adidas C-21 Exercise Bike Review

Adidas is one of the world’s most famous sports brands. With a reputation for premium-quality products that are used by the world’s best athletes, the famous 3 stripes are generally a stamp of quality on any product. We got our hands on the adidas C-21 upright exercise bike and put it through its paces to find out what it’s like.

The assembly process is straightforward here and only took about 45 minutes which is fairly standard for this type of bike. The assembly guide consists of a set of nice clear and easy to follow diagrams and all the components on our test model fitted together without any problems in seven stages. This is a manageable job for pretty much anyone, regardless of their level of DIY/Flat Pack furniture skills and can be completed without the help of a second person, though having someone help by to holding a few bits does help on a couple of stages.

In terms of colours, adidas has gone for a classic look with predominantly grey/silver but then has spiced things up with a large red LED circle which lights up when the bike is in use. This red LED circle gives this bike a decidedly futuristic feel and while it’s a little bit different and a bit of fun, we really like it.

Anyway, after dwelling on the cosmetics we turned out attention to the important things on this bike and we’ve got to praise the overall design and build. This mid-priced bike delivers a high-quality ride! Hidden away inside the casing is a nice hefty 9kg (20lbs) flywheel; the weight of which, along with other quality components contributes to the smoothness and stability that can be felt with each turn of the pedals. No matter the resistance level chosen (the high end of which really is pretty challenging) the action is smooth and uniform throughout the cycle which results in a quality feel. Another element that adds to the quality feel of this bike is the saddle which is large and soft without being too big to make for a good cycle seat. Something quite unusual at this type of price point is that the C-21 is a self-generating bike, so each revolution of the pedals actually charges up rechargeable batteries in the machine (batteries not included). This feature means that the C-21 doesn’t need to be plugged into the mains and saves having to have a power cable running from the bike to a power socket making it easy to locate the bike in a preferred location, rather than its position being determined by the location of an electrical socket.

The C-21 has a stated maximum user weight of 150kg (331lbs) and in testing proved that it happily accommodates tall riders too. At 6’3” it’s common for one of our team to find bikes that don’t feel too great but here the seat has plenty of adjustment both vertically and horizontally to enable a good riding position to be found. From the shortest tester to the tallest, all found it easy to get a good riding position so this bike is definitely a good choice if there are multiple regular users in the household. One of the striking things about this bike is just how well it’s put together. A button press feels good, the seat adjustment mechanism is positive and sturdy. All the metal components that you handle during assembly all feel nicely heavy in the hand with thick-gauge steel, including the handlebars and seat post right down to the front and rear stabilisers. All around this is an impressively built piece of kit.

The console features 15 programs (manual, 12 pre-set workouts, target heart rate mode, Watt mode) including all the usual favourites for weight loss and cardio work as well as a recovery test. The workouts themselves are effective and do exactly what they say making it easy to select a workout that will actually deliver in the areas you’re targeting. The console display itself also works really well with large, clear characters nicely divided into clear sections for time, speed, distance, calories, pulse and programme indicator making it very simple and easy to use, which is always a big plus. There are 24 levels of resistance, and the top end of that scale should be enough to challenge anyone that’s likely to be using this bike. Indeed, the C-21 has all the tools needed to satisfy the needs of a novice user through to a more seasoned exercise enthusiast.

Other features include a Bluetooth wireless heart rate receiver, tablet holder, stereo speakers with Bluetooth connectivity, 4 user profiles, water bottle holder and leg levellers. It also comes with a 2-year warranty from adidas for peace of mind, not that, based on our testing, it’s likely that you’ll need it!

Best Price

Currently available for £499.00 from

To get the adidas C-21 Exercise Bike for only £499.00, enter voucher code C21-40 on the basket page!

Review Summary - In Brief

The adidas C-21 may not have some of the latest tech, like a colour touch-screen, but it makes up for this with sheer build quality and performance. This is a well built and well thought through upright exercise bike. It has been designed to deliver the performance and comfort that makes consistent, long-term training enjoyable and effective. And it definitely hits the mark. The focus here is on performance and it delivers with aplomb. With well designed preset workouts that are challenging and effective, a good range of training options and features, and rock-solid build quality, this a good deal of bike for the money. As such this is a model that we're suitably impressed with to make it our bike of the month in this category.

adidas C-21 Specifications

    • 9kg (20lbs) flywheel
    • 24 levels of computer-controlled magnetic resistance with direct resistance keys on the console
    • LCD display
    • Feedback: Time, speed, distance, calories, Watts, RPM, resistance, pulse
    • Programmes: 15 (manual, 12 pre-set programmes, target HR mode, Watt mode)
    • User Profiles: 4 (each with age / gender / weight / height)
    • Hear rate measurement via hand pulse sensors and Bluetooth Smart wireless receiver (chest strap included)
    • Seat: Wide, densely padded seat with horizontal and vertical adjustment (seat height: 67cm – 92cm (26″ – 36″))
    • Pedals: High-grip pedals with adjustable straps
    • Transportation wheels
    • Extras: Water bottle holder, leg levellers, Ultra series red LED lighting, tablet/smartphone holder
    • Audio: stereo speakers with Bluetooth connectivity
    • Dimensions in use (L x W x H): 107cm (42”) x 57cm (22”) x 147cm (58”)
    • Max. User Weight: 150kg (331lbs)
    • Product Weight: 44kg (97lbs)
    • Power: Console is powered with seven AA batteries (not included)
    • Warranty: 2 years

adidas C-21 Exercise Bike - Console / Display Unit

adidas C-21 Exercise Bike - User Reviews

The Pros

  • Comfortable gel padded seat
  • Suitable for a wide range of users
  • Rock solid build quality
  • Good range of workouts
  • Self generating

The Cons

  • If we're being picky, no interactive features
adidas C-21 Exercise Bike Reviewer Ratings


Appearance - 9
Smoothness - 9
Comfort - 9.5
Programmes - 8.5
Ease Of Use - 9
Warranty - 8.5
Value for Money - 10
Best Price

Currently available for £499.00 from

To get the adidas C-21 Exercise Bike for only £499.00, enter voucher code C21-40 on the 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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