TerraTrike Comfort Pedal Conversion Kit / by Erin Wade

In a lot of ways, a recumbent trike is arguably safer than an upright, "diamond frame" (DF) style bike. The fact of having three wheels under you instead of two means that there is no need to balance, nor any of the issues that can come from failing to do so. I’ve been riding cycles for most of my life, and the majority of the injuries and mishaps I’ve experienced over the years have involved some instance of the upright not remaining so.

This is not to say that a recumbent trike is free of risk. It is possible (or, ahem, so I hear...) to roll or flip a trike, for example. But a somewhat unique risk is the one that falls under the charming description of leg suck. This is what occurs when the feet leave the pedals at speed and get caught and dragged under the seat of the trike.

I’ve been fortunate enough not to have experienced this thus far in my trike-riding tenure. Over the first couple of months this was just dumb luck - I bought my Catrike Pocket used on eBay, and so didn’t know about this phenomenon. Joining triking groups on Facebook made me aware of it, and after that it seemed reasonable to take precautions.

Catrikes come with a pretty nifty stock pedal that has a flat, platform-style regular shoe option on one side, and a fairly standard "clipless" option on the other. This offers up the option of simply getting clipless cycling footgear and snapping into the pedals. For a lot of people this is probably a pretty good option, especially if you already own cycling shoes.

I am not one of those people. My DF bike is a 1987 Cannondale SR400 (sadly, largely in disuse since I got the Catrike) with Toe Clips, the old stirrup-style cages that wrap around (but, oddly, don’t clip on to anything) the foot. As such, I’ve never purchased cycling shoes. And because I ride year-round, I’d need several different types for the different seasons, which could get spendy in a hurry.

My interim solution for this was to use cross-straps built from Velcro Thin Ties (like a Velcro tie wrap). This is two strips of Velcro put in a diagonal pattern across the pedal that I slide my foot into. When the foot turns vertical they tighten up and hold the foot in. They seemed to work ok, and at just over $10 for 100 of them, they are pretty economical - about ¢0.20 per foot. I’d love to take credit for this idea, since it seems such a simple, elegant solution, but I borrowed it from someone else in one of the triking groups (I wish I could remember who) who clearly does a better job of thinking outside the box than I do.

Now, they would periodically wear out and break, but that’s only ever happened when putting my foot in them - never when riding.

...So far.

It’s the so far part that bothered me. Maybe this solution is perfectly sustainable over the long haul, or maybe I’ve just been lucky. If the latter was true, though, it seemed reasonable to look for a different solution.

This past April I had the opportunity to swing through the Wheel and Sprocket Bike Expo in Milwaukee. I’d gone to get an opportunity to take a test ride on a Catrike Expedition (this seems like the front-running candidate for my next trike), but while I was there I looked at the other trike displays as well. TerraTrike was there, and one of their models had heel slings on the pedals. I asked the staff/salesman about these, and he indicated they are designed to bolt on to any pedal. They go by the somewhat cumbersome name of Comfort Pedal Conversion Kit. Apparently "heel slings" isn’t a jazzy enough name. But jazzy or not, they run right under $45 bucks, which is way cheaper than all but the least expensive single pair of cycling shoes on Amazon.

That was April and this is October, so it clearly took me a while to get around to ordering them. When I did so, they were out of stock on TerraTrike’s Website, but Bicycle Man had them (I may have bought their last set - it’s currently listed as sold out).

I ordered them in late August, but ran into a snag as I went to install them. These are, perhaps unsurprisingly, not designed with the standard Catrike pedals in mind. They are a pretty simple design, intended to be bolted in through the holes that the standard pedal reflectors mount to. To do this, they come with a threaded backing plate.

Backing Plates

This would work quite nicely, but the backing plate was too wide to fit into the space allowed on the Catrike pedals. So I stepped away from them, went out for a ride, and waited for a day that I would have time to sit down with a grinder and shape the plate down so it would slide in.

When that day came I was able to get it to slide in to the open space with a minimal amount of shaping. But once it slid in it was clear that the plate was also too tall for the opening - the holes didn’t line up (and it drops against the pedal on the other side). Clearing away that material would have involved a lot more grinding, and my skills in this area are limited. So, again, I stepped away, went for a ride, and thought it through a bit.

Ultimately I realized that I might be able to find nuts to secure them to the pedals instead. I stopped by the local hardware, taking the mounting bolts with me, to see if I could get a match. After a little bit of trial and error I was able to find them - they are M5.00’s. I picked up a handful of both nuts and lock washers in the appropriate size (I always get extras - makes it much less frustrating when something gets dropped and rolls away, nowhere to be found).

nuts and washers

Pedal with nuts

This worked, albeit with caveats:

  • The bolts it comes with aren’t long enough to get both the lock washers and the nuts on, so I went with the nuts alone. The bolts come with thread compound on them, so this should help hold it. I’ll need to check them periodically.
  • To get the nuts on I had to remove the Allen bolts from the outside frame of the pedal and swing it up. This meant that the plate for the heel sling covered one of the holes once it was attached, so I had to leave one of the bolts off. The outside frame is now held on by three bolts instead of four. Hopefully that will not cause any issues.

swing down pedal frame

All told, once I had all of the parts together, this took about an hour to do for both pedals. If you are more handy than I - and odds are good that you are - it will probably take you less time.

How Do They Work

Caveats aside, I got them installed and I’ve since had them out for a couple of rides. My very first impression involved trying them out for a very short ride with my typical summer riding shoes - a pair of Keen sandals. The picture on the box shows them used with sandals, so you’d think this would be ideal:

Judging a box by its cover

It... wasn’t. The way the strap falls does not go across the sandal strap as is shown in the drawing on the box. Rather, it falls across the heel, below that strap. Having the strap loose enough to get the shoe through means that it is a little loose at the heel. Yes, it is Velcro, so you could open it and close it each time, but it’s one very long, continuous piece of Velcro, so that would become a real pain in a hurry. On that initial ride, it didn’t feel as secure as I would have liked. It was fine with the cross straps (which I left on the pedals), but didn’t feel as secure when I rode for short ways without them.

foot strapped in

other foot strapped in

However, they worked quite nicely with regular shoes. In this case, I broke out my nearly pristine pair of running shoes that I purchased, oh, say, 10 or 12 years ago (turns out I love cycling and hate, hate, hate running). The straps fit perfectly over a shoe without an open back, and the extra lip of the heel holds it in. I did (and do) continue to use the cross straps, but I did ride for a short distance without them just to test them out, and the slings seemed to secure the foot (with regular shoes) quite nicely. I took them out for a 20-ish mile ride, and found them to be quite comfortable. Getting in and out of them while also using the cross straps takes some learning, but it gets easier with practice.

I also took them out for one of my most common rides with the sandals on. They still felt a little less secure, but the sensation went away after a bit. And since the strap falls at the heel, if the foot does drop out, it’s going to catch between the bottom of the foot and the sandal - it’s still in a position to keep the foot from falling off the pedal.

While they take some learning in terms of getting into and out of, they took none at all once I was riding. They technically add a bit of weight to the trike as well, I suppose. In either case, on my first two rides I actually had personal best times for both. I don’t think they improved my speeds (though I suppose I could be wrong about that), but they certainly didn’t slow me down, and they felt pretty natural after a few minutes.

Visually, they aren’t particularly sexy, but in the end, my risk of leg suck should be significantly diminished.

not sexy, but safe

TL:DR Section

The long and short of it works out like this:

  • These appear to be an economical alternative to cycling shoes, especially if one rides across multiple seasons.
  • They work better with solid-backed shoes than sandals. I will continue to use a cross strap in addition to the heel sling for all shoes, but especially the sandals.
  • They are not designed to bolt directly to the standard Catrike pedals. This is not surprising, since they are built by TerraTrike. But you can attach them with M5.00 nuts. Make sure you have some kind of thread locking compound.
  • When I put them on, it involved removing the outer bolts on the pedal frames to swing the frame up so I could attach the nuts. This resulted in the sling brackets covering one of the bolt holes, so it left me with three rather than four bolts holding on the pedal frame.
  • They take some learning to get in and out of, but riding with them comes quickly.