefer the SPD system and it is mostly due to the dual-sided option. I have a slight preference for the SPD engagement, but the Look system was also nice. I could really ride either comfortably. Both are good and it is nice to have options. The weight differences between the two pedals types don't matter to me.

PeteHski

I never really got on with SPD for mtb. Hated the vague and slip prone engagement. Always preferred eggbeaters or flat pedals for off-road. But I find SPD-SL great for road use. Walking in the cleats is not such a big issue for the little I do. I like the positive engagement and large platform. It's just a really well sorted pedal system.

Overdraft

Nice writeup yaw , thanks!
I'm less of a road warrior and more of a coffee shop warrior so I was looking for a road-ish looking solution that allowed free movement across terrazzo tile on the trip to the barista.
I ended up with Shimano es600 single sided spd which looked the part with my Ultegra groupset and xc300 shoes which as near as I can tell are just the rc3 road shoes with an actual walking surface.
Initially I was worried that I'd have trouble clipping into the single sided pedals because that's what I'd read online (to yaw 's point about what you read online), but it was no different that the SL style pedals I was riding back when I fell out of the sport 20 odd years ago, and in fact I feel like the lugs on the shoes actually guide me on to the cleats more easily than my old mountain bike spd's.

79pmooney

I have a very specific issue with my knees that drives the pedals and cleats I use. I must have forced toe-in of my feet. (I have CP - chondromalacia patellae; a lifelong issue.) Long after clipless came about I kept using my traditional slotted cleats on quill pedals like I raced on in the '70s because they worked and my knees were happy. (Every time I asked about clipless in bike stores, the salesman would say to the effect of "knee issues? Gotta have float". Finally in the early '00s, a salesman said that there were zero float cleats. Black cleats for the LOOK Delta pedals. Being cash strapped, I bought the cleats and Delta compatible pedals at Performance. "Yeah!" Now I could dial in the toe-in just like the traditional cleats. Knees loved them.

In recent years I did start using SPD mountain shoes and winter boots on a bike set up for gravel and city riding. Cranked the toe-in to full on. They work, sorta. I don't do very many long rides on that bike.

Walking - Yes the SPDs allow a pretty normal footstep but shoe wear is real and once worn, those cleats are floor killers at all places where the owners have installed nice ones. The Deltas? $15 Kool Covers are easy to put on, make walking far less treacherous and the shoes kind to floors bar the black rubber marks that wash off. I hang my Kool Kovers with an REI keyring caribiner from my seat rail. Dorky, yes. Practical, yes. And I never see it while riding. (My first several years I put them in my jersey pocket but got tired of dirty jersey pockets.)

I believe Wellgo is still making the LOOK compatible pedals. Good pedals but not great. I replace them while they are still working fine or at the first sign of issues with cleat mechanism because I never want them to fail on me and release accidentally and cause a crash. I've fulfilled my quota. Their cleats appear to be the same quality as LOOK, just minus a bell, whistle or two. I use the two interchangeably. Never saw a reason to upgrade to SPD-SL or Keo because I see no advantage other than a small weight difference and level of snazz. Not as long as I can still get black cleats. I have several more new pedal sets.

Edit: for city shoes (both SPD and traditional slotted) I build up around the cleat (or have a cobble do the work) with rubber sole material. Add a small heel. And get good walking shoes that ride without compromise. (The super glue for soles is 3M 5200. Comes in white or black. Expensive, esp the black Easy to use, messy to clean up. (Soap barely touches it. Best solvents are the epoxy and lacquer ones. Once open you have about 3 days to use the tube. Fulls gaps really well. Used to seal fiberglass sailboat decks to the hull. You can remove the bolts and pick the boat up by the deck. (Well, on a keelboat, the fiberglass will delaminate.) The shoe sole will not peel off so plan accordingly. This isn't what cobbers use. They also have good stuff but I don't know what.)

And more shoe sole fun - I now bolster whatever is on the right shoe with 1/4" rubber around the cleat because I lift that cleat off the shoe bottom with a 1/4" aluminum plate bent to fit the shoe. (Right leg came from the factory 1/2" short. I use 1/2" heel lifts in all my right shoes and half that thickness for right cleats. Got to look down the plane of the bike frame for the first time ever when I started using those shims.)

surak

I won't choose to use anything but road clipless for road riding (my PowerTap pedals use Look Keo style cleats). I prefer the engagement, don't mind walking in them, and also don't have to worry about the pedal taking a chunk out of my leg should I wipe out, as I did once when I started out on SPDs.

On other bikes I reluctantly use SPDs, which I never particularly liked. The only benefit to SPDs for me is that SPD-compatible shoes seem to allow consistently further rearward cleat placement. Had to buy midfoot-cycling cleat adapters because my Fizik 3-bolt interface boots were literally an inch further forward than where I wanted. Meanwhile the pair of Fizik gravel shoes I own have the plate in just about the same position as all my other shoes.

Psimet2001 

Having done this since the days of clips and straps I am not comfortable on a road bike without using a road pedal setup. Even with tight fitting cleat setups the 2-bolt style pedals have way to esoteric of an engagement and way too much float for me for road riding.

I have ridden:
Look
Time
Speedplay X
Speedplay Zero
Look Keo
SPD-SL
systems on the road

In 2-bolt cleat systems I have ridden:
SPD and clones
Crank Bros
Time ATAC

I currently ride (on like 10 different bikes) SPD-SL on 3 bolt systems and Time ATAC on 2-bolt systems.

I sell almost all systems. I find discussing the differences it like discussing saddle fit - everyone is different and my input outside of platform durability, weight and cost is meaningless.

I really don't care what anyone else rides.

Overdraft

and yet here you are posting...

kingston 

I use the shimano single-sided spd pedals for randonneuring because you have to walk around a lot on brevets. 2-hole shoes are a lot easier to walk in and not that much worse for low-power endurance pedaling. I use look keo for pretty much everything else. If I only had one system it would probably be spd, but that's only because I do a lot of randonneuring.

Polaris OBark

First of all, I wanted to say that is one of the most well-written, informative and organized posts I have read on Bikeforums. So thanks for taking the time.

I've used 2-bolt cleats since they first came out. Before that, I briefly had 3-bolt Shimano copies of Look. I naively thought the 2-bolt were simply an alternative design; for many years I did not realized they were designed for mountain biking. I have no recollection of what the 3-bolt ones felt like. You have inspired me to give it another try at some point.

deacon mark

I agree a great post by the original poster. Much my experience. I started with SPD and used eggbeaters for the 4 position entry. I liked them ok at first but two things happened that I gave up on them and tried SPD-SL. The eggbeaters only lasted about a year the the bearings or axel of the pedal would go bad. You can buy replacements but just about a cheap to buy new pedals. The only thing good about them looking back was the 4 sided entry was very easy to clip in.

Then I went to Shimano 105 about 6 years ago and guess what? I still am riding on the same pedals with zero maintenance. The cleats do wear but they can be changed and last me a long time. Walking in them is fine for short stuff and I don't stop and go in places or even stop to eat at a restaurant. So first great thing is they last and are way better value. The second reason and the most important is I feel much better with the wide base of support and I don't like much float. If the eggbeaters got wet from rain they would slide a bit on the pedals. I could not take that at all. The SPD-SL s just feel much more secure. The only real downside is not as easy to clip in even all the riding I do I have to make sure with purpose as I clip in. Once in the feeling of the cranks and pedals way offsets the issue related to clipping in fast.

Psimet2001 

hmmm...
I did as the OP asked. Posting about experience and not necessarily advocating for any of the options experienced is not caring what anyone else rides. It's simply providing experience.

MoAlpha

I use both and prefer SPD-SL because of the tight, secure, feel and because of the incessant and incurable squeaking and creaking of my 2-bolt system.

mstateglfr 

Ha, this reminded me that about 18mo ago I had some creaking in the shoe/pedal interface for SPD that I could not fix. It was infuriating for like 2 weeks. I removed the cleats and reattached them. I oiled the cleats. I oiled the pedal mechanism. I wd40d the pedal mechanism. I took a candle and rubbed wax over the cleat and pedal- none of that worked.
I dont think I ever did anything to fix it, now that I am thinking about the issue. It just fixed itself?...huh. Memory is a frustrating and funny thing.

surak

Another reason I like road style cleats are that they have more bike fit adjustment options. I've been fitted with both shims and wedges. Since I can't use them with my SPD shoes, I'm not nearly as comfortable on extended rides wearing them. Maybe there are equivalents for SPDs, but my fitter told me there weren't any good ones.

tempocyclist

I went from SPD to SPD-SL (well, Look KEO) and noticed pretty much zero difference when actually riding. Similar shoes too (Shimano XC7 to RC7).

Off the bike, the road cleat shoes are a little more difficult to walk in, but I don't walk much in them.


Café floors tend to be the slipperiest. 😉

indyfabz

SPD-SL on the road bike. SPD for touring and commuting, which involves a lot more feet time on the ground. (They are recessed.) The right tool for the job.

Chuck M 

I forgot all about the intermittent squeaks. Mine came and went and drove me crazy. They had to be terrible too because I am very hard of hearing and I could hear the squeaks without my hearing aids.

yaw

Some really good additions and nuances in the comments. I think it is safe to say that both systems can actually work for a wide overlap of applications. It's probably at the extreme ends of usage (e.g., road race vs. city commuting/errand running) where either system starts to shine on its own. For the leisure/fitness/cafe road riders, it's more of a slight preference and priority decision. It's good to have that choice to suit our needs, there is no 'better overall' and the differences are arguably a bit smaller than a newcomer may expect based on reading up on differences for the sake of pointing out differences. As someone who rides near daily with no set destination, hills on the weekend, and the odd gran frondo, I simply should not have gone SPD based on unfounded concerns, that is all.

That said, it is clear that shoes seem very important, regardless of the system, but perhaps a little bit more with SPD given the smaller cleat. I think it's a good idea to spend as much as feasible on foot comfort and sole stiffness, it is simply too crucial of a contact point to cheap out on that interface. I had Shimano XC501s for SPD and switched to Bontrager XXX for SPD-SL, both with arch support insoles and bike fitted cleat positions. Both shoes worked great in that the pedal interface when riding was never top of mind, which is always a good sign. Things you overly notice are often in need of further tuning. The XXX is the better shoe due to the full carbon sole at double the stiffness and bi-directional BOAs which are a great upgrade that allows for easier mid-ride adjustments without popping out the BOA - better be for over twice the price. I do appreciate the new setup when working hard up hills or really putting power down, it is a matter of those slight differences falling into place to make the pedal interface ever so slightly more suitable to my riding. I could totally see myself having both systems, as some here have, if I had more bikes to cater for different riding scenarios.