The clever smart trainer mod that’s helping a four-year-old ride Zwift

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Chances are good that the current coronavirus-related stay-at-home mandates are making you more than a little stir crazy. You might not be allowed to ride outside, depending on where you are, and even if you’re fortunate enough to have that freedom, you’re really not supposed to be riding with people you don’t live with. You’re not able to meet with friends at bars and restaurants for happy hours and casual dinners, your frivolous shopping trips are on hold, and so on, and so on.

So what are we all to do then? It doesn’t take a lot of sleuthing on social media to see that people are suddenly adopting all sorts of hobbies. Baking. Knitting. Gardening. Cooking in general. Maybe finally picking up that second (third? Fourth?) language. And certainly it’s time to tackle those home projects you’d been putting off.

If you have kids, though, it’s been a different story.

That was the situation confronting Eric Filcoff, a graphic designer in Cary, North Carolina, and his wife, Jeni. They’ve thankfully been able to work from home, and Filcoff still has his own outlet to work through some stress. His bike is set up on a STAC smart trainer, and a folding table is stationed with his laptop on top so he can connect to Zwift.

The Filcoffs also have two children. Ollie is four, and his baby sister is five months old.

“It’s going as well as I’m sure everyone else is going,” Eric Filcoff said. “There’s the struggles with trying to keep kids occupied and trying to do some semblance of education, but not succeeding. [The constant feeling of failing] is lovely.”

Ollie kept wondering why dad kept disappearing into the garage every now and then. More perplexing was why dad was sitting on a bike and feverishly pedaling nowhere.

“He was interested in why I was sitting in the garage looking at the computer and riding at my bike, not going outside — that whole concept,” he said. “I was like, yeah, I know, I don’t really get it either but it’s what we do these days. ‘Why are you looking at a computer? That’s what you do when you work.’”

For any four-year-old, that sight would indeed be confusing. But for a four-year-old that’s been stuck inside for the past few weeks, it seemed like potentially a good way to blow off some steam (or, at least, that’s how dad was looking at it).

The STAC Zero Halcyon — now known as the 4iiii Fliiiight after the company bought it in May of last year — is a unique wheel-on stationary trainer design in that it doesn’t contact the wheel or drivetrain at all. Instead, it positions two electromagnets on either side of the rim, and the system can change the resistance by altering the current sent through the magnets.

It’s incredibly quiet as a result, but it also doesn’t work with carbon wheels. But hey, what four-year-old has carbon wheels on their bike, right? I mean, you have to draw the line somewhere.

And so in a rather brilliant two-birds-with-one-stone solution, Filcoff made a quick little modification with some bits of lumber and a few wood screws, and Ollie was in business.

And holy crap, it worked.

Filcoff is apparently pretty handy with a saw and drill. This trainer wasn’t originally meant to be paired with a 16″ wheel (and you can still see how the curve of the magnets doesn’t match the rim), but desperate times call for desperate measures.

“The trainer itself is a bit of a homemade thing, anyway, and I was looking at it, and it was pretty clear that you could raise up the resistance units with something longer, so that’s what I did,” Filcoff explained. “Using a piece of metal would have been been better, but a little bit of 1×2 pine did the trick.

“So I just figured I’d get him on there so he could learn to pedal. He loved it. At first, I just had him in the stand without the resistance unit on. He would use the Just Watch function on Zwift, choose someone, and just watch them ride. He was loving that. I asked him if he wanted to try and ride it himself and make his own bike move, and he was like, ‘yup’.”

One of the draws of Zwift is that it’s a gamified version of real-world cycling, which would obviously be especially appealing to someone Ollie’s age. Granted, Zwift has yet to heed CyclingTips’ repeated calls to turn the environment into some two-wheeled hybrid of bicycle racing and Mario Kart, but that doesn’t seem to have deterred Ollie too much.

According to Filcoff, Ollie has been hopping on Zwift fairly regularly since he cooked up the hack, lasting as long as 25 minutes to date, completely of his own accord. And as any parent of a kid that age would know, that’s nothing short of a miracle.

“He just kept on going,” Filcoff said. “He wanted the timer set up and the fan on, just like his dad — and all the other people just sitting in the garage riding their bikes right now.”

Eye of the tiger.

All is not perfect, though. Given the much-smaller-than-normal wheel, Filcoff is having issues getting the slower rotational speed to play well with both the STAC resistance unit and Zwift’s simulated speed and power algorithms. And unfortunately, Ollie doesn’t have the patience to keep pedaling while dad tries to figure out the bugs.

“It doesn’t work very well, to be honest,” Filcoff lamented. “The wheel speed isn’t quite there to get the watts up and get him to move very quickly. I haven’t quite cracked that yet, but we’re working on it. Currently, he’s back to just pedaling and watching. But he’s all about it. He actually just asked me today to put his bike on.”

Hey, 4iiii, if one of your engineers would like to lend a land, I dare say we might be able to put the two of you in touch. There’s a four-year-old (and two desperate parents) out in North Carolina that would be very appreciative.

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