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Last Updated: January 7, 2021
Exercise Bike Awards: Best Exercise Bike for Interval Training 2021
The NordicTrack s15i is one of our Best Exercise Bikes in 2021. It is also our Best Bike for Interval Training. The s15i has a 14” touchscreen with wide bevel that houses quick touch buttons for both resistance and incline. Like the s22i, this bike has a motor on the rear stabilizer that creates a -10% decline to +20% incline. The s22i features 22 digital resistance levels with manual controls for both on the extension grips. With a fantastic sticker price and lots of great tech, this is a phenomenal buy! We highly recommend the s15i.
Who It’s For: Cyclists looking for an economic studio bike with tech that rivals more expensive models
The s15i includes some great features that make it a good option for new cyclists:
- Economically priced for a great at-home training experience
- The bike is very quiet so you can ride any time of day
- Automated Incline/Decline automatically lifts the bike while you ride
- Includes iFit coaches, classes and outdoor routes for all levels of training
- Comfortable design with three adjustment points so you can find the right fit
- Offers a good combination of features provides new cyclists great tech on an affordable bike
Our Video Review
- Innovative Design Creates +20% Incline to -10% Decline
The +20% incline to -10% decline is a revolutionary feature on a spin bike. A motor on the rear stabilizer and motorized arm under the pedal crank lift and tilt the bike to simulate outdoor grades.
- The combination of this incline feature in addition to 22 levels of magnetic resistance makes the s15i as close as you can get to outdoor riding.
- This feature also significantly increases training variables as you can now combine resistance, speed and incline to create greater climbing challenges.
- Magnetic Resistance is Silent and Digitally Regulated with 22 Levels
- Magnetic resistance is silent and digitally calibrated. It does not cause wear on the flywheel.
- Specific resistance translates into more accurate wattage stats and allows the rider to always find the same resistance at the same setting.
- Resistance can be adjusted manually on the handlebar controls or on the touchscreen.
- When using an iFit or onboard program, the resistance will automatically adjust for you. Manual controls override automated controls when needed.
- Incline and Resistance controls on Console, Handlebar Extension Grips, and Touchscreen
- In addition to the QuickTouch controls on the extension grips, you can easily manipulate resistance and incline on the large 14” touchscreen. QuickTouch controls for resistance are on the right side of the screen and controls for incline are on the left. Comparatively, the larger screen on the S22i does not have QuickTouch controls on the touchscreen bevel — the screen is larger so these preset controls are eliminated. Personally, I like having the numbered controls visible on the screen.
- iFit is included free for the first year
- iFit enhances the overall experience on the s15i. It includes a database of over 16,000 different workouts including both classes and outdoor rides that are constantly updated. iFit is included free the first year and then it is $15/month for one profile or $33/month for up to four profiles. You need a WiFi connection to run iFit.
- 3-Adjustment Points to find the right fit
- The seat can be adjusted forward or aft via the carriage knob. To find the best fit, set the span between the tip of the saddle and the horizontal handlebar grip about a forearm’s length. Rider may increase this span if desired, but don’t decrease it less than that — pulling the seat too close to the handlebars will bring your knees out of alignment and too close to the front of the bike. Knees should be in line with the midline of your forward foot when pedaling.
- The saddle stem moves up and down. Saddle should be about hip height when you are standing next to the bike. The stem post is angled back on the s15i so when you raise the stem, it will move the saddle back slightly. This increases the span between the saddle and handlebars and keeps body position aligned so taller riders’ knees are directly over the pedals. If your knees jut forward during riding, extending past the midline of the foot, it can produce unwanted knee tension.
- Handlebar adjustment up or down on the handlebar post knob. Handlebars should be roughly the same height as your saddle. Set an appropriate saddle height first and then adjust the handlebars to match. More experienced riders can set the handlebars lower, decreasing torso angle, but this is per rider comfort. Do not set handlebars so low that your diaphragm is restricted.
- All adjustment areas (seat post, carriage, and handlebar post) are clearly marked with orange inch measurements so you can find the right position each time.
- Bike has a compact footprint and wheels for moving
- The NordicTrack s15i Studio Cycle is just 61” high and 56” long. It also has front-mounted wheels so you can pivot and move it out of the way when needed. It is a great training option that takes up considerably less space than a home treadmill.
- Steel Frame Construction is Corrosion Resistant
- Large Wheels on the Front Stabilizer make it so you can roll it out of the way
- 4 Leveling Feet under the Stabilizers help keep it stable on the floor
- Streamlined Racing Saddle (can be swapped out)
- Total Footprint: 55.75” Long x 22” Wide x 61” High
- 14” High Def Touchscreen with wide bevel for Incline and Resistance buttons
- White Stat Bar displays: Wattage, Distance, Incline, Calories, Time (metrics are adjustable)
- Two 2” Digitally Amplified Speakers
- Two Water Bottle Holders sit at base of Handlebar stem
- AutoBreeze™ Workout Fan
- Automated -10% to +20% Incline
- SMR™ Silent Magnetic Resistance
- OneTouch™ Controls on Extension Grips
- Digital Resistance with 22 Levels
- 32lb Weighted Flywheel
- Spongy-coated multi-position handlebars
- Saddle and Pedals can be swapped for any standard road bike pedals and seat
- Three points of adjustment for correct bike fit
- Two 3 Lb. Dumbbells are included and sit in a tray just below the console
- Max User Weight: 350 Lb.
- Frame: 10-Year Warranty
- Parts: 2-Year Warranty
- Labor : 1-Year Warranty
In-depth Review of the s15i Studio Cycle
- The base, stabilizers and posts on the s15i are all steel. Handlebars are coated with a soft grip material. Black plastic molding protects intersecting joints and post shafts. Some serious engineering went into designing this bike. Wires and cables are internal, the drive train is quiet, and the frame is surprisingly solid for a bike that pivots up and down.
- Points of Adjustment are well-designed. There are three adjustment points on the s15i to help different size riders find proper bike fit:
- Forward/Aft adjustment on the seat carriage moves the saddle forward and back.
- Up/Down adjustment via the stem post lifts and lowers the seat carriage.
- Up/Down adjustment in the handlebar post lifts the handlebars to the appropriate height.
- You can tilt the seat slightly up or down by loosening the bolt on the seat carriage. Retighten when you find the right angle. This adjustment requires a wrench.
- s15i Studio Bike geometry resembles a road bike. Handlebars are designed to be in line with the saddle. Rather than angle up at a 120 degree angle, the s15i handlebars extend forward parallel to the floor and so riders lean forward while riding rather than sit up. This position might seem uncomfortable initially, but it facilitates greater hamstring and glute engagement as opposed to a repetitively quad-dominant downward stroke. It also more similarly mimics outdoor road bike riding.
FlyWheel: 32 Pounds, Inertia-enhanced
- The 32pound flywheel is a good weight and size. The heavier a flywheel is, the more momentum it will develop as it spins. This inertia keeps the pedal motion smooth. The inertia-enhanced feature on the s15i means the flywheel utilizes this extra rotational energy so you get a clean pedal stroke without any jerkiness as you ride.
- Benefits of Magnetic Resistance:
- No need to replace parts. There are no brake pads or friction points on the belt or flywheel with magnetic resistance. This reduces the need to replace parts that wear out due to friction.
- Magnetic resistance is practically silent. Because there is no contact or friction, the flywheel doesn’t make noise while spinning or braking. Conversely, flywheel resistance from either wind resistance or brake pad contact produce substantial noise.
- Magnetic resistance can be specifically calibrated and measured. This enables the s15i to provide 24 levels of resistance that are always the same.
Saddle: Adjusts forward/aft and up/down. Replaceable.
- Comfort: One area the s15i could use a bit of improvement is in saddle comfort.
- Typically, on an indoor bike you want a narrow, very slightly padded seat with a smooth surface to prevent moisture build-up. A narrow design allows the leg to move freely with each pedal rotation without too much thigh friction from the saddle itself. Overly wide or padded saddles feel better initially, but they are more likely to cause friction sores on the inside of the thigh due to increased surface area.
- The saddle is designed well, but it feels a little stiff. Comparatively, the Peloton bike has a more comfortable seat.
- Compatibility: Saddle can be replaced with any compatible bike seat.
Pedals: Flat with cages. Replaceable
- Included pedals have a flat surface with cages for secure foothold
- Pedals can be swapped out for clipless pedals (road or SPD) if desired
Screen: 14″ Touchscreen
- Size: I like the size of the s15i screen. Although it is slightly smaller than the s22i, it retains the QuickTouch controls on the bevel which are easy to see and reach. The tilting motion makes it so you can eliminate any overhead glare.
- Screen Movement: The tilting motion makes it so you can eliminate any overhead glare. It also swivels 360 degrees so you can stand to the side of the bike while doing weights or other iFit classes.
- Resolution: The screen features crisp graphics and bright resolution. You can adjust screen settings in the touchscreen menu. Resolution is factory set to match a moderate-speed internet, so if you have quick WiFi, turn the resolution up when you set up your bike.
- Touchscreen: Touchscreen capabilities are responsive. Even with sweaty hands or while riding, I found the touchscreen controls to be easily navigable. Occasionally I had to tap something twice, but it wasn’t often or inconvenient.
- Functionality: The combination of good screen size, crisp graphics, and touchscreen capability makes the overall functionality of the touchscreen top notch.
Handlebars: Adjust up/down. Multiple grips
- Design: The handlebars have a horizontal grip bar, tri-position resting loop, and grip bar extensions that angle up gently on either side.
- Comfort: The handlebars are coated with a spongy grip material that is soft on hands and arms. The overall design and comfort of the handlebars facilitates good position while riding.
- Fans: The fans attached below the screen produce good air flow. You can adjust the direction of the fans by tilting the screen. I’ve read reviews about the fan producing a squeaking noise, but I didn’t notice this. My fan is pretty quiet in general.
- Weights: Two, 3 pound weights are included with the bike. These rest on a tray in between the handlebars and screen.
- There is no Tablet Holder or shelf for phone storage. You could try to rest a phone in one of the water bottle cups, but it might bounce out. Best option is to set a phone gently to the side while riding.
- Storeage Cups: Two storage cups are positioned just underneath the handlebars. These will hold a moderate-sized water bottle.
Incline / Decline range
The +20% incline and -10% decline is innovative tech. While most spin bikes use resistance to simulate grade, the s15i will actually pivot to match the grade while you ride. There are three benefits to this:
- You can ride without having to constantly adjust the resistance and incline. One of the complaints I read frequently with other bikes is, if a rider misses a cue or doesn’t hear the trainer, they don’t know what level they are supposed to be working. With the automated incline/decline and resistance in iFit, the bike will adjust for you so you can just ride along without having to constantly listen for the trainer to tell you what to do. iFit coaches inform you what is coming up, but you don’t have to make all the manual adjustments.
- The auto incline/decline feature more closely simulates outdoor riding. Rather than have to create a hill incline, the s15i pivots so you ride up a real incline while the bike selectively increases the resistance to match. This means you can focus on maintaining cadence and proper form rather than be distracted with continual adjustments. It is a much more
- The combination of incline and resistance (as opposed to resistance alone) offers more training variables and more intense strength training. Level 22 resistance on a +20% incline is more challenging than a 22 resistance on a flat road. Thus, the s15i provides greater training combinations and more advanced resistance combinations than standard indoor bikes that stay level.
- 22 Resistance levels offer abundant training combinations. The digital resistance is also consistent each time at each level for more accurate metrics. Magnetic resistance is frictionless and quiet and doesn’t cause as much wear on the bike.
The s15i features onboard workouts that are not a part of iFit.
- Manual Workout: A white track and stat bar display stats and distance. You can manually adjust the incline and resistance to create your own workout.
- Maps: Select from an array of full-color Google map images. Display options include: Street View; Map View; Satelite; and Rotate (which toggles between views). The images update every few seconds as you ride. There is no audio included, so these are a great option when you want to listen to your own playlist or podcast.
- Interval, Strength, Speed, Calorie Burn: Pre-programmed workouts display a graph of the overall routine. The bike will adjust incline and resistance to match your selected workout. These are of varying length and intensity.
iFit is included free for the first year with up to four profiles. The database of over 16,000 options is impressive and the graphics on the outdoor rides are unmatched. Workouts include the following:
- Personal Trainer Led Cycling Classes: These classes are filmed in a studio with a trainer on a bike in front of you and other participants riding alongside. Class options include a range of options such as: Intervals, HIIT, hill climb, calorie burn, sprint sessions, etc. Trainers are engaging and the bike will automatically adjust to whatever the trainer is doing. If you begin a hill climb, your bike will automatically incline for you. Resistance is also automated in iFit. You control your speed. Manual controls on the screen or handlebars will override automation at any time should you need to adjust it. These classes are not live like they are in Peloton; iFit classes are pre-recorded and music is pre-set. But class participants are real people so you feel like you are part of a class. iFit will keep track of your stats for you, but there is no real-time Leaderboard.
- Outdoor Routes all over the world: No other program can compete with the extensive iFit rides all over the world. You can select a route in Bangladesh, London, or even the mountains of Southern Utah. A trainer rides a bike ahead of you while another cyclist rides behind with a camera. You follow along from this perspective so you can see and hear what the trainer is doing. Again, incline and resistance is automated on the bike to match the terrain and grade of the ride. The videography on these rides is impressive. You not only watch from the perspective of the second rider, iFit will also occasionally add a drone shot or overhead view of the city or landscape while you ride. Peloton has a handful of outdoor routes but they are filmed from a drone, not a cyclist, they do not include direction from a trainer and there is no accompanying sound.
- Studio-Based Combo Classes: These include options where you ride for part of the time, get off the bike and do weights or plyometrics, and then ride again. They are filmed the same as the all-bike classes with other participants and background music.
- Studio-Based Classes for off the bike: Other classes such as strength training, yoga, stretching, or even classes for pregnant mothers can be accessed through iFit and watched on your screen or from any computer or tablet for convenience.
- When pedaling: The s15i is remarkably silent. The magnetic resistance doesn’t create much noise at all while pedalling or when braking.
- When adjusting incline: There is a motor noise when the bike adjusts incline, but this isn’t constant and it isn’t too loud. I would compare it to the noise made by a treadmill when it inclines or declines.
- Speakers: The speakers produce good volume, which is nice when riding, but it could be loud to others in the room, especially since the speakers are in the back of the screen. Play around with the volume a little initially to determine where you want to place your bike. Positioning the bike facing a c
orner will mitigate how much volume you project into the room.
Storage / Folding
The s15i does not fold up, but it does have wheels on the front stabilizer. The bike is a bit heavy, but you can pivot it forward and roll it out of the way if needed. It also has a relatively compact footprint so you can slide it alongside a wall or tuck it in a corner. My only recommendation would be to make sure and remove the weights prior to tilting and rolling the bike. I forgot to remove the weights once when attempting to move the bike and they both fell off, barely missing my toe and the screen.
Items of Note
Aside from a slightly stiff seat, I found the s15i to be sturdy and well-designed. You can swap out the pedals and the seat with a different set if desired.