Smart trainers have transformed indoor riding for the better over the past few years but the new technology has brought along some irritations and problems of its own. Here are some of the issues that have bugged us recently...
It's usually not cheap
Smart trainers don't tend to be cheap. Okay, something like the Tacx Flow Smart trainer is £269.99 but you're generally looking at quite a bit more than that. A Wahoo Kickr is £999.99, for example, and a Tacx Neo 2 is £1,099.99.
Read our review of the Wahoo Kickr smart trainer
To ride on Zwift you'll also need a PC or Mac computer, a compatible iOS device (such as a tablet), or an AppleTV, but the chances are that you already own a capable device. You might need a receiver for the ANT+/Bluetooth LE signal too and, although not required, you can use a cadence sensor.
On top of that, there's the cost of a subscription to any indoor cycling platforms that you want to use. Zwift, for instance, is £12.99 per month.
Assuming your goal is to get fitter, you might be better off spending that money on employing the services of a coach or heading off on a training break.
Check out three Zwift setups to suit every budget
On the flip side, smart training through the winter might save you money on expensive weatherproof clothing and lights, so it's not all one-way traffic.
Do you need it?
While we're talking about the cost, it's worth bearing in mind that you don't need a smart trainer to ride on Zwift. A smart trainer transmits your power data and can change the resistance so you can feel virtual hills, but you can use a supported classic trainer and a speed sensor instead. You won't get changes in resistance but Zwift will calculate your power based on the speed of your rear wheel.
Check out 11 of the best smart home trainers
If you already own an ANT+/Bluetooth power meter you can use it with any trainer/rollers to ride Zwift.
Find out how to get started on Zwift
People cheat!
Say you weigh 75kg and you're putting out 250 watts on Zwift... then you go in and alter your weight to 65kg so your power-to-weight ratio increases significantly. This is weight doping and it's very naughty, but people do it.
Check out all of our indoor trainer reviews
This doesn't really matter if you're not taking it too seriously, but just bear in mind that you sometimes have to take the results with a pinch of salt.
Accuracy is sometimes suspect!
Some people have smart trainers or power meters that read high or low, perhaps because they've not been setup or calibrated correctly. That's another reason not to take online racing too seriously.
Connectivity issues
Tech can sometimes be frustrating, especially tech that you can't see like ANT+ and Bluetooth connectivity.
You might occasionally find that a smart trainer app doesn't connect with your trainer. This might be because your trainer is connected to another app via Bluetooth – to the Wahoo Fitness app, for example, following calibration – so you'll need to disconnect it.
If you're using an ANT+ key/dongle, make sure that it's being used for only one program or you could have problems with TrainerRoad or Zwift.
One little trick you can try if your app and bike trainer aren't connecting is to switch off your trainer and wait for a few seconds. Then open the pairing menu in your app and have it start searching, and only then switch your bike trainer back on. 
You might also find that the signal drops out during use. There can be multiple reasons for this, including interference from an HDMI cable, but if you're using a speed sensor we've found that one of the most common causes is that the battery is running out of juice causing its range to drop.
Not all 'smart' trainers can be controlled by Zwift
There are different types of trainers that are described as 'smart', so make sure you know exactly what you're buying.
The resistance unit of a smart trainer can transmit your speed wirelessly to another device such as a laptop or tablet, and some also include power meters so you can train by wattage too.
Fully smart trainers can be controlled by the software. So, for example, the resistance will automatically alter to match the terrain you see on Zwift. You hit a hill on the screen and the resistance increases.
However, not all trainers described as 'smart' by the manufacturer can be controlled by Zwift.
The Kinetic Road Machine Smart, for example, doesn't automatically control resistance and neither does the Tacx Satori Smart, though to be fair they're now very hard to find in retailers. Caveat second-hand emptor though
For a fully smart, controllable trainer, the function to look for is ANT+ FE-C capability. FE-C stands for Fitness Equipment Control.
If you're in any doubt, head over to the Zwift website and find our which supported trainers are listed as 'smart' and which are listed as 'classic'.
They're noisier than you think
Electronically controlled smart trainers tend to be much quieter than air resistance turbo trainers of old, but there's always going to be a certain amount of noise associated with riding a bike indoors. Even the sound of the drivetrain, which you barely notice out on the road, seems much louder when you're inside, never mind the noise of the trainer, any fan that you're using or music that you're listening to.
The noise is unlikely to bother you on the bike, but it could be enough to disturb other people in the house or in the flat downstairs.
There's the issue of space
A smart trainer setup consists of your bike, the trainer, a computer or tablet, maybe a fan to keep you cool, probably a mat to protect the floor... That lot takes up a fair bit of room.
You might have enough space in your garage to leave everything in place between sessions but chances are that if you do your training in the house or flat you'll need to take it down in between times.
Zwift vs TrainerRoad: Which is best for you?
You might never ride outside again!
Some people really enjoy riding on a smart trainer, get immersed in the virtual world, love the time efficiency involved, the lack of traffic, the safety and the controlled conditions...
You might become a convert and never feel the need to ride outdoors.
You just might not take to it
On the other hand, you might be one of those people who just doesn't take to smart training. For many of us, getting out into the fresh air and seeing the countryside are among the main attractions of cycling and you don't get that on a trainer.
We'd advise you to try out a friend's setup, if possible, to find out whether smart training is for you before spending any cash.
Does your bike warranty cover it?
A warranty doesn't always cover your bike if you use it on a smart trainer, or any other kind of turbo trainer.
We published a story here on road.cc asking: is it okay to use your bike on a turbo trainer?
The short answer is that you might void the warranty if you do; it all depends on the brand.
For example, Canyon's Nick Allen told us, “Strictly speaking, using our bikes in a turbo trainer is not consistent with intended use. Unfortunately, any damage or breakage as a result would not be covered under our standard warranty terms and conditions.”
Other brands don't have an issue with it. The sensible option is to check in advance.
Road.cc, will you ever be reviewing their F/RD model? It looks lovely, but it's a bit of a trek from the UK just for a rest ride
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