A few thoughts from my experience using SPD, SPD-SL, Look and Speedplay pedals and shoes.
Clipless pedals
From an biomechanical viewpoint, a low stack height is likely more efficient for force transfer from the legs to the pedals, one reason being that it will require less force to stabilize the foot while pedaling. From a bike fitting perspective, a cleat that is easier and more systematic to adjust will make it easier to find the best cleat position. Both conditions are best met by Speedplay pedals, especially with 4-hole shoes (for low stack height without using 3-hole to 4-hole adapters), and with it’s independent lateral and longitudinal adjustments and independent inside and outside float limiter screws.
An unpredicted merit of the Speedplays that I experienced was their smooth float which almost feels like zero friction. Though this would seem to require additional muscle force to stabilize the ankles against unwanted rotation, what I noticed was that I was actually applying more unneeded force with other pedals and using Speedplays helped me find a different, more relaxed and probably more efficient pedaling style. The conventional Speedplay cleats are bare metal and extremely slippery, but there are also some newer “aero” cleats that claim to be walkable. Also note that Speedplay cleats can collect and block with dirt; covers are recommended when walking.
SPD cleats are least slippery as they fit in the center surrounded by sole rubber. In order to really be comfortably walkable, the soles should – unless you are fine with the hard soles of trekking boots – flex at least upwards (like a “U”) but not in the other direction (which would reduce downward energy transfer). Pearl Izumi’s X-Project MTB shoes were the only ones I could find so far that met this condition.
The other pedals – SPD-SL, Look – I found similar in ergonomics. Also note that in situations and for some kind of pedaling practice, platform pedals can be more useful than clipless pedals.
Cleat holes
I have just slightly longer toes, which requires choosing slightly larger off-the-shelf shoes than otherwise needed. If the cleat holes don’t reach far enough back, the cleats will be too forward, putting too much strain on the calves just to stabilize the foot angle during pedaling. Some manufacturers (like Shimano) have holes that reach far enough backwards, some (like Northwave and Pearl Izumi) don’t. (Some people argue that for constant, lower cadence pedaling, mounting the cleats backwards in the center of the feet is more efficient.)
At some time in the future I will probably get completely custom made-to-order shoes. Until then I will have to continue drilling my own cleat holes. Shimano SPD-SL and Look have long holes in the cleats and only require round holes for the soles, which are easy enough to drill. SPD cleats adjust only sideways and require long holes for longitudinal adjustment; at least they require only two holes which are close-by. Speedplay has some extenders that allow more adjustment than their regular 3-hole to 4-hole adapters, but using adapters increases stack height. If you don’t want to use adapters, they will require a lot of holes to be drilled that are also farer away and therefore more difficult to place exactly right, and, in order to be adjustable, all those holes need to be long holes. In this aspect, Speedplay can be a nightmare.
Closures
The Northwave S.L.W wire dial system is nice as it can also be loosened in single steps. The more common B.O.A wire dial system can only be unlocked. Ratchets can be loosened while riding but often not in single steps. All of them are easier to adjust exactly than velcros though it may be debatable whether they are worth their cost.
Insoles
I tried a lot of shoes and the heat-molding Shimano insoles (and shoe upper parts) have been unbeatable. If my feet were closer to what shoe makers think is average, I’d probably not need these. If I had some knee issues etc this would probably not be enough and I’d need to ask a professional to get some customized insoles
Pedal reflectors
It seems most roadies prefer being killed than adding pedal reflectors to their bikes. Shimano has optional reflectors for most of their pedals. Northwave has some shoes which are really reflective.
Pedal-based power meters
Garmin’s Vector 2 can be fitted into Shimano Ultegra pedals. They have a pod hanging on one side of the cranks that could be damaged during transport or off-road, less so on-road. Some of their advanced metrics and the way they visualize the data on their Garmin Edge computers are not very useful, but I find at least torque efficiency to be useful when adjusting my position. The Powertap P1, while convenient to swap between bikes, have so much stack height that I have to adjust saddle height and change my pedaling style and are not user serviceable meaning they have to be send back for maintenance which is costly and will leave you without your power meter. Their refreshed iOS apps visualizes some of their pedaling analysis but is not very legible. The P1 might be the only current pedal meter that could visualize or record foot angle – at some time in the future.
Combinations I currently use
- Shimano RP-9 for use with Garmin Vector 2 power meter fitted to Ultegra pedals
Somewhat boring combination but fits well and reflectors make me more visible at night. Downsides: Pods. Not walkable.
- Shimano SH-R320 with Look cleats for use with Powertap P1 power meter pedals
Easy to attach to rental bikes to get power data. Downside of this combination: a lot of stack height, no reflectors, power meter transmission unreliable when riding on trainers in hotel rooms that have a lot of wifi interference.
- Pearl Izumi X-Project 2.0 shoes with Shimano SPD cleats and Shimano MTB pedals
Good: relatively comfortable to walk in. SPD pedals can be fitted with reflectors, although that makes them single sided. Best for touring when you also need to walk. Downsides: Cleats available only with 6 degree float – would love zero float for these. Can be difficult to release when climbing at extremely low cadence, though this might just be me. Pearl Izumi cleat holes don’t reach back enough.
- Speedplay zero with Northwave 4 hole-compatible shoes
Good: shoes are really reflective. The Downsides: Drilling that many cleat holes can be a pain (if the original ones don’t fit).
Future plans
A few years ago I tried Bont shoes at a shop but without molding them and they didn’t convince me then but I might try them again as their form might better fit longer toes and they have heat moldable soles and uppers. Beyond that, semi or full custom shoes made using molds of your feet can be had from Bont, Rocket7 or Riivo and cost somewhere between USD1000 and USD1500. Anyone with experience in those? Other than that, with all the 3D scanning and printing technologies being developed now, fully custom might get a lot cheaper in the near future.