Tacx Flow Smart review

The Tacx Flow Smart is a budget wheel-on smart trainer that offers one of the cheapest entry points into interactive indoor cycling.

It has a modest spec and basic design but comes from a brand with a strong reputation for producing top-performing smart trainers.

In an age when pricier direct-drive smart trainers take most of the plaudits, can this value option compete? In short, yes, it can.

While it doesn’t offer the same luxuriously realistic ride feel or all-encompassing specifications of the very best smart trainers, the Tacx Flow Smart is a great entry-level option.

Tacx Flow Smart setup

Appropriately for an entry-level trainer, the Flow Smart is very easy to assemble and set up. Once out of the box, all that’s required is to attach the resistance unit to the support legs, fold out the legs, plug it in and you’re good to go.

There are two sets of holes on the legs, each designed to place the resistance unit at the right angle for your bike. If you’re using a road bike with standard 700c wheels, as I am (or a mountain bike with 29in wheels), then you’ll attach the resistance unit to the upper set of holes.

It’s worth noting the Flow Smart doesn’t ship with thru-axle adaptors, only a 130mm quick-release skewer. If your bike uses thru-axles (a likely scenario if your bike has disc brakes), then, you may need to fork out an extra £25.99 / £34.99 (depending on exactly what type of thru-axle your bike uses) for one.

A front wheel riser block is included in the box, though. This helps level the bike out and stops the front wheel from moving around too much while riding. It’s a great inclusion at this price point.

At the rear of the resistance unit, the height of the roller can be adjusted to fine-tune the force with which the roller contacts your rear wheel. I’ll talk more about this later because getting this bit right is critical to calibrating the Flow Smart’s internal power meter, but at this point, you just want a firm contact between the roller and the tyre.

As with any wheel-on trainer, you can opt for a turbo trainer-specific tyre, but a hard-compound or winter road bike tyre, pumped up to a high tyre pressure (Tacx recommends 6-8 bar / 87-116psi), will do a similarly good job in my experience.

However, if you have delicate road bike tyres designed for racing, it’s probably not a good idea to use those on a long-term basis. The soft-compound rubber will wear more quickly and they’re likely to be more expensive to replace.

Once you’ve finished your ride, the Flow Smart folds away for storage and is compact. At just 8.49kg, it’s easy to carry and move around, too. This is great if you don’t have a dedicated space (sometimes referred to as a “pain cave”) to leave it set up.

Tacx Flow Smart performance

Connectivity

The Flow Smart transmits power, speed and cadence data over both ANT+ and Bluetooth.

Connecting to Zwift presented no issues, though I did have a few data dropouts when using ANT+ instead of Bluetooth.

It’s not possible to perform a spin-down calibration for the Flow Smart in Zwift, so you’ll need to use the Tacx Training app instead. This app can also be used to update the trainer’s firmware, as required.

Calibrating the Flow Smart wasn’t an entirely pain-free process. The first few times I tried it, the app simply returned an error message saying “something went wrong”, but with no indication as to what that “something” might be.

After attempting it a few more times and not making any headway, I resorted to consulting Google. My search suggested the roller contact with the tyre was either too loose or too tight, and it turned out to be the latter. Once I’d loosened it off a bit, the app was able to complete the calibration successfully.

It would be helpful if Tacx’s app could give some indication as to what might be going wrong or at least offer some suggestions about what to do to put things right.

Once you’ve completed this calibration, though, you shouldn’t need to do it again very often, providing you keep your rear tyre pumped up to the same pressure.

Ride feel

With its relatively small, 1.6kg flywheel, ride feel was the area I was expecting the Flow Smart would suffer most, especially in comparison to more expensive smart trainers.

And while it’s certainly not up there with the best, it’s more than acceptable considering what it costs.

The lightweight flywheel doesn’t generate much inertia, so accelerations and coasting don’t feel amazing, but otherwise, it’s perfectly fine.

With its low overall weight, it can’t compete with direct-drive trainers for stability – but again, that’s not really to be expected. Given its maximum power ceiling of 800 watts, the Flow Smart arguably isn’t a trainer designed for heavyweight sprinters anyway.

More powerful riders are likely to find the Flow Smart wanting for resistance and stability, but it’s also unlikely to feel limiting for beginners or riders who train indoors on a casual or occasional basis (arguably its target audience).

Likewise, though the maximum virtual gradient of only 6 per cent seems low at first glance, the default trainer difficulty setting of 50 per cent on Zwift makes this less of an issue.

With this setting left as it is, you don’t actually max out the resistance of the Flow Smart until you hit a 12 per cent gradient in Zwift.

In practice then, climbing a virtual alpine climb like Alpe du Zwift is an experience not massively dissimilar to what you get with trainers costing a lot more, and that’s impressive at this price.

In terms of noise, it’s a similar story to the Tacx Boost I reviewed last year (a non-smart wheel-on trainer with a similar construction). At steady power outputs of around 200 watts, it hovers around 68dB, which is actually pretty good.

Once you start putting out more power and cranking up the flywheel speed, though, the noise levels do progressively ramp up. The pitch of the noise it makes is also relatively high compared to direct-drive trainers I’ve tested, making it feel a little more intrusive.

This isn’t a trainer for doing sprint training in the room next to a sleeping baby, then. Still, there’s an element of “you get what you pay for” here (as I keep emphasising).

All things considered, the Flow Smart isn’t going to blow anyone away with its ride feel or noise levels, but it puts in a solid performance for its price and feature set and is actually quite impressive in that sense.

Tacx Flow Smart power accuracy

Tacx claims the Flow Smart is accurate to within +/- 5 per cent and I generally found power accuracy to be good once warmed up, with a few caveats.

When riding along at steady power outputs, the Flow Smart does an impressive job of consistently tracking on-bike power meters closely.

Cadence accuracy is also solid – something I haven’t always been able to say about some direct-drive trainers costing almost double the price of the Tacx Flow Smart.

ERG mode responsiveness is pretty good too, responding to changes in the power output prescribed by a Zwift workout relatively smoothly and quickly, and it manages to hold specific resistance levels well.

The accuracy of the power data does fall off at higher power outputs or trainer resistances, however.

This resulted in an underestimation of my power output when sprinting or attacking on flat virtual roads or in ERG mode workouts, and an overestimation of my power output when climbing consistently steep in-game gradients like Alpe du Zwift.

In those kinds of situations, accuracy was more like +/-10 per cent. Not amazing, but not terrible either. It is consistent in how it reports power too, meaning the inaccuracies don't overly affect the in-game experience.

For basic indoor riding and training (where absolute data accuracy is arguably less important than simply getting a fun, immersive experience), the Flow Smart’s data accuracy is well within the right ballpark.

Tacx Flow Smart bottom line

The smart trainer market is very competitive these days, but there are still few options if you’re shopping on a limited budget.

Fortunately, the Tacx Flow Smart offers a compelling entry-level option. Its modest spec is clearly designed to hit a price point, but it doesn’t feel overly limiting in use, even for an experienced indoor rider like myself.

Would it be my first choice given an unlimited budget? No. But if £300 or so was all I had to spend on a smart trainer, I’d be very happy with the Flow Smart.

It’s one of the cheapest ways to get a proper interactive smart trainer and, most importantly, it fulfils the promise of providing an immersive and enjoyable indoor cycling experience when paired to an indoor training app such as Zwift.