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Deep Dive: The $2,200 Magnetic Days Jarvis Bike Trainer

Indoor aficionados rejoice! Italian brand Magnetic Days has a trainer that is as quiet as it is extremely expensive.

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Review Rating


The smoothest, quietest, lightest, and most expensive direct drive smart trainer we’ve ever tested also comes with unique and comprehensive training software and custom coaching options.


Excellent manufacturing quality

Fantastic road feel without a heavy flywheel

Completely silent, all you’ll hear is your dirty drivetrain

Easy to store and carry

Integrated battery for use where no power is available

Unique training app which includes 12 semi-customized workouts from a Magnetic Days coach



More or less requires a dedicated iOS or Android device—or PC—to operate (when using MD training app)

Must use caution when out of the saddle to avoid tipping if not using the “Roll Bar” for added stability

No ability to adjust height of trainer for different tire sizes


20 lbs



The Magnetic Days Jarvis direct drive smart trainer is probably a smart trainer that you’ve never heard of. The Jarvis, made completely in Tuscany, Italy, has been available in Italy for about 5 years and has recently crossed the Atlantic into the U.S. market. This premium-level smart trainer will probably not replace the Wahoo Kickr or Tacx Neo in popularity anytime soon, but the Jarvis does have some excellent features that will make it appealing to some.

RELATED: Triathlete’s Guide to Buying Gear

Magnetic Days Jarvis: The Basics

There are two elements to talk about when discussing this trainer, the hardware itself as well as the Magnetic Days training software that is primarily used to control it.

The Hardware:

The Jarvis is an elegantly designed and beautifully manufactured piece of equipment. It is constructed almost entirely of steel and aluminum with a bit of carbon (what, your smart trainer doesn’t have carbon??) and a clear plastic cover that covers the belt. The Jarvis weighs in at only 20 pounds, which is less than half of what the Wahoo Kickr and Tacx Neo weigh. According to Magnetic Days, it has a power ceiling of 1850 Watts with a 53/11 at 120 RPMs, a 90% virtual slope maximum, +/-1% power accuracy, and puts out an impressive 15dB at 20mph. The Jarvis’ legs fold in easily, and it uses a built-in handle for portability. The Jarvis is not adjustable in height, so if you use anything other than a standard 700c road wheel and tire, you may need a riser block or some shims to get everything level. It has Bluetooth and ANT+ connectivity and it broadcasts and connects via WiFi to your tablet, smartphone, or PC when using the Magnetic Days training software (Mac desktop OS not currently supported). The Jarvis also features an internal battery and has an on/off switch so that you can use the trainer without plugging it in. It also includes a Shimano 105 11-speed cassette, a heart-rate monitor, cadence sensor, optical shifting sensor, and fittings for either quick release or thru axle bikes—all packaged in a beautiful custom-made wooden box. If you have a hard time setting up your Jarvis, Magnetic Days offers free live support to help get you up and running. While the price is high, you can also choose an option to rent for three months ($500) or six months ($700) with an option to buy and apply that rental fee to the total purchase price.


The Magnetic Days training software is available for iOS, Android, or PC. The mobile versions of the software connect wirelessly, but the PC software can connect wirelessly or via a USB cable. The software uses a training philosophy called HTT which focuses on power, cadence, pedal force, and heart rate. Each Magnetic Days system includes 12  HTT workouts and pairs you with a Magnetic Days coach when you register your system who will customize the workouts to your needs. After your 12 workouts have been completed, you can purchase more workouts if you desire (and continue to work with the coach). The initial workout a rider does is a fairly standard ramp test, and the results of that test are used to calibrate the customizable workouts to your needs. There are also periodics tests performed to track progress and to adjust the workouts as your fitness progresses. While 12 workouts might not seem like much, but these workouts are hard and not meant to be done day after day.  I can see a triathlete doing maybe one or two of these HTT workouts a week for their intense sessions, so 12 workouts could conceivably last 6-12 weeks.

The core of the system is the Magnetic Days HTT workouts, but you can also use the software to do a simulated course (just requires the .gpx file), a workout with manual control over the resistance, or use the software to connect to Zwift.

Magnetic Days Jarvis: The Experience

The Jarvis is incredibly quiet, thanks to its precise and high-quality construction. It does not rattle or serve as an echo box in any way, so all you will hear is the noise from your own drive train. The resistance provided by the unit is smooth and consistent at all speeds, which is surprising given the relatively small and lightweight flywheel. 

Since so much of the Jarvis’ package focuses around the HTT workouts, I committed to giving them a try for a few weeks. I started off with the MD Ramp test which consists of a lengthy warm-up period followed by rising linear power until failure. I was then assigned a dozen workouts from an MD coach—each about an hour long—that were all based on the initial test.  I was warned that the workouts would be tough and to come prepared for each one, and they definitely lived up to that promise. The workouts were very hard, but just doable if I came into them in a fresh state—I was impressed with just how accurate the workouts were in knowing my breaking point from a simple ramp test. I did enter a few of the workouts with fatigued legs or after a poor night’s sleep, and that caused a few epic fails. The workouts were also interesting, as some aspects of the workout were based on maintaining a certain power output but then the basis would switch to pedaling force which was new to me. I found that the combination of power-based phases as well as force-based phases helped to keep things fresh and interesting and tested me physically in different ways. I’ve suffered in the past racing hilly courses when my pure strength was challenged, rather than my ability to put out constant power at high cadence which is generally the way I’ve approached training.  I imagine that this approach to bike training will be really beneficial once I’m back in the hills. It is easy to see how significant gains could be made with long term dedication to this HTT system. 

Magnetic Days Jarvis: The OK

There are a few quirks to this system that are worth noting. If you are planning to operate your Jarvis with the Magnetic Days software, then you will really want to use a dedicated iOS or Android tablet. The tablet will have to use its WiFi to connect to the Jarvis trainer, which means that the tablet can not access the internet while in operation (at least without a workaround). If you like to stream music or watch Netflix with your device while riding indoors you will have to use a separate device from the one that’s connected to the Jarvis. The Jarvis is lightweight and compact—which is great for storage and moving around—but the legs do not span super wide, which means you’ll have to be careful not to tip over on out of the saddle efforts. Magnetic Days sells an optional “roll bar,” which widens the footprint and also supports the front fork in place of the front wheel. We didn’t test this $420 add on, but it would have been a welcome addition, as I had a few close calls.

A staple of just about any training software is the ability to do a workout in manual ergometer mode. In ergometer mode, the user can simply dial in the exact power output that they want to ride with at any given moment, and the smart trainer adjusts the resistance force based on wheel speed. The MD software does have a manual workout mode where the user can adjust the resistance, akin to tightening the brake on a spin bike, but this is not exactly ergo mode. 

Magnetic Days Jarvis: The Conclusions

The Jarvis from Magnetic Days is an extremely high-quality smart trainer and coaching software bundled into one. The price tag puts it in a separate category than its competitors: The Jarvis costs $1,000 more than a Wahoo Kickr and $800 more than a Tacx Neo2T. When you consider that the Jarvis comes with coaching software and 12 coached workouts, the price becomes a little bit more palatable, but the value of this will largely be based on your use case. The HTT workouts provided by this trainer are hard and effective, and we worked with a coach who was a pro triathlete, so no need to worry about workouts suited to a pure cyclist. If you already have a coach and a dedicated training program that you are content with, then you may not find the value in the Magnetic Days Jarvis. Magnetic Days does offer a rental program which allows you to try before you buy, and if you buy, the cost of the rental is credited towards your purchase. 

Over the course of about a month, we performed the ramp test and a few of the HTT workouts, a good deal of manual workouts, and a few Zwift rides. There were absolutely fitness gains attributed to the HTT workouts, but it’s hard to say if they were any more or less effective than other training plans or philosophies. The beauty of the Magnetic Days Jarvis is in the convenience of it all, you get arguably the best direct drive smart trainer and a fantastic training platform and app all bundled together. There are definitely a few quirks associated with the trainer and the app, but once you get comfortable with it all, getting up and running for a workout is fast and easy. If you’re a die-hard Zwifter, you probably won’t find the Jarvis worth the extra coin, but if you are ready to “stop playing” and to “start training”—as Magnetic Days puts it—then this could be a worthwhile investment.