BKool 1.0 Turbo Trainer

On the face of it, the BKOOL sounds like the bargain of the century – a power enabled turbo with variable resistance linked to first person videos, all for just shy of £430. In a market where those sort of features will typically set you back the better part of a grand, it looks very promising indeed. Surely it's too good to be true?

The answer to that is: sort of. Those looking for absolute accuracy and precision from the power calculation will be disappointed by the BKOOL as its lack of calibration protocol means that the power numbers are an estimate at best. For those more interested in the real-life videos, the BKOOL features a massive library of such videos available on a cheap subscription model, which, combined with the realistic road feel make it a great tool for simply getting in the miles over winter.

The unit

The actual BKOOL turbo trainer itself looks relatively standard from afar, but closer inspection reveals a key difference to how the bike is attached. Instead of clamping the roller against the tyre like almost every other turbo out there, the BKOOL relies on the weight of the rider to provide the contact force between tyre and roller - the consequences of this design are numerous:

Firstly, when not attached to a bike, the BKOOL naturally wants to lay flat as the hinges on the support arms are free to rotate. This makes it quite a bit easier to stow away, as you don't have to adjust any bolts or clamps to get it to fold flat. In addition, different sized wheels are automatically catered for without having to make adjustments. The resistance unit at the rear is also hinged and can be folded in, further reducing the BKOOL's footprint when stored.

Secondly, the contact force will vary depending on whether you are sitting in the saddle or standing on the pedals. This in turn will affect the resistance that the unit delivers which in turn affects the calculated power. As such, the unit isn't really very suitable if you're going to be doing any sort of extended out of the saddle riding – not usually something you'd do on the turbo anyway, but this quirk is worth bearing in mind when assessing the accuracy of the power readout.

Finally, tyre pressure will also have a significant impact on the calculated power, as this will affect the rolling resistance as well. For consistent results, making sure that the pressure in your rear tyre is the same every time you hop on the turbo is a must.

As a kind of side note, I found that there seemed to be quite a lot of tyre debris deposited on the resistance unit after only a few rides. However, further use hasn't revealed tyre wear to be any greater problem that on a standard turbo - the shaping of the resistance unit behind the roller, and the white colour just seems to collect the used rubber and make it stand out.

The frame itself is manufactured from steel and is appropriately hefty for a turbo trainer. Despite being able to lay it flat, its sheer mass means that it's not really the ideal turbo for travelling with. The fact that it requires a mains input also restricts its use for anything outside a building, such as a race warm up.

Having mentioned its weight, the one disappointing aspect of the turbo unit itself is that it's not the most stable when really laying down the power. Given that its usage is effectively limited to a dedicated turbo trainer area a.k.a pain cave, I would've liked to see a design with a larger footprint to help in this regard.

Also included in the package is a single position front wheel block, which positions the bike level, and the ANT+ sensors you'll need to get the most out of the trainer: heart rate and cadence.

The web interface

The key to unlocking the potential of the BKOOL is the web interface, where you are able to create personalised workouts, download first person ride footage, and even keep track of your progress via a training diary. Furthermore, the website also acts as a social media-type forum where users can post routes, create their own clubs, and even compete against each other. Sort of like Strava for the sun-deprived.

In terms of appearance and functionality, the web interface is on the basic side, but easy enough to understand and get the hang of it. It's clear that 'flashiness' has been compromised to meet a certain price point, but this isn't necessarily a bad thing.

What could be improved though, is the time it takes to go through the whole process of creating a workout in the first place - even a basic fixed time and constant resistance workout requires numerous clicks and at least five minutes to set up.

Further frustrating matters is that fact that the web interface is the only way that the user is able to create a workout in the first place. That's a problem if you don't have an internet connection for example. The issue can be gotten around to some extent by 'favouriting' workouts (only available to Gold subscribers), which saves them on the desktop application for much easier access, but using the BKOOL will always require some sort of planning ahead – this isn't a unit you can just hop on and knock out 30 minutes of riding.

Ride Options

One of the BKOOL's strengths is the wide variety of workout types that can be created using the online system. Most basic of all, you have 'fixed time' or 'fixed distance' workouts which are based on an elevation profile which you chose from the significant online library. It is possible to modify these profiles in certain ways – such as changing wind strength, road surface or even gradient – and also add virtual riders who you can compete against to complete the route first. As the gradient of the profile changes, so does the resistance of the turbo unit, leading to a more lifelike feel.

If there aren't any profiles that tickle your fancy, it's possible to upload your own (GPX, CSV, PGMF, CAF and HRM2 formats accepted) from a previous ride or even one created from the numerous ride planning websites out there. The BKOOL software supports integration with Google Earth, so it's also possible to see your avatar track your progress along the route as you pedal. The quality of this footage is highly dependent on the coverage that Google Earth provides for that given geographical area.

There's also a velodrome mode, where you can specify a number of laps to complete or a specific ride time, and then watch as a little dot, that's you, moves around a 2D velodrome. It might not sound too interesting, but with the included lap splits, I found myself to be strangely drawn in by it. During this activity, the trainer unit is delivering a constant (quite low) resistance, so you'll have to use your gears to modulate your effort.

For many, the main attraction of the BKOOL is the option of riding along to the first person videos, with variable resistance matching what is on screen. The process of creating these workouts is the same as for a simple ride: select a certain time or distance you want to ride for, and the online system will come up with a number of videos which more or less fit your needs. You can also differentiate between flat, hilly and mountainous profiles.

The library of videos is very large, and the subscription based model (see below) means that you have an unlimited choice in what to watch. Most of the videos are from roads in Spain (where BKOOL is based), but classic climbs of the Tour such as the Galibier and Madalene, as well as some pretty horrific (in a good way) Italian climbs are included. If going for a 'fixed distance' type workout, the video playback speed is based on the effort you are putting out, so in some cases, these climbs can make for some very long turbo sessions indeed – perfect for getting in the miles during winter.

Included in the catalogue are a few videos taken in-race from the Vuelta a Espana, which put you right in the action. One in particular that I found interesting is taken from a team car following a rider around the time trial course. Being able to see the speed of the rider first-hand, and the line choices he makes going downhill was fascinating.

Finally, there is also the option of creating so-called 'multiplayer' workouts. These are essentially open sessions based of the workout types described above, that anyone can join and compete against each other in. If you need added motivation on a dreary winter evening, this may well just provide it.

Packages

Access to all the various features of the BKOOL is dependent on the level of package (Bronze or Gold) you pay for, which follow a subscription payment model.

The Bronze option is the default, free option when purchasing the BKOOL, and gets you access of all of the ride options except for the real-life videos and multiplayer, in addition to the training log aspect of the website.

The Gold subscription, available for 10 euros per month (or less on a yearly or half-yearly basis), adds in access to the full catalogue of real-life videos and the multiplayer mode, in addition to being able to 'favourite' workouts (useful if you want to use the BKOOL offline).

Compared to other first person style ride videos which can often run close to £100 for just a single video, the Gold subscription is significantly cheaper, and gives you access to a much wider range of footage. Also, the fact that you can subscribe on a monthly basis means that you can choose to spend the money in winter, when the turbo is likely to get most use, and then revert back to the bronze subscription in the summer when you can ride outside more often.

Desktop application

Much like the web interface, the desktop application – called BSIM and currently only available for Windows - is a little basic visually, but it does the job well. Workouts created using the web interface for this particular day (or those workouts saved as favourites) are downloaded to the application when it starts up, ready to be performed.

The BSIM software communicates with the physical unit using the provided USB stick, which uses the wireless ANT+ protocol. While the BKOOL includes a heart rate strap and cadence sensor as part of the package, use of this open protocol means you can use any of your own sensors (HR, speed, cadence but not power) that are ANT+, meaning you aren't tied into their proprietary sensors.

The software is also used to update the firmware on the trainer unit via USB cable. Firmware updates are very infrequent – I've only had to do one in nearly a year's worth of testing – so this isn't something which gets in the way too often.

In use

Once you've gone through the whole process of creating a workout online and firing up the desktop application, it's time to get down to the business of actually riding. Since the default setting during the workout creation is for warm-up: 'on', most rides will begin with a 10 minute period of very low resistance to get the legs spinning. At any point during this you can skip straight to the meat of the ride by stopping (rear wheel stationary) for three seconds. This is handy as I suspect most people will find this warm-up period too long, especially given that there are no onscreen prompts to help pass the time.

Once into the workout proper, a banner along the bottom of the screen will display your current and average speed, heart rate, cadence (assuming you've got all the relevant Ant+ sensors enabled) and energy expired, as well as an estimation of current and average power.

The integration of power data is notable, given that most other power enabled turbo trainers run at twice the price or more of the BKOOL. As noted previously, the power is estimated from wheel speed and the current level of resistance (derived from road gradient) based on a known power curve. However, the unit doesn't support any sort of calibration which is surprising given that variables such as tyre pressure will surely have a large impact on the estimated power.

Compared to the Power2Max power meter that I usually ride with (quoted accuracy of +-2%), the estimated average power from the BKOOL was usually within about 10% of so of the average power measured using the power meter. The differences between instantaneous power were less consistent however, and varied over the power range and with cadence also. And of course, the BKOOL estimate gets thrown way off if you happen to get out of the saddle at any point.

As such, the power aspect of the BKOOL trainer is more like an added-interest feature than something on which to base all your training around. At this price point, this level of accuracy seems quite fair.

At the top right of the screen you get a display of time taken and distance ridden, while the top left displays the performance of the virtual competitors you included when creating a 'single player' workout, or the performance of other users if you are in 'multiplayer' mode.

Overall, the display is well laid out and doesn't interfere with any of the action on screen when doing a first person video workout, for example. It lacks any sort of customisation, which will frustrate more data focussed users, but all the main metrics are there.

The ride feel of the turbo is good and does a remarkable job of replicating the sensation of actual riding. The transitions in resistance as the gradient changes are smooth and gradual which help deliver a more natural feel to the experience as you end of shifting gears in much the same way as you would on a proper road.

Adding to the real-life feel are the first person videos. The quality on these is decent but not HD outstanding – good enough to be able to easily identify each particular climb and provide some sort of mental distraction.

Playback smoothness is, in general, pretty good but it does come with a few quirks that can take you by surprise. When operating under the 'fixed distance' mode (where the playback speed is related to the effort you are putting in), it is possible to overrun the videos on the downhills (and the uphills too if you are some kind of monster) so that the resistance being delivered by the turbo unit doesn't correspond with what's being shown on screen.

This only happens if you really push things (300+ W) when going downhill and the on screen speed display turns red to notify you that you are exceeding the allowable speed. If you don't back off, it can lead to the slightly surreal experience of suddenly experiencing significant resistance associated with a steep hill, while the video is still showing you on a descent. Note that this problem doesn't occur when doing a 'fixed time' workout, as the video playback speed is effectively fixed in this case.

While the first person videos are great if your aim is just to get in some indoor miles, the fact that they are so lifelike means that they aren't great if you have a specific interval set to be doing. In this case, I found the best option was to create my own profile online, using a constant gradient of around 4%, and then using the gears on the bike to vary the resistance from there. The velodrome option can be used as a more controlled setting, but I found the resistance level to be a bit too low for some high power, low cadence drills.

Overall, the in-use experience is very good, and the wide range of possible workouts mean that it's easy to find distractions to help pass the time. There are other (more expensive) trainers out there that do a better job when it comes to power accuracy and integration of specific training tools, but for a unit to help get in the miles when the weather is atrocious, the BKOOL is ideal.

Verdict

Though it does have a few quirks, the BKOOL is an excellent value turbo trainer that includes many features not usually seen at this price point, making it ideal for anyone who spends a lot of time riding indoors.