REVIEW – When the pandemic drove everyone out of the gyms and into their houses, in-home fitness systems like Peloton took off. Everyone seemed to have one, which might explain why, for a while, they were so hard to get. And they were expensive. Peloton bikes are nice, but they are really just a stationary bike that reports key metrics like power (how much energy you produce, watts) and cadence (how fast you pedal, in rpm). Could you recreate that same basic experience with a non-peloton bike that reported those features? And could that bike do other cool stuff like adjust the resistance on its own? The answer is yes, with a few caveats. Let’s check out the RENPHO AI Smart exercise bike.
What is it?
The RENPHO AI Smart exercise bike is a smart stationary bike and app ecosystem that uses AI to customize workouts to your fitness and ability. It also works with other apps like Peloton, Zwift, and Trainer Road.
What’s in the box?
- RENPHO AI Smart exercise bike
- Parts and tools to put the bike together (don’t worry – it’s not hard)
- AC adapter
- Quick-start guide
- Smart Technology: RENPHO AI Gym App – iOS and Android
- Third-party app connectivity: FTMS Bluetooth
- Third-party app control: Kinoma, Zwif, FulGas, Rouvy, XERT, Wahoo Systm (yes, it’s spelled that way)
- Resistance type: Smart Motor Damping
- Resistance functionality: Automatic and manual resistance
- Power Accuracy: ≥90%
- Power range: 0-1000W（Peak)
- Gears: 80 (the bike does not have actual gears – this is simulated)
- Metrics: Real-time RPM, Power, Cadence, Resistance, Calories
- Wireless firmware updates: Yes
- Frame: Carbon structural steel
- Size: 49 inch(Height) x 20 inch(Width) x 40 inch(Length)、
- Seat: Universal Seat Cushion Standard Dual-Rail Mounting and airflow system 8 inch(Width) x 10.5 inch(Length)
- Pedals: Adjustable Pedal Straps
- Tablet Holder: Up to 8.46 inch
- Adjustability: Handlebar: range 32.5 inch – 41.3 inch Saddle fore/aft : range 0 – 3inch Saddle height: range 32.5 – 41.3 inch
- Crank Length: 6.7 inch
- Q factor: 6.3 inch
- Calibration: Factory Set
- Power required: 120V household power
- Operating Temperature: 41-122°F
- User Requirements: Height range: 4′11″ – 6′0″ (official specs say 6’5’’, but this is impossible)
- Weight maximum: 265 lbs
The hardest part of the RENPHO AI Smart exercise bike assembly is just getting the bike out of the box. It’s very well packaged and protected, but it’s a heavy box to move around. Having a buddy helps.
Once you get the box to where you want, you really just flip it upside down, cut around the bottom, and lift the box off. Then you pull the packaging away, separate the parts, and follow the simple instructions using the tools provided. All told, it took me about 30 minutes from unboxing to riding. The included tools are adequate for the build (just two hex wrenches, and an open end wrench for the pedals). The threads of the bolts all have threadlocker on them, which allows for a stable and safe build, but can make it hard to screw the bolts into their holes. I was concerned that I was crossthreaded a few times, but after some double and triple checking, I chalked the resistance up to the threadlocker. The bolts went all the way in and seemed pretty secure.
Design and features
The RENPHO AI Smart Exercise Bike is physically similar to most stationary bikes out there. It’s highly adjustable, with the seat height, seat placement (fore, aft) and handlebar height all being adjustable without tools.
There is a stable holder for a phone or tablet, and a USB port right on the stem to power your device while you work out. This was a nice surprise because I could find no mention of this USB port in any of the documentation for the bike. A water bottle holder is also included. The phone/tablet support is covered with some miracle substance that really grips your device, but does not seem sticky to the touch. I don’t know what it is, but it works really well to securely hold your device.
The RENPHO AI Smart Exercise Bike is controlled by a large metal dial in the center of the stem, with a simple digital readout in the middle. Adjustments are made by rotating the dial, and confirmation is made by tapping the screen. It’s a simple and efficient system. The display can change based on what you are doing and what apps you are using, but the basic display switches between resistance (0-40 N⋅m), power (watts), cadence (rpm), time, and Bluetooth status.
The bike is capable of measuring and reporting via Bluetooth power and cadence, and can also have the resistance controlled by an app. This is handy during a workout. If the workout wants you to produce 170 watts, it will adjust the resistance to ensure that happens. Power is a function of how fast you pedal, and how hard you pedal. Pedal faster, and the resistance will be reduced. Pedal more slowly, and the resistance will increase. The bike controls it all depending on what app you are using.
The included (free for life!) AI Gym app is very well done, but not quite as engaging as other apps designed for at-home exercise. The app does easily connect to the bike (via Bluetooth) and supports bike firmware upgrades, a few of which occurred during my testing. The app is able to tailor the workouts based on your age, ability, and fitness level, after giving you a basic fitness test on the bike to start. The fitness test ramps up the resistance every minute until you get to a point where you can no longer pedal. It can then create a customized fitness plan, week by week, to help you meet your goals. It also uses that information to scale the resistance to every workout and challenge course in the app. So the fitness test is pretty important. It’s also important that you re-do the fitness test occasionally as your strength and endurance increase. It takes 10-15 minutes.
The app includes over 70 different videos and courses, including free ride, power course, video course, and challenge. Free ride is where you just ride and you get a little display showing you all your stats. But you’re in complete control.
Power course is where you follow a predetermined workout (lots to choose from) and the bike adjusts the resistance for you to make sure you hit the targets.
Video course is similar to power course, but you have a live (recorded) instructor, much like Peloton or an in-person spinning class.
And challenge is where you actually ride a real road, with a video of what that would look like. When you get to a hill, the resistance ramps up, and when you get to a decent, the resistance lets off. It’s very realistic.
The overall performance of the bike and the app ecosystem is quite good, with two big caveats. First, the RENPHO AI Smart Exercise Bike is too small for anyone over 6 feet tall. The specs say the bike is suitable for someone up to 6 foot 5 inches, but that is impossible without compromising good bike fit. I am 6’1 and it’s too small for me. Good bike fit includes fully extending your leg at the bottom of the pedal stroke, keeping your knee barely bent. Without raising the seat above the “stop here” point, this is impossible for me, even barefoot. Riding a bike with the seat too low reduces overall power generation and can be really bad for your knees. So if you are over 6’ tall, this bike is unfortunately not an option. But my 5’3’’ wife loves it.
The second caveat is the resistance occasionally does really strange things. The resistance on the bike is electronic, and is controlled either manually, by rotating the dial on the stem, or automatically by whatever app you are using. When using the bike manually, the resistance starts off at 10 N⋅m, which is pretty easy. If you lower it, it gets easier, until you get to around 3.5 N⋅m, when it suddenly gets VERY hard. Turning the knob doesn’t so much to fix the problem. To get out of this situation, it seems that you have to stop pedaling, pedal backwards a few strokes, and then there is a noticeable “thump” and the resistance goes back to normal. The problem mostly occurs in the lower ¼ of the resistance band. Staying above this generally avoids the problem, but then you can’t use the lower ¼ of the resistance.
Another oddity with the resistance occurs when using the app. The resistance will randomly turn off for a few seconds at a time. This problem actually made it hard for me to complete the fitness test on the bike, since it kept failing me for individual resistance intervals. While these resistance issues do not make the bike unusable, they are very annoying and make for an unpleasant user experience. I am hopeful that firmware updates in the future can fix these problems.
A bright spot with the bike is the AI Gym app. It’s very well done, free (!!), and has a lot of variety. It works well with the bike and provides very solid workout opportunities with a lot of variation. I hope RENPHO continues to add different classes and courses to the app to keep things fresh.
What I like
- Good hardware (unless the goofy resistance is a hardware issue)
- Well packaged, easy assembly, tools included
- Very stable, and easy to move around with wheels on the front
- Great app with lots of variation in workouts and courses
- A good value for a bike that measures and broadcasts power and cadence
- USB port included for charging your device
- It works with other apps like Peloton and Zwift
What I’d change
- The bike is too small if you are over 6 feet tall. Make the seatpost longer.
- Resistance problems need to be solved soon, hopefully through a firmware update
For the price, the RENPHO AI Smart Exercise Bike is a good value in a stationary bike and app ecosystem. The fact that the app is so good and free is impressive. I just hope the bike can be improved with a firmware update. But if you are over 6’ tall, you’re just out of luck. I think RENPHO could fix this problem by including a longer seatpost, but we’ll have to see about that. Overall, I am generally satisfied with the bike (although I can’t use it because I’m too tall), and very impressed with the app.