DKN RB-4i Recumbent Exercise Bike Review

Over the years we’ve had the opportunity to test out quite a few models of CV machines manufactured by DKN. With a growing reputation for quality and an ever increasing use of hi-tech features in their machines, we were really keen test out their latest recumbent bike, the RB-4i. It’s predecessor, the RB-3i was a hit and the question on everyone’s lips has been whether the RB-4i offers any significant improvements or if DKN have simply provided us with a face-lifted version of the same thing. While that wouldn’t be such a bad thing, we were hoping for more, so did it deliver?

In truth the assembly really couldn’t be made much easier than it is. Like most bikes the main body is in one piece out of the box, so once the front and rear stabilisers were in position (very, very easy) – the rest went together smoothly. In all, the bike was ready to use in about 35min.

Visually, the RB-4i is strikingly modern and being black rather than white is quite a departure from its predecessor (which itself was pretty good looking). The sleek black and silver finish combined with the straight lines and some sexy curves makes for a really attractive bike that’d look great just about anywhere in the house. The feeling you get when looking at it is that this is a really high-quality bit of kit.

When you first get on the bike it’s impossible not to notice just how well-designed and comfortable the seat is. It’s absolutely brilliant. The base is very firm but really wide and the angle of the back of the seat can be adjusted just like a car seat by turning a knob while you’re seated. To adjust horizontally, again it’s just like a car. Reach under the seat and pull the bar up then slide back and forth until you get the best position. The distance settings are determined by a series of notches of which are spaced very close together so you can fine-tune your position. All the testers here were able to quickly and easily get the perfect distance to the pedals in just a few seconds. As you can adjust the seat in both ways while actually seated it’s extremely easy to get comfortable quickly with very little effort.

The open frame design looks great but is also very practical as it makes getting on nice and easy. The top of the powder coated frame sits just 6 cm off the floor making this bike really practical for those with mobility problems or for elderly users. In addition to the low step through there are two fixed handles either side of the console. They’re a nice thickness and have a rubberised coating which provides a really great grip for those needing assistance getting on and off the bike.

The console sits on a hinge that allows you to tilt it towards or away from you so that regardless of how short or tall you are the display is always in line with your natural visual angle meaning you always get a great view of the screen. If you want to use a wireless chest strap for monitoring your heart rate the console comes with a built-in Bluetooth Smart heart rate receiver that’ll work with any Bluetoot chest strap and you also have the option of the pulse sensors on the handles either side of the seat. The console itself is a big departure from what we’ve seen on DKN bikes before in terms of looks and feel. The robust large black casing even has an accessories tray which is ideal for setting down a phone, some keys and various other smaller items and also includes a lip for holding a tablet or smartphone (more on that later). The layout of the controls for selecting programmes, adjusting resistance, activating the Bluetooth functions and resetting the computer is well thought out and makes instant sense, even at first glance. The buttons themselves are large and easy to read making for easy control even during your workout.

The display itself is a two colour 5” (12.7 cm) affair with good contrast that makes for quite a wide vertical viewing angle. All the characters on the screen are large and easy to see, displaying time (elapsed or remaining), pulse, speed/rpm, watt, distance (elapsed or remaining) with a clear bright readout showing which point you’ve reached in the programme you’re on.

Speaking of programmes the RB-4i has plenty of them including, manual, beginner, advanced, performance (interval) and watt. The interval training programmes work well due to the fast change of resistance on this bike. It takes just over 8 seconds to go from min to max and just over 10 to come back down again. While on paper this doesn’t sound much, in practice during a workout we found it to be just right, providing a really nice interval training experience. Using the watt or cardio programmes you can set a target for each respectively, though use of the cardio programme does require a wireless chest belt. There are 4 pre-set programmes in each category of beginner, advanced and performance. Each of the programmes provides you with the option of increasing the resistance level from the base level. One touch up a notch and every section of the workout increases by the same amount. This means that the bike can provide a seriously testing workout on any given programme no matter how fit or strong you become, giving it great longevity. You’re simply very unlikely to outgrow it.

Like most of the other CV machines in the DKN range the RB-4i is compatible with the ‘DKN Motion’ and ‘DKN i-world’ applications. If you have an iPad, or other compatible Android tablet device, you’ll be able to connect it to the bike via BlueTooth and use the app to control your workouts. The DKN i-world app allows you to map out your cycling routes on Google Maps. It’s nice and easy too, just press and hold on your start point on the map, then press and hold your end point. Then when you’ve got your route marked out, just press start to get going. If you’re going uphill on the map the app will automatically increase the resistance and vice versa. You then have a choice of map, satellite or street view to monitor your progress through the course. Street view, as expected, is a series of stills and not a smooth video of your chosen course (oh glory be the day that this is a smooth, lifelike video but we’ll have to wait for Google on that front). We found this app quite a lot of fun to use but it must be said that it’s definitely not an accurate simulation. So if you’re expecting it to exactly mirror your local hill and provide real-world precise distances and gradients then this isn’t the app for you.That being said, the app is slick, smooth and close enough to the real thing to make things interesting and certainly provides some entertainment while you’re working out. It’s good fun and in our opinion a nice feature worth having. We have heard reports of the app not working smoothly but it worked perfectly on our ipad mini so we’d suggest double checking your device is compatible before purchasing the bike if this is a make or break feature for you.

As standard, the RB-4i console offers a choice of 4 user profiles. Each of these allows the age, weight, height and gender of a user to be stored and this data is used to increase the accuracy of feedback provided, such as calorie consumption. With the DKN Motion app, the concept is extended further to allow 12 different users to be configured on the app with additional information of the users name and an avatar. All of the functionality in the console is on offer through the Motion app so it essentially changes the user interface from console to tablet based. Having a tablet as the user interface really comes into its own when programming a custom programme. It’s just far quicker and easier to do it via the app than the console, though the console does do a perfectly good job.

The DKN Motion app also adds a recovery test function to the RB-4i. This works by measuring the rate at which your heart rate returns to resting state after a workout. The quicker it returns to resting rate, the better your score, the fitter you are.

The RB-4i has a hefty 11kg flywheel. This, combined with the quality of the internal components, gives a really comfortable and smooth experience. As you’d expect from a DKN machine the ride is also whisper quiet so the bike lends itself to use early mornings or late evenings without disturbing anyone in the household. The addition of a water bottle holder front and centre on the main stem is also a welcome addition.

The user-friendly design of this recumbent makes it a great choice for a wide range of users. So if you’re just starting out to get fit, or are already a seasoned fitness freak like us the RB-4i really does have a lot to offer.

DKN have produced a video showing off the RB-4i and we’ve included it below:

Best Price

Currently available for £649.00 from DKN

To get the DKN RB-4i Exercise Bike for only £649, enter voucher code Rb4i on DKN basket page!

Review Summary - In Brief

With the RB-4i, DKN have produced an absolutely fantastic exercise bike with a heavy 11kg flywheel for a smooth feel, a great resistance range, user profiles, heart rate control, tablet connectivity and a brilliant, comfortable seating position. This is a great recumbent at a price lower than we'd expect for the quality on offer!

DKN RB-4i Specifications

    • 11kg (24lbs) flywheel
    • 32 levels of resistance
    • 12 programmes
    • 4 user profiles
    • Large multifunctional colour LCD display
    • Heart rate measured via hand pulse sensor or Bluetooth Smart wireless receiver (chest strap optional)
    • Feedback: Speed, time, RPM, distance, calorie burn, heart rate, WATT
    • Compatible with Kinomap, Vescape
    • Max. User Weight: 150kg (330lbs)
    • Dimensions (L x W x H): 150cm (59”) x 66cm (26”) x 112cm (44”)
    • Product Weight: 50kg (110lbs)
    • Conveniences: Large and padded adjustable seat with back support and hand rests
    • Warranty: 2 years

DKN RB-4i Recumbent Exercise Bike - Console / Display Unit

DKN RB-4i Recumbent Exercise Bike - User Reviews

The Pros

  • Excellent seat and seat adjustment mechanism
  • Bright, clear screen
  • Solid as a rock
  • Multiple difficulty levels for longevity
  • Multiple apps for tablet connectivity
  • Looks great, feels great

The Cons

  • It's not small
DKN RB-4i Recumbent Exercise Bike Reviewer Ratings


Appearance - 9
Smoothness - 9.5
Comfort - 9
Programmes - 8.5
Ease Of Use - 8.5
Warranty - 8.5
Value for Money - 8.5
Best Price

Currently available for £649.00 from DKN

To get the DKN RB-4i Exercise Bike for only £649, enter voucher code Rb4i on DKN basket page!

Also see our Exercise Bike Comparison Table

Whilst every effort is made to give you accurate information we cannot guarantee the technical specification. Models change on a regular basis and may differ slightly from the above review. We recommend you contact the retailer if you have a question regarding technical data. Please read our Legal Disclaimer

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