Best for programs and comfort
Sunny Health & Fitness SF-RB4850SMART
FitScore for Exercise Bike Without Subscription
- ResistanceMagnetic, 16 levels
- Max user weight300 lb
- Warranty3 year frame, 6 months p…
- Product weight55 lb
Choose it if you want a backrest, 24 built-in programs, 16 magnetic levels and a 55-lb bike you can roll aside.
Best for hard rides
Sunny Health & Fitness SF-B901SMART
FitScore for Exercise Bike Without Subscription
- ResistanceFriction, stepless knob
- Max user weight275 lb
- Warranty3 year frame, 6 months p…
- Product weight100.4 lb
Choose it if you want a spin position, a 40-lb flywheel, a frame 19.7 inches wide and stepless resistance for hard intervals.
Overall winner for riders who want no subscription: Sunny Health & Fitness SF-RB4850SMART, by 0.1 points (60.5 against 60.4) with the weights of our best exercise bike without subscription guide. It leads on features, durability, comfort and practicality. The Sunny Health & Fitness SF-B901SMART leads on performance and affordability.
Sunny Health & Fitness SF-RB4850SMART wins 4 rounds- Sunny Health & Fitness SF-B901SMART wins 1 round
Product photos from Amazon. FitScore weights are explained below.
Sunny SF-RB4850SMART vs SF-B901SMART: both use the free SunnyFit app and need no membership. The RB4850SMART is a recumbent with 16 magnetic levels and 24 programs; the B901SMART is a spin bike with a 40-lb flywheel. Our FitScore for no-subscription riders puts them a tenth apart.
Head-to-Head Specs
Here are the two side by side. A check mark shows the stronger spec on each line. Check both warranties before you order: the FTC explains how to read a product warranty. The CDC recommends that adults get at least 150 minutes of moderate-intensity aerobic activity a week, which steady cycling counts toward. Harvard Health Publishing lists about 252 calories in 30 minutes of moderate stationary cycling for a 155 lb person.
| Specification | Sunny Health & Fitness SF-RB4850SMARTFitScore 60.5 | Sunny Health & Fitness SF-B901SMARTFitScore 60.4 |
|---|---|---|
| Type | Recumbent | Spin (indoor cycling) |
| Resistance | Magnetic, 16 levels | Friction, stepless knob✓ |
| Flywheel | 6.6 lb | 40 lb✓ |
| Max user weight | 300 lb✓ | 275 lb |
| Size (length × width) | 61.81 × 25.98 in | 61.8 × 19.7 in |
| Product weight | 55 lb✓ | 100.4 lb |
| Rider fit | Inseam 29.9-39.4 in | Inseam 29.1-42.1 in |
| Seat and handlebar | sliding seat | 2-way handlebar |
| Console and programs | 24 programs✓ | Basic LCD console (programs not stated) |
| Bluetooth and apps | Bluetooth, SunnyFit (free) | Bluetooth, SunnyFit (free) |
| Heart rate | Pulse grips | Pulse grips |
| Membership | None needed | None needed |
| Storage and moving | Transport wheels, 55 lb | Transport wheels, 100.4 lb |
| Warranty | 3 year frame, 6 months parts | 3 year frame, 6 months parts |
| Specs won | 3 of 14 | 2 of 14 |
Check Amazon for current pricing and availability.
FitScore Duel
Both scores use the weights of our best exercise bike without subscription guide (how we score). Features (25%) counts most, then performance and durability (20% each), comfort (15%) and practicality and affordability (10% each). The Sunny Health & Fitness SF-RB4850SMART ranks #1 in that guide. The Sunny Health & Fitness SF-B901SMART ranks #2 in that guide. The order flips with other weights: in our best exercise bike for home guide the Sunny Health & Fitness SF-B901SMART scores 62.9 against 62.2 for the Sunny Health & Fitness SF-RB4850SMART.
Key Differences
- Type: Recumbent on the Sunny Health & Fitness SF-RB4850SMART; Spin (indoor cycling) on the Sunny Health & Fitness SF-B901SMART.
- Resistance: Magnetic, 16 levels on the Sunny Health & Fitness SF-RB4850SMART; Friction, stepless knob on the Sunny Health & Fitness SF-B901SMART.
- Flywheel: 6.6 lb on the Sunny Health & Fitness SF-RB4850SMART; 40 lb on the Sunny Health & Fitness SF-B901SMART.
- Max user weight: 300 lb on the Sunny Health & Fitness SF-RB4850SMART; 275 lb on the Sunny Health & Fitness SF-B901SMART.
- Size (length × width): 61.81 × 25.98 in on the Sunny Health & Fitness SF-RB4850SMART; 61.8 × 19.7 in on the Sunny Health & Fitness SF-B901SMART.
- Product weight: 55 lb on the Sunny Health & Fitness SF-RB4850SMART; 100.4 lb on the Sunny Health & Fitness SF-B901SMART.
- Rider fit: Inseam 29.9-39.4 in on the Sunny Health & Fitness SF-RB4850SMART; Inseam 29.1-42.1 in on the Sunny Health & Fitness SF-B901SMART.
- Seat and handlebar: sliding seat on the Sunny Health & Fitness SF-RB4850SMART; 2-way handlebar on the Sunny Health & Fitness SF-B901SMART.
Round 1 of 5
Sunny SF-RB4850SMART vs SF-B901SMART: Resistance and Flywheel
Sunny Health & Fitness SF-B901SMART wins this round
Here is how the two compare on the work the machine does.
Resistance: Magnetic, 16 levels on the Sunny Health & Fitness SF-RB4850SMART, Friction, stepless knob on the Sunny Health & Fitness SF-B901SMART.
Flywheel: 6.6 lb on the Sunny Health & Fitness SF-RB4850SMART, 40 lb on the Sunny Health & Fitness SF-B901SMART.
Performance score in this comparison: Sunny Health & Fitness SF-RB4850SMART 56, Sunny Health & Fitness SF-B901SMART 85.
Round 2 of 5
Capacity, Frame and Warranty
Sunny Health & Fitness SF-RB4850SMART wins this round
Capacity and warranty are the stated measures of build.
Max user weight: 300 lb on the Sunny Health & Fitness SF-RB4850SMART, 275 lb on the Sunny Health & Fitness SF-B901SMART.
Warranty: both list 3 year frame, 6 months parts.
Durability score in this comparison: Sunny Health & Fitness SF-RB4850SMART 54.94, Sunny Health & Fitness SF-B901SMART 50.14.
Round 3 of 5
Fit and Riding Position
Sunny Health & Fitness SF-RB4850SMART wins this round
Type: Recumbent on the Sunny Health & Fitness SF-RB4850SMART, Spin (indoor cycling) on the Sunny Health & Fitness SF-B901SMART.
Rider fit: Inseam 29.9-39.4 in on the Sunny Health & Fitness SF-RB4850SMART, Inseam 29.1-42.1 in on the Sunny Health & Fitness SF-B901SMART.
Seat and handlebar: sliding seat on the Sunny Health & Fitness SF-RB4850SMART, 2-way handlebar on the Sunny Health & Fitness SF-B901SMART.
Comfort score in this comparison: Sunny Health & Fitness SF-RB4850SMART 88, Sunny Health & Fitness SF-B901SMART 70.
Round 4 of 5
Size, Weight and Moving
Sunny Health & Fitness SF-RB4850SMART wins this round
Size (length × width): 61.81 × 25.98 in on the Sunny Health & Fitness SF-RB4850SMART, 61.8 × 19.7 in on the Sunny Health & Fitness SF-B901SMART.
Product weight: 55 lb on the Sunny Health & Fitness SF-RB4850SMART, 100.4 lb on the Sunny Health & Fitness SF-B901SMART.
Storage and moving: Transport wheels, 55 lb on the Sunny Health & Fitness SF-RB4850SMART, Transport wheels, 100.4 lb on the Sunny Health & Fitness SF-B901SMART.
Practicality score in this comparison: Sunny Health & Fitness SF-RB4850SMART 56, Sunny Health & Fitness SF-B901SMART 51.
Round 5 of 5
Console, Apps and Extras
Sunny Health & Fitness SF-RB4850SMART wins this round
Console and programs: 24 programs on the Sunny Health & Fitness SF-RB4850SMART, Basic LCD console (programs not stated) on the Sunny Health & Fitness SF-B901SMART.
Bluetooth and apps: both list bluetooth, SunnyFit (free).
Neither bike needs a paid membership: both pair with the free SunnyFit app over Bluetooth.
Features score in this comparison: Sunny Health & Fitness SF-RB4850SMART 55, Sunny Health & Fitness SF-B901SMART 35.
Who Should Buy Each
Riders who want guided rides without an app plan
Pick the SF-RB4850SMART if the console programs and a supported seat matter most; owners like the back support and the quiet ride.
Riders who want a gym-style spin bike at home
Pick the SF-B901SMART for standing climbs and intervals; owners call it solid and easy to build, and the stock seat is the most common complaint.
Consider Instead
Schwinn 230
If neither fits, look at the Schwinn 230: it offers a higher durability score than the Sunny Health & Fitness SF-RB4850SMART. It ranks #3 in our best exercise bike without subscription guide.
Final Verdict
Overall winner for riders who want no subscription: Sunny Health & Fitness SF-RB4850SMART. Pick the SF-RB4850SMART for built-in programs and a supported seat; pick the SF-B901SMART for a heavy flywheel and a spin-class feel.
Sunny Health & Fitness SF-RB4850SMART vs Sunny Health & Fitness SF-B901SMART FAQ
With the weights of our best exercise bike without subscription guide, the Sunny Health & Fitness SF-RB4850SMART scores higher: 60.5 against 60.4. It leads on features, durability, comfort and practicality, while the Sunny Health & Fitness SF-B901SMART leads on performance and affordability.
No. Both work with the free SunnyFit app over Bluetooth, and both run without any app.
The SF-RB4850SMART. Its backrest, magnetic levels and 24 programs make steady rides easy to start; it is the number one pick in our beginner ranking.
They are the same length, about 61.8 inches, and the SF-B901SMART is narrower at 19.7 inches against 26 inches.
Explore More Exercise Bike Guides
Sunny Health & Fitness SF-RB4850SMART Review
Sunny Health & Fitness SF-B901SMART Review
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