Wattbike Atom

Wattbike’s new Atom is an update to a trainer that’s been in its range for a long time, and I last reviewed in 2020 (https://road.cc/content/review/next-generation-wattbike-atom-277405). This is really an incremental change: the physical bike is much the same, and there haven’t been any major changes to the electronics either. It’s put on £600 in that time, but then all its competitors are more expensive now too, and it’s still in the middle of the market rather than at the top. The updates to the ERG mode have definitely improved matters, and there are some other tweaks that have improved the bike’s usability a little bit, but overall it doesn’t feel like an awful lot has changed in five years, and it’s a more crowded market than it was back then.

The Wattbike Atom is still using the same chunky aluminium frame it’s used from the first edition; the only difference here is a cosmetic one, with the legs now the same black as the rest of the bike. It’s a weighty thing and arrives fully built, and it’s an idea to have a burly friend on hand to help you muscle it into place. The two skate wheels at the front mean it’s fairly simple to roll about on the flat, but getting it over thresholds and up steps is a two-person job. Once it’s in place it’s not going anywhere, and the adjustable feet mean it can deal with uneven floors pretty well.

Setting the Atom up is simple enough. You can adjust the saddle height and layback, and the stack height at the front and reach to the bars, simply enough with quick-release levers. Setting the handlebars and saddle setback used to require an allen key, but now it’s a lever like the rest, although it’s a little fiddle between the aero bars. Those aero bars double as an ipad mount so it’s likely you’ll want to keep them, but I removed the arm pads which take up a lot of hand space on the bars. You could replace the handlebars if you wanted: they’re just standard alloy bars, so if you like something specific it’s not difficult to swap them out. The same goes for the saddle, although the new Wattbike saddle is an improvement on the old one. One thing you can’t tweak is crank length: you’re stuck with 170mm, as opposed to other bikes where there are a range of options. It wasn’t an issue for me, but if you’re fussy about it then it’s worth taking into consideration.

Wattbike Atom: ride feel

Once you sling a leg over the Atom and start pedalling the ride feel is really good. It’s about the most solid of the smart bikes I’ve tried, with a heavy frame and a wide platform that means it’s rock-steady even when you’re trying to lay down your five-second power in Zwift’s new four-part Baseline thing. The Atom uses a chain rather than a belt drive, and that helps to give it a more bikey feel: belts are quiet and efficient but they don’t quite feel the same. I set the bike up to be a bit more upright that I would ride outdoors, like I normally do, and I found it plenty comfortable for the types of indoor ride I do, normally not more than an hour. If you like to go longer then you might prefer something with a of bit of movement engineered in, but personally I’ve never really felt like it was essential.

The Wattbike Atom uses an electromagnetic resistance system that’s controlled either by the lever hoods on the bars, or an app if you’re in ERG mode. I think it’s unchanged from the previous version of the bike, and it’s fine: you get resistance up to 2,500W, and given my five-second-power benchmarking the other day I can confidently say that at least 46% of that works just fine. I didn’t have any track sprinters on hand to check the other bit. The bike can also simulate a gradient of up to 25%, and you can use the shifters to change gear. The standard setup is 11 or 22 consecutive gears, but in the Wattbike Hub app (more on that later) you can also choose to emulate three different double-chainring setups for general riding, racing and climbing. You don’t get any kind of on-bike display to tell you what gear you’re in, which is something that the Tacx Bike Neo does well, and the KICKR Bike Pro significantly less well. It’s less of an issue now that gearing is displayed in-app in nearly all cases where you’d want it.

Gear shifts are okay. Some of the more expensive bikes use a motor brake system where the resistance unit can feed back to the rider through the pedals; that makes for much more realistic-feeling virtual shifting. Here you’re just increasing or decreasing the resistance, and while it’s nice and quick you don’t get the clunk of dropping a cog on a mechanical setup. The KICKR Bike Pro and Tacx Neo Bike Plus both do a really good job of emulating that, but they’re both a grand more than the Atom. Other bikes in the Atom’s price range, like the KICKR Bike Shift, use similar resistance technology, with similar results. The shift buttons aren’t the most positive-feeling – they’re a bit mushy – but aside from remembering which button does what (and that’s a me problem, not a Wattbike problem) they worked fine. I’m not sure the positioning is the best: they’re on the bit you’d grip hard in a sprint, so you can accidentally shift if you’re not careful.

Wattbike has made an effort to improve the ERG mode on the new Atom, which wasn’t the best I’ve tried, and it definitely has improved. There’s a small amount of smoothing on the signal, but not to the extent that it really affects your power numbers, and switching between power levels in and out of intervals is handled very well. Heading into a higher power interval from a rest is often problematic on ERG as trainers tend to over-egg the resistance, leading to a spike, before it dials back. That’s really not much of an issue with this trainer: there is a bit of a spike heading in to the hard work, but it’s better handled than most. There’s enough mass in the flywheel that it’s as easy as it ever is when you’re trying to smash out a session that’s at the limit of your capabilities. Overall the experience is very good.

Wattbike Atom: Power measurement

Wattbike claims a +/- 1% power accuracy for the Atom, which is as good as you’re going to see anywhere. It’s a bit difficult for me to say with certainty whether my review bike is within that range because I can only really benchmark it against a set of power pedals, which claim a similar accuracy. If they agree, and the numbers tally with what I know I’m capable of, it’s pretty likely that they’re both doing a good job. So, do they tally? Yes. Yes they do.

[Favero Assimoma Pro RS power trace – indoor]

Here’s an indoor session on Zwift, recorded on both the Wattbike and a set of Favero Assioma PRO-RS2 pedals. As you can see, the two power traces are very much in agreement, and there’s about a 1% difference between them, which you could reasonably put down drivetrain losses, as the bike is measuring power after the chain, and is reading slightly lower.

[Favero Assimoma Pro RS power trace – indoor mean]

The mean power graph for that ride shows very little difference, and most of it is at the top end, where a difference in sampling rates and times is as likely to be the cause of a discrepancy as any difference in actual power readings.

[Favero Assimoma Pro RS power trace – erg intervals]

An interval workout in ERG mode has a slightly higher discrepancy between the two, but this is likely to be more down to the fact that the Wattbike is doing some minor smoothing of the figures in ERG mode and so the peaks at the start of intervals, for example, aren’t as high as they are with the pedals, which don’t know it’s an ERG workout.

[Favero Assimoma Pro RS power trace – indoor cadence]

Cadence measurements are on point too: no drops, no big discrepancies, and the overall average cadence from the two systems is almost exactly the same.

Overall I don’t have any doubts that the Wattbike Atom is measuring power accurately. It entirely agrees with my power pedals, and both of those numbers are in line with what I know I’m capable of putting out. Even if the Wattbike was out by a couple of percent – and I really don’t think it is – then it’s measuring power repeatably and consistently, and so it’s a useful tool to discern long-term trends. It might not tally exactly with your outdoor power meter, if you use one, but my power profile on the road compared to in the shed is a bit different anyway.

Wattbike Atom: connectivity and app

​​The Wattbike Atom will feed this power data into your preferred training app via the normal channels: ANT+ FE-C, and Bluetooth FTMS. Both of those protocols also allow apps to communicate with the Atom to change the resistance for intervals, gear changes or gradient changes. I mostly used Bluetooth, as Zwift’s preferred connection protocol these days, and I didn’t have any issues with the connection during testing. It’s worth noting though that things are changing, connection wise. The KICKR Bike Shift, for example, also allows you to connect via WiFi, and even has a direct, wired option for the most stable connection possible. Other trainers allow power data to be transmitted to the app up to ten times a second, which makes for faster responses to sprint efforts in races. As the company’s premium smart trainer I’m surprised the Wattbike Atom hasn’t upped its game a bit here; it’s perfectly good for nearly everything you’re likely to do, but if you’re racing a lot indoors then a trainer with a 10hz race mode or a wired connection (or both) can give you an edge.

The Atom is compatible with most apps. Zwift is supported, as are Rouvy, MyWhoosh, FulGaz, Kinomap and TrainerRoad. Some of those (like Rouvy) require gear integration and display, others (like TrainerRoad) don’t, but it this bike should work with whatever you currently use. Wattbike also has its own app, the Wattbike Hub, which is free to use and has quite a lot in it. Wattbike markets the Atom at a much wider demographic than just cyclists, so there are training plans for other athletes using the bike as cross training, as well as a bunch of bike-specific workouts and plans. You can get your data out into Strava and Apple Health easily enough too.

The Hub app is also the place where you can see in the most detail what you’re doing on the bike. The main riding screen gives you a left/right balance, a pedalling efficiency meter for both legs, and also a radial graph which plots your power output around the pedal stroke. You can use this data to work on making your riding as efficient as possible. What works best for an individual rider varies, but the general advice that you’ll get from other platforms – working on all quadrants of your pedal stroke to maximise your efficiency – is also the goal here. If you’re a numbers-focused cyclist and you just want to smash through a load of intervals then the Wattbike app is enough on its own; if you want to ride with other people, race, or virtually visit famous climbs then you’re going to need another subscription for that. Which, if you’re considering dropping two and a half grand on a static bike, you probably already have.

Wattbike Atom: value and overall

So, is the Atom “The ultimate indoor smart bike trainer for dedicated cyclists” as Wattbike claims? I wouldn’t say so: there are other trainers out there which offer more functionality (the tilt mechanism of the KICKR Bike Pro, for example) and better resistance systems (the Tacx Bike Neo). In reality it’s somewhere in the middle of the ‘proper smart bike’ market and its most direct competitor is probably the Wahoo KICKR Bike Shift (https://road.cc/content/review/wahoo-kickr-bike-shift-306365). Wattbike has recently launched the Proton (https://road.cc/content/review/wattbike-proton-312341) which reviewed very well, and in all honesty feels like the better buy from Wattbike right now: okay it doesn’t have the top-end power (maxing out at 1,800W) but that’s a meaningless difference to 99% of riders, and actually the guts of the trainer are very similar, with the same claimed accuracy. It’s a full £700 cheaper for a bike that, for most people, is going to do the same job.

The Atom scores in its solidity: it feels like it will last forever, and there was no amount of sprinting – as a 100kg+ rider putting out 1,200W – that ever made it move an inch. The ERG mode is definitely better now, and the other minor changes (easier adjustability, better saddle) are also plus points. Personally though I think it’d be hard for me to make a case for the Atom over the excellent Proton if I wanted the flexibility to move between platforms, and if I was happy to be tied into Zwift I’d get the Zwift Ride with KICKR Core (https://road.cc/content/review/zwift-ride-kickr-core-310689). The Atom was good last time we tested it, and it’s still good, but I don’t think the minor changes for this iteration are enough to move it up the rankings.