Tacx Flux S Smart trainer review

Stop staring at walls and start training smart

Our rating 
4.0 out of 5 star rating 4.0
GBP £549
Indoor bike trainer, Tacx Flux S Smart

Our review

The Flux S paired seamlessly with Tacx’s own app, as well as Zwift and TrainerRoad
Pros: Smooth, seamless pairing with apps; realistic ride feel
Cons: Slight lag in changing resistance when altering gradient; don’t expect total silence

Direct-drive smart trainers that talk directly to your phone, laptop or tablet and enable you to train to power and immerse yourself in virtual cycling worlds such as Zwift and Bkool have become the new standard. For those of us still wearing out the rubber of our rear tyre while staring at the garage wall and listening to a Bruce Springsteen bootleg (your musical tastes may vary) it can seem like another world. But the good news for us late adopters is that connected indoor training, and the virtual world it supports, is becoming ever-more affordable.


Enter the Tacx Flux S: while the Dutch company’s flagship Neo 2 Smart will set you back £1,200 / €1,300 / $1,400 / AU$1,900, this model offers the most necessary features for less than half that price.

It operates via a flywheel system, so noise is not entirely eliminated, but compared to most non-direct-drive turbos we’ve tried, it is impressively quiet – even when pushing hard against the maximum 10 percent gradient this Flux S can simulate.

Compared to the 25 percent incline that Neo 2 can copy, 10 percent might not seem huge, but it’s the same as Mont Ventoux so how much extra suffering do you want?

The Flux S paired seamlessly with Tacx’s own app, Zwift and TrainerRoad during my test, requiring nothing more than a tap of a touchscreen button in each case. The power readings were consistent across all three apps – Tacx claims an accuracy of +/- 3 percent – so I was happy to trust the numbers and accept that the trainer was working as it should.

The ride feel is definitely a step up from ‘wheel-on’ trainers in my experience, and there’s no doubt that feeling the resistance increase as you hit the foot of a climb on Zwift adds to the fun, regardless of the training benefit.

When using the ‘Slope’ setting in the Tacx app to increase the gradient of my session there was a lag of a few seconds before the extra resistance kicked in, but this was less noticeable in the ‘game’ atmosphere of Zwift. Other trainers can replicate the feel of riding over the cobbles but, even if it lessens the realism slightly, I didn’t miss that.

Tacx Flux S Smart trainer details

Tacx Flux S Smart indoor trainer with three arrows named: 1. Cassette, 2. Resistance, 3. Intelligent
The ride feel is definitely a step up from ‘wheel-on’ trainers in my experience
David Caudery/Immediate Media

1 – Cassettes: Shimano and SRAM 8-11 speed cassettes fit directly, while a Campag body is sold separately.

2 – Resistance: The Flux S uses a magnetic field to create resistance, and this can be altered to make riding harder.

3 – Intelligent: The Flux S talks directly to your phone/computer, giving easy access to speed, power and cadence data.


Tacx Flux S Smart specifications

  • Trainer type: Interactive Smart direct drive with electric brake
  • Magnets: 8 permanent ferrite magnets and 8 electromagnets
  • Suitable cassettes: Shimano and SRAM 8-11 speed; Campagnolo body sold separately
  • Weight: 22.8kg
  • Footprint: 670 x 642mm
  • Height: 460mm
  • Max incline: 10%
  • Max torque: 22.1Nm
  • Max brake force: 65N
  • Foldable: No
  • Price: £549 / $749 / AU$1,050