Best Bike Trainer of 2021
|Price||$284.24 at Amazon|
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|$499.99 at Backcountry|
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$239.99 at Amazon
$75.74 at Amazon
$49.88 at Amazon
|Pros||Quick setup, easy operation, durable, stable, communicates with training apps, low noise||Durable, cheaper than direct drive models||Lightweight, affordable, durable design||Quick setup, easy to move around, light, simple design||Very affordable, light, easy to carry, store, and move around|
|Cons||Limited max resistance, roller can heat up and accelerate tire wear, no power data, no control||Heavy, needs electric power for use, lacks versatility with boost hub spacing, expensive for a tire drive trainer||Loud, mag resistance has limitations, assembly takes some effort, requires speed sensor purchased separately to connect to third-party apps||Louder, unrealistic road feel, low max power, no controllable features, not supported by many popular training apps||Limited resistance, cable shifter, durability and quality issues|
|Bottom Line||This trainer sits at the crossroads of great value and high functionality||When it comes to tire drive trainers, this is a top model with impressive road feel for its design||This is a utilitarian mag trainer that provides more reliability than others in the low-end price range||This is the trainer you get when you’re just trying to get your legs spinning without paying a ton||This trainer should be considered a last ditch option—workable, but not the best|
|Rating Categories||Saris Fluid 2||Wahoo Fitness Kickr...||Saris Mag+||BalanceFrom Bike Tr...||FDW Bike Trainer|
|Connectivity And Power Accuracy (25%)|
|Road Feel (25%)|
|Specs||Saris Fluid 2||Wahoo Fitness Kickr...||Saris Mag+||BalanceFrom Bike Tr...||FDW Bike Trainer|
|Type||Tire drive||Tire drive||Tire drive||Tire drive||Tire drive|
|Weight (lbs)||21 lbs||38 lbs||20 lbs||19 lbs||19 lbs|
|Compatible Platforms-TrainerRoad, Zwift||Yes, both. Also Rouvy and The Sufferfest.||Yes, both. Also Wahoo Smartphone App, Rouvy, and The Sufferfest.||Zwift, TrainerRoad||None.||None.|
|Communication Protocol||ANT+ BlueGiga USB||ANT+ FEC, Bluetooth Smart||ANT+ FE-C or Bluetooth FTMS||None||None|
|Dimensions L-H-W (inches)||28" x 21.5" x 15.7"||26" x 18.25" x 28.75"||28" x 21.5" x 15.7"||23.9 x 20.1 x 7.6||23.9 x 20.1 x 7.6|
|Storage Dimensions LxHxW (inches)||20.5" x 9" x 20.75"||20.75" x 7.5" x 20.5"||20.5" x 9" x 20.75"||23.9 x 20.1 x 7.6||23.9 x 20.1 x 7.6|
|Power Comparison||10 watts, 5%||10-15 watts, 5%||N/A||N/A||N/A|
|Decibel @ 230 Watts||64.7 dB||54.5 dB||66.5 dB||65.2 dB||65.2 dB|
|Roll Out Time @ 200 watts||15 seconds||45 seconds||4 seconds||5 seconds||5 seconds|
|Flywheel||3 lbs||10.5 lbs||Magnetic||5 lbs||5 lbs|
|Axel compatibility||120mm, 130mm, 135mm compatible || Thru-axle available for 142mm and 148mm through CycleOps.||130mm, 135mm compatible || 142mm adaptor available through Wahoo.||142x12mm and 148x12mm bikes||130mm and 135mm || May need 3rd party adaptors for 142mm and 148mm||130mm and 135mm || May need 3rd party adaptors for 142mm and 148mm|
Best Overall Smart Trainer
Tacx Neo 2T Smart
The Tacx Neo 2T Smart earns our highest honors. If you want the top-of-the-line trainer, look no further. The Neo 2T is probably the smoothest ride out there, yet when you're Zwifting around on terrain like cobbles and boards, it'll bump and rumble to simulate it. It's the only trainer to simulate freewheeling on descents. It never requires calibration and is the most accurate power reader on the market. Did we mention it requires zero calibration? If you don't have a power outlet near you, no problem — it will run on your power as you ride, so you can still sync up to your phone and control resistance. And it's one of the more versatile trainers, fitting most frames, axles, the three major cassette brands, Shimano, SRAM, and Campagnolo (make sure to look into adapters and hubs beforehand).
You might be thinking, why consider any other trainer? We found a few areas to consider before jumping all-in on the Tacx Neo 2T. This bike trainer was one of the heaviest we tested. It needs the weight to get the performance it delivers, but it does make it a bit of a pain to move around the house or take out on the road. If you have a place to put it and keep it, you probably won’t be bothered. It's a premium bike trainer and it comes at a premium price. This trainer is for serious riders who want to get the most out of their training sessions, either as part of their in-season training or in the off-season when it's freezing outside. If you are looking to take your training to the next level, this trainer should be seriously considered.
Read review: Tacx Neo 2T Smart
Best Bang for Your Buck
Saris H3 Direct Drive
The Saris H3 Direct Drive packs in a lot of performance for its price point. It's probably closer to top-shelf bike trainer specs and performance, but it's hundreds less than the premium trainers. Saris reduced the price of the H-series with the release of the H3, bringing you a more affordable high-quality trainer. It features a new motor design that improves its handling of power changes and requirements, so your sprinting, climbing, and ERG training are even smoother. The accuracy remains at a solid +/- 2%, but improvements have reduced drop-outs and spikes, so the overall accuracy is actually better in the H3 than in previous iterations. And it's the quietest trainer in our lineup, with a claimed noise level of 59 dB, though we measured it even lower, at 55 dB. Truly, it's one of the nicest trainers on the market and at a prettier price than the competition.
It's not all sunshine and rainbows, though. You don't get the H3's level of performance without a lot of dense machinery inside. It's a heavy thing, coming in at nearly 50 pounds. Even the hulkiest cyclist will find it to be a pain when moving the trainer around. It's also worth pointing out that it requires periodic calibration to remain accurate. That's pretty common for bike trainers, but a few competitors out there have machines that don't require it even once. The folks who will get the best use of the Saris H3 are riders who are serious about training indoors and want to shop on a budget without much sacrifice in performance or convenience.
Read review: Saris H3 Direct Drive
Best Mid-Range Value
Kinetic Road Machine Control
The Kurt Kinetic Road Machine | Control is an excellent mid-level trainer. It hits the right mix of versatility and affordability. It's an easy trainer to get set up and rolling pretty quickly. It's a smart control trainer, so not only do you get your performance data, like speed and power, but you get to control it. It's one of the few tire drive trainers with control - hence the name. So you're now fully integrated into the interactive training world of Zwift and TrainerRoad and the other sweet programs out there. It's also offered at a super competitive price point. Not a lot of trainers get you into the interactive control world without making you cringe at the expense.
There are a few drawbacks to this trainer. It's a tire drive trainer, so there are inherent limitations on performance. Power accuracy tends to be a little lower for this style of trainer. It's no different with the Kinetic Road Machine | Control. It's accurate to about +/- 5%. That's doable for a mid-range trainer but not as accurate as the premium direct drive trainers. Then again, it's a fraction of the price and gets the job done. One limitation is this trainer needs to be plugged in to have the control features work. That's not ideal, but there are very few trainers that can overcome that problem. Riders looking to get into the virtual control world who don't want to splurge on a trainer that costs as much as their bikes themselves will get a lot out of the Kinetic.
Read review: Control
Best Tire Drive
Saris Fluid 2
Looking for a simple bike trainer to get you up on your bike in the winter without the hassle and full paycheck? The Saris Fluid2 will do exactly that. It's a straightforward trainer that's super easy to set up and get rolling. We tested it with the speed or cadence sensor (a very worthwhile option) that easily pairs with Zwift, Rouvy, and all the other major training apps, so you're not flying blind. And it's not just any old tire drive trainer. It actually feels like you're out on the road. The former company CycleOps, now owned and rebranded by Saris, has earned its excellent reputation for unmatched road feel in its fluid resistance trainers, and that's on show with the Fluid2. It follows a basic progressive resistance curve, but it has the perfect amount of responsiveness, inertia, and rollout/spin-down to mimic the road. It's also one of the lightest bike trainers on the market, making it super easy to move around, store, and take out on road trips or to warm up before races.
Of course, the limitations of this model are found across all tire drive trainers. While it's great in comparison to the models in its class, it still can't match the road feel, smart data, and power measurement accuracy of direct drive trainers. And like most tire drive models, it doesn't have control, so your Zwifting won't be quite as interactive as it could be. But hey, it also doesn't have the price tag. If you're after a practical, easy, natural-feeling tire-drive trainer, it doesn't get much better than the Saris Fluid2.
Read review: Saris Fluid 2
Why You Should Trust Us
Our testers Curtis Smith and Ryan Baham got their roles testing this gear because they're cycling freaks. They live and breathe the sport and all its accouterments. They spend most of their year in the saddle, planning how to be in the saddle when the weather's bad, how to be in the saddle in new places, and how to be better in the saddle when they're spending time out of the saddle. They spend a ton of time riding and researching on their own, and they've been doing it for years.
We obsessively test these bike trainers, putting in a huge amount of hours, losing gallons of sweat, and occasionally, even a little blood. We ride these trainers with an eye for smart connectivity with smartphones, computers, and fitness applications. We double-check all of the power readings with an outside power meter. We also pay attention to the portability of each unit, ease of setup, and how the feeling of each trainer compares to the feel of the road. Rest assured, we have all the bases covered.
Related: How We Tested Bike Trainers
Analysis and Test Results
Our goal here is to bring riders the best bike trainer review possible. As no-bull riders ourselves, we put out the review we want to read. We do all the research and buy the trainers at market rates from the same places you do, then ride them hard and see whether they're worth recommending to our friends (including you).
The great difficulty here is maintaining impartiality and objectivity, especially when looking at trainers that can range from less than a hundred bucks all the way into the thousands. We address that through measures and perspectives. We've devised five reasonably objective performance measures, which are assigned weighted scores, to suss out the comparative performance of each trainer. But we also keep users and their requirements in mind, so in our evaluations, we're clear about the purpose and best use of each trainer. So while a trainer might have a lower score, we might still highlight the trainer as ideal for a particular type of rider, like someone who won't be chasing marginal gains and wouldn't benefit from premium frills.
Related: Buying Advice for Bike Trainers
The price of the trainer tends to move in line with performance. The higher the price, the more capabilities and better the dependability while the lowest priced items are usually stripped-down with lower dependability and quicker wear. Smart control features also are either limited or sometimes not present on the low-priced end of the market. However, most smart models come with ANT + and Bluetooth connectivity now, so you can still use third-party apps like Zwift, The Sufferfest, and TrainerRoad for an engaging session of pains and gains.
After hours of testing, the Kinetic Road Machine | Control proved to cover most cyclists' needs in a bike trainer at a very competitive price. It has just enough smart features to keep us tuned into our workout at one of the lowest prices in this review. It's also simple to use and light enough to cart around wherever you'd like. However, if you want a taste of the top echelon of bike trainers these days, go for the Saris H3. It's a clear jump up in features and road feel from the tire drive models and isn't far behind the direct drive models in terms of performance, but it costs hundreds less.
Connectivity and Power Accuracy
Not all bike trainers give you the same features. A lot of the lower-end trainers don't even have connected features like speed, cadence, or power, so testing was sometimes nearly impossible or done as compared to outside sensors. In the case of power, how does the resistance curve work with our gearing and cadence? Are we putting out 100 watts to go 25mph when we should be hitting 220? All of the lower-end trainers limped along in this measure, but we address the relevant concerns in the in-depth analyses for each trainer.
When it comes to smart trainers, one of the most important considerations is connectivity with companies' in-house applications and, probably more importantly, the broad array of third-party training apps like Zwift. Because a drop here could tank an entire training session or even block a rider from an entire virtual universe of training, we assigned this category a higher weight. Training apps are critical to the overall functionality of the unit and your training experience. A smart trainer without apps is a fifty-pound paperweight. They rely on applications and their connections to those applications to control resistance, collect data, and provide an engaging riding experience.
The models we tested use both ANT+ and Bluetooth communication protocols. Why both? Well, the short explanation is that most smartphones are not ANT+ enabled, but they do have Bluetooth, so trainers need Bluetooth connectivity for mobile apps. Many computers and tablets also use the Bluetooth protocol, so enabling Bluetooth can provide an adaptor-free method of communication for web-based applications like Sufferfest, TrainerRoad, and Zwift.
You'll want to check out the capabilities of the third-party programs. Zwift, for example, didn't initially support native Bluetooth communication for PC/Windows, meaning you had to download the Zwift Companion mobile app to use your phone as a bridge. Zwift has since fixed that issue and continues to punch up.
If you do run into trouble with Bluetooth compatibility, an ANT+ connection will allow you to communicate with any device by simply plugging an ANT+ dongle into one of the USB ports. Dual communication protocols provide the easiest connection regardless of what type of display device you're trying to use.
The other portion of the category is power accuracy. Smart trainers base resistance on power measured in watts. Each employs a power meter that measures power output. The most accurate way to do this is to read power at the hub, which is the method utilized by direct drive trainers. Tire drive models read power farther down the chain at the drum/resistance unit interface and thus do not offer the same level of power accuracy. Tire drive trainers must contend with more variables when measuring power, primarily the effect that tire drag has on the reading. As a tire heats from friction, the rolling resistance changes, as does the air pressure within the tire. The combination of both factors affects rolling resistance. Because of this, tire drive trainers inherently provide a more variable and less accurate measure of power.
The Tacx Neo 2T Smart and Wahoo Kickr outscored all other products we tested in this category. ANT+ FE-C and Bluetooth Smart communication protocols made for easy connections to the Tacx and Wahoo Fitness smartphone apps and third-party applications. Some of our testers described the Kickr as the Apple of the smart trainer world due to its intuitive and straightforward smartphone application that incidentally works equally well with both IOS and Android devices. The Neo training app, however, was slightly less glamorous and could have used a bit more interactivity, but it connected across apps and platforms without issue.
Unique to the capabilities of the Tacx Neo 2T, though, is a pedal stroke analysis. This feature allows you to see the power and efficiency of each leg during any given workout to help you further understand your strengths and identify areas for improvement. Your one freeloading leg no longer has a place to hide. However, to utilize this feature, you must use the Tacx app, which isn't our favorite of the bunch. Tacx also looked to the future with this model, adding extra memory to make space for software updates and new features in the future. As bike trainer technology continues to improve every year, we think this is a very smart move.
Power accuracy in both models is also excellent, rivaled only by the Saris H3 Direct Drive. We tested all of the products against a Quarq crank-based power meter and Garmin Vector 3 pedals and found a variance of less than one percent with all three models. The Kickr Snap is the best scoring tire drive model, equaling its direct drive counterpart on ease of connectivity. Power accuracy drove the Kickr Snap's overall score down, with variance in the 5% range.
Lower scoring products suffered from less intuitive native applications. Their power accuracy also tended to increase significantly. That said, we welcome the lower end of the market adopting the dual standard communication protocols of ANT+ and Bluetooth, something that wasn't nearly as ubiquitous just a year ago.
This measure might seem like it favors roadies—and it kind of does—but even the grittiest mountain biker is going to get annoyed if their trainer feels like your brake is rubbing or it's lagging hills, or you're missing sprints because it takes too long to respond when you're kicking out watts. For this measure, we mostly look at the smoothness of the resistance unit's physics and responsiveness. Does it feel like the trainer is rolling out when you coast, and the power you put in is appropriate to get back up to cruising? Is it responding the right way? Are the climbs natural or lumpy? Is the trainer adjusting as fast as it needs to or maybe too fast to feel natural? We've never rolled up a hill and had to immediately start putting out 400 watts to stay upright - even on 25% grades, the real world gives you a few seconds to process your emotions and shift down to the sad spinny gears for the pain to come.
Road feel ranks right up there in importance with connectivity. The best simulate the sensation of riding on the road. Poor quality models lack the feeling of inertia you get when riding out on the road. Achieving a good road feel is a complicated feat of engineering. Standard and smart models deliver a good road feel in different ways.
There is a strong correlation between flywheel weight and the sensation that the user gets when spinning the cranks. In general, the heavier the flywheel, the better the road feel. A heavy flywheel mimics the inertia felt when riding outside. You will notice with an inferior quality product the sensation of resistance in the pedaling dead spot during the back half of the pedal stroke. When riding on the road, the forward momentum of the wheels carries you through this spot, and it is not noticeable except on steep climbs. Models with poor road feel give the rider the sensation of being on a perpetual climb.
Smart trainers are a bit more complicated than standard fluid ones. The response to the control protocol from the application determines road feel in combination with the flywheel, or virtual flywheel in the case of the Tacx Neo 2T Smart. During testing, we used a test to determine how long the flywheel would spin once pedaling stopped from 200 watts at 20 mph. We tested the lowest resistance setting on the smart trainers using the native applications.
Those with the longest rollout time usually also offered the best road feel when used in SIM mode. The major exception to this rule was the Neo 2T Smart, using a unique magnetic electromotor to perfectly simulate the road, even going so far as to replicate downhilling, yet its rollout time is only 21 seconds. Returning to the trend, the H3 Smart had the longest rollout time at 2:30, and also has the heaviest flywheel of any model we tested.
Our testers found the Saris H3 Direct Drive to provide the best road feel among traditional flywheels across a range of applications both native and third party. It would be easy to assume that the flywheel weight is the only factor at play, but the complex magnetic resistance units and how they interpret the data fed to them by the applications also plays a critical role.
When it comes to fluid trainers, the flywheel weight makes all the difference. The Wahoo Fitness Kickr Snap has a 10.5-pound flywheel and also provides the best road feel for tire drive trainers. With that said, the top-scoring Tacx Neo 2T Smart blows it out of the water.
Trainers are inherently noisy machines. The drivetrain alone makes about 35 or 40 decibels, so it's really hard to find something that's going to be silent. You're spinning chains and gears against something whose job it is to provide the same sort of resistance as a road or mountain trail. There are just too many moving parts vibrating and fancy things like electric motors to be silent. Despite that, we do measure this because it does make a difference, particularly in close quarters or when cohabitating with people we don't want to disturb.
You might not be surprised to find that there's generally a premium on quietness. A lot of extra engineering has to go into reducing machine vibrations and the friction that make the noise. When we test these, we'll take a few measurements around the bike to get an idea of how the noise is spreading, but we go with the measurement taken in front of the rider. We'll spin up to 20mph and try to keep power at about 220 or 230 watts and 90 RPMs to keep all of the inputs constant.
The quietest we tested is the Kickr Snap which put out 54.5 decibels at 20 mph and 230 watts. The Kinetic Road Machine Control is the second-most quiet tire drive model we tested. The Saris H3 was the quietest direct drive trainer in our tests at just 55.3 dB, and the Tacx Neo 2T came in at 57.8 dB.
When assessing the overall quality of design, we took several factors into account, including durability, stability, adjustability, and wheel and hub compatibility. No matter the price range of the machine you end up buying, you're going to want something that will last a good long while, including everything from kicks and drops to years of sweat and minimal upkeep. And, of course, you want to know if your big 29er is going to fit on this thing that you only see road bikes on before you buy it. We take all of this into account under design.
Durability and Stability
Is this thing going to last? Am I going to tip it over if I go too hard on a sprint? Am I going to break this thing? Is this thing going to break my favorite two-wheeled toy? These are some of the questions we had during testing. We found the heaviest models to be the most stable during use, but it should be noted that we never felt at risk of tipping over with any trainers during testing. The Saris H3 is a standout product with a fully enclosed design. The resistance unit and flywheel are all protected from exposure to sweat and damage by the plastic shell. The legs have a 19.5" footprint when open, providing excellent stability when combined with weight. Other standout products include the Kinetic Road Machine | Control and Kickr Snap that both have tubular steel frames that provide great durability and stability.
Both the H3 and the Kickr have adjustable legs to accommodate an uneven floor. The Kickr can also adjust the trainer's height to accommodate different wheel sizes to maintain a level bike position without the use of a wheel block.
Wheel and Hub Compatibility
Direct drive models have the advantage here because they do not rely on the rear wheel to drive the resistance unit. The H3 Smart is compatible with both 130 and 135mm quick-release frames, as well as 142 and 148mm through axle frames using adaptors. Most other high-end models also support these expanded axle sizes, but you might need to purchase the adaptors separately. This makes the machines compatible with almost any type of bike available: road, cyclocross, or mountain. The tire drive trainers we tested will work with thru-axle bikes as well but require adaptors, and we recommend you use a slick tire rather than the knobby you probably have on your off-road machine.
Along with the Neo 2T, the Saris H3 and Wahoo Fitness KICKR are the highest scoring products overall for design. Excellent durability, stability, and a well-thought-out design set them apart from the competition. Among the tire drive models, we are most impressed with the Kinetic Road Machine | Control and Saris Fluid 2.
We are all crunched for time, and any time lost setting up your trainer could have been spent putting in quality training time. We broke this metric down into two primary areas for consideration, physical setup and tech setup.
Physical Set Up
We spent a lot of time with these trainers and became intimately aware of the setup procedure and related quirks of each unit. From folding out the support legs to attaching the bike, they all have their pros and cons. Overall, we found that direct drive models are the easiest to set up on a daily basis. Despite the need to remove the rear wheel for use, there is no need to mess with tire pressure or drum tension on the rear wheel. With tire drive trainers, the rear wheel does not need to be removed, but you will have to swap out your skewer before mounting the bike and you'll see more tire wear than normal. Also, tire pressure needs to be adjusted before each ride, and the drum tension on the rear wheel also needs to be set up just right.
Pairing and Applications
All of the smart models we tested require the user to download the proprietary application before use. The manufacturer's application allows you to update the firmware before use. The other reason you need to download the native application is for calibration, except with the Tacx Neo 2T Smart, which comes pre-calibrated. All of the other smart trainers we tested require some calibration before initial use and ongoing calibration after that. Without calibration, power measurement will not be accurate. As a result, resistance will be out of balance to your output. The applications for each trainer are easily found in the App Store on both IOS and Android phones. Once downloaded, you will need to follow the instructions within the application to pair your trainer. We found the Wahoo Fitness application to be the easiest and most intuitive to use, with the Saris CVT mobile application coming in a close second.
Calibration, quite frankly, is a pain. Tire drive models require calibration before each training session to account for tire pressure and drum tension differences from ride to ride. Even a quarter turn on the tensioning knob can cause a huge variance in power readings. Ideally, calibrate tire drive trainers following a 10-minute warmup period to account for changes in resistance related to heat build-up. Direct drive, on the other hand, only need to be calibrated every 30 days. This is a huge advantage that will save you an average of 10 minutes with every session. That time adds up over a week of training; we could all be doing something more productive than calibrating a trainer. Only the Tacx Neo 2T Smart never needs calibration, the ultimate regarding convenience. Also, once it's paired with applications, there's no further upkeep required - not to mention the Tacx app, while not as interactive as Zwift, does provide a ton of great training and support while giving you real-world cycling videos, which is pretty cool.
How easy is it to move around? Stationary models are a great option for pre-race warmups, and you may even consider closing the office door for a quick lunch session if you are really serious about training. Even if you never plan to travel with your bike trainer, you will likely need to move it around your living space. Few of us have the luxury of a dedicated space for indoor training, so putting it away after a workout is standard practice. We took several factors into account when ranking products; weight, ease of carrying, storage size, and the ability to operate without electrical power.
This is one area where the smart direct drive trainers do not outscore the lower-priced tire drive models. There are loads of reasons to choose a premium model over a basic unit, but portability is not one. The direct drive models we tested weigh between 30 to 50 lbs. Heavier flywheels, magnets, and electronics all add up to a good ride, but they are not easy to move around. Surprisingly, we found the heavier direct drive H3 Smart and the Kickr to be easier to move than lighter weight smart models like the Kickr Snap. This is due to the well-designed, built-in carrying handles found on both units and compact folding. But generally, tire drive trainers have an advantage in this measure because they are less weight than the direct drive models. Models like the Tacx Neo 2T are awkward to carry, given their weight and precarious handholds.
Testing and thoroughly reviewing bike trainers is considerable work, but our reviewers are bike geeks and more than up for the task. We spend a good deal of time reading and analyzing each bike trainer before we even make a purchase, just like you. After assembling each model and spending dozens of hours atop each machine, we develop an in-depth understanding of each model's capabilities, which we share with our readers. We hope this review and our recommendations prove helpful to your bike training goals and aspirations. Good luck out there, and keep riding.
— Ryan Baham and Curtis Smith
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