Smart turbo trainers these days can do a lot of things. But at the end of the day, some people are just looking for something that connects to Zwift and gives you a way to do some indoor training when it’s raining.
That describes me pretty well.
I was using a wheel-on trainer with a speed sensor and cadence sensor. It was okay, but I had no way of knowing how much power I was really producing.
That was, at least, what I was looking for when I bought a Tacx Flux 2 Smart.
Things to consider before buying the Tacx Flux 2 Smart

Trainers can come with a lot of extras.
These can include a huge amount of power, the ability to change gradient, or even cobblestone simulation. But the most important things are a lot simpler than that.
Connectivity
Most small trainers will connect with ANT+ or Bluetooth. It is worth thinking about what will be connected to the trainer. For example, it could be a phone. It could be your computer.
With the phone, he would need a Bluetooth connection. With the computer, you would probably need to get an ANT+ dongle. In terms of Bluetooth, some trainers only accept single connections. So remain aware of that.
Direct Drive
Direct drive is a prerequisite for any smart trainer. It allows you to change speed or resistance incrementally and therefore substitute the road feel.
Also, it worth checking out what wheels you can run. If you’re into mountain bikes then a 29er might be an issue with some trainers. That said this one can handle it.
Response
If you use Zwift, you will need something that can react to the changes in pace and gradient. This will mean the difference between bouncing back and forth in the pack and losing the draft.
Accuracy
Accurate power measurement is one of those things that a lot of reviews go to a lot of detail, but unless you are training for the turn France there’s no point splitting hairs on this. That is controversial, I know, but what does a watt matter here or there?
Gradient
The amount of gradient that the trainer can simulate can matter. Most of the climbs in Zwift don’t get much steeper than 18%. But if you do end up climbing that kind of gradient, you want to be sure that it is accurately represented.
Who is the Tacx Flux 2 Smart for?
The ideal customer for this product is someone who wants to get on and ride without any problems. It is safely within the mid-range, perhaps even if not the higher end. But it is not necessarily for the person who wants to go racing on Zwift.
The original Tacx Flux pretty much defined the mid-market direct drive trainer when it came out in 2016. This led to several other manufacturers such as Elite and Wahoo adding their own. The Flux 2 came out in 2018 alongside the Flux S – this letter trainer is effectively a rebadged version of the original Flux.
One thing to note is that this review is for the original Tacx flux 2, not the Flux 2.1, which launched last year.
Pros and Cons
- It's seriously durable.
- Great for the money.
- Plenty of power at 2000 W
- 16% gradient will cover most climbs
- Accuracy could be better.
- It takes up space and is not foldable
Unboxing the trainer
The Tacx Flow Smart. The first thing you notice about it is it is pretty heavy. Like a lot of direct drive trainers, it is not designed to be moved around. So a quick suggestion is to try and move the box close to where you will set it up.
Inside the box, the trainer is in two parts: the stand and the trainer itself. It also comes with a quick release skewer and plugs. As well as manuals. There is also a voucher for Tacx’s own training app.
It’s pretty easy to bolt together.
One thing it does not come with is a cassette. This is a direct drive trainer; the back wheel is removed and placed onto the trailer, so the cassette is actually on the trainer itself. You will need to supply your own and be able to fit it to the trainer.
Most cyclists will have the equipment needed – a chain whip, lockring, and a spanner – to change a cassette on the bike. I am personally not very good at bike maintenance, but even I know how to do this.
However, not everybody is going to be able to. To be fair to Tacx, many of the trainer manufacturers do not supply a cassette. The reason for this is that it really depends on what you’re gearing is. Some people may have 11 gears, some may have 10 or even 8, which can affect your cassette. And then there Campagnolo/ Shimano/ SRAM to consider.
Features and Benefits
The direct drive mechanism operates with magnets, so it can change speed incrementally rather than like you would get with a cheaper trainer.
Allows third-party apps to control the trainer
It can connect with all popular training apps and connects via Bluetooth Smart as well as ANT+ FE-C. So it can hitch up with any smartphone, tablet, or computer.
I used Zwift, The Sufferfest, Trainerroad, and the Big Ring VR, among others. All of these have worked fine with both ANT+ and Bluetooth.
Apart from Big Ring VR – which I found a bit bothersome in set up – it was simply a case of turning on the trainer and allowing it to be picked up from the app.
I’d say the only times I’ve ever had problems connecting were the fault of the device/ wifi/ Bluetooth interference and not the trainer (if you’ve come up against this, check out the connection section in the 107 Indoor Cycling Tips guide).
A heavier flywheel for a smooth ride

The trainer uses a 7.6kg heavy flywheel. As a result, there are quite 8 permanent magnets, and replicates road feel pretty well. Although to be honest – I doubt any trainer really manages this.
The Flux 2 has a maximum power resistance of 2,000 watts at 40 km/h and can simulate a 16% grade. This is easily good enough for most of the steep hills you will find on Zwift. However, if you’re finding it easy to go up a 20% local hill in Fulgaz – you now know why.
Display – 2 LED lights
One thing I always found a little strange with the tax flux is that there isn’t much in the display. There are just two or three LED lights that show that it is switched on and connected to an app.
Maybe it’s just me, but I also found – and still find –it quite weird that there isn’t any other way of turning off the trainer other than switching off the mains.
Accuracy – not bad but could be better
The trainer is accurate to around 2.5%. Now, while I said above that isn’t such a big issue. But if you are on Trainerroad, it might have more of an impact.
However, it could well be an issue for those who are tracking their output more closely. For example, both the Elite Direto and the Saris H3 are more accurate with 1.5% and 2%, respectively.
Noise Levels – will it annoy the neighbors
Okay, I haven’t been sad enough to get a decibel tester. I can say that the trainer makes far less noise than the wheel-on the magnetic trainer that I used. I would go so far as to say the loudest noise is my heavy breathing as I’m trying to keep up with the bunch.
If you put this upstairs or in a flat with wooden floorboards, you had better make sure you get a thick rubber mat. That is the same for most smart trainers anyway. In short, this trainer keeps noise to the absolute minimum.
Response – drafting can be hard
My biggest bugbear is the ability to follow other riders on Zwift. When I’m riding within a big group it’s possible to hold onto them although you’ll find yourself moving up and down without changing much speed. If there’s a surge I suddenly have to sprint for a bit to come off the back and 5 seconds later be on my own at the front.
However, it’s impossible to draft behind one or two riders. You either go too fast or too slow. The ability to hold a steady pace is tricky – even when it’s been calibrated.
Where it fits in the market
The Tacx Flux 2 Smart fits snugly within the midmarket. However, considering all of the smart trainers out there, including the ones that are wheel-on, it is probably one of the cheaper direct drive trainers on the market.
Other similar machines in the price range are the Sarris H3, the Elite Direto, and the Wahoo Kickr Core.
How to get the Tacx Flux 2 and some alternatives
- The flux 2 smart is equipped with a stronger resistance unit and a heavier flywheel to increase the
- By supplying the flux 2 smart with extra axle adapters, the axle compatibility significantly increas
- The internal mechanics of the flux 2 are redesigned to improve the ride feel and the power measureme
- Intuitive leds on the side of the flux 2 smart show when the trainer is powered and connected to a d
- With the tacx utility app you can easily update the firmware of the flux 2 smart to the latest versi
- Folding legs for easy transport and storage
- Adjustable, non-marring feet hold the bike steady while protecting flooring from damange
- Sensor-free cadence measurement
- Compatible with qr, and 142mm thru-axle frames. adaptor available for 148mm frames
- Shimano compatible freehub body
- Quieter than ever: all new drive system shaves decibels off previous generations. noise level: 59 de
- Precise training: +/- 2% accuracy
- Controlled & consistent: electromagnetic resistance provides a measured workout every time
- Connectivity: connects to indoor cycling apps with dual ant+ fe-c and bluetooth ftms standards. zwif
- Compatibility: thru-axle compatible for rear hub widths of 142 mm or 148 mm. quick-release compatibl
- Features: folding legs, carrying handle, built in front wheel block, and cooling system that moves a
Conclusion
The Flux 2 is a great smart bike trainer for anyone who wants a direct drive trainer without any hassle or gimmicks. However, it lacks some of the advanced features found on some other newer trainers.
Speak about this one personally. I’ve used it as my trainer of choice for the last couple of years, and it has run like a dream. Moreover, as you can see from the pics, I’ve given it an absolute hammering and it still works like the first day I got it.
Yes, I have also tried some of the more expensive ones like the Tacx Neo. But this does the job pretty well if you want to use it for indoor training and a fair amount of interactivity with third-party apps.
Sure, you could spend more money on a better trainer. But ultimately, we are doing this to get fit and become stronger cyclists outdoors. So spend the extra money on the bike.