Sunny Health & Fitness Magnetic Exercise Bike 44 lb Flywheel
- Maximum Weight Recommendation: 297.62 pounds
- Resistance Mechanism: Magnetic
- Drive System: Belt
- Power Source: Battery
Last refreshed Jun 30, 2026 · Based on the Amazon listing and published specifications, not hands-on testing.
A smooth, quiet magnetic bike that holds up over years of near daily riding, worth the trade-off of double checking hardware after assembly and occasional shipping damage.
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ASIN: B09R5QRVWGModel: SF-B1805SMARTCategory: Exercise Bikes
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Overview
The SF-B1805SMART is Sunny Health and Fitness's belt driven magnetic exercise bike, built around a 44 lb flywheel and a 300 lb weight capacity, with 4-way adjustable seat and handlebars and an optional free SunnyFit app for Bluetooth tracked rides.
Set against that value case are a couple of recurring build issues: cartons that arrive damaged and hardware, pedal cranks or handlebar bolts, that needed retightening after assembly.
- 44 lb flywheel with belt drive
- 4-way adjustable seat and handlebars
- Optional free SunnyFit app with over 1,000 workouts
- 300 lb weight capacity steel frame
Who it's for
Home riders who want a heavy flywheel spin bike without committing to a monthly studio membership. Anyone unable to move an 80 plus pound box alone, or unwilling to check bolts after assembly, should plan for help or a different bike.
Pros and cons
- Smooth, quiet magnetic resistance confirmed over long term use
- 4-way adjustable seat and handlebars
- SunnyFit app costs less than a Peloton subscription
- Steel frame holds up to heavy daily use
- Shipping cartons arrive damaged for some buyers
- Pedal crank and handlebar bolts may need retightening after assembly
- Boxed weight of 80 pounds or more needs two people to move
Performance notes
Owners riding for a year or more describe the 44 lb flywheel and magnetic resistance as smooth and nearly silent even under near daily use, though pedal crank threads and handlebar bolts have needed retightening on individual units to prevent looseness.
Specifications
| Brand | Sunny Health & Fitness |
|---|---|
| Model | SF-B1805SMART |
| Dimensions & fit | |
| Maximum Weight Recommendation | 297.62 poundslower than 66% of 51 exercise bikes |
| Minimum Height | 47.6 incheslower than 68% of 41 exercise bikes |
| Power & efficiency | |
| Power Source | Battery |
| Construction & materials | |
| Material | Alloy Steel |
| Color | Grey |
| Other details | |
| Resistance Mechanism | Magnetic |
| Drive System | Belt |
| Part Number | SF-B1805SMART |
| Recommended Uses For Product | Indoor |
| Special Features | Heavy Duty |
Closest rivals on specs
Schwinn Recumbent Exercise Bike- Minimum Height 47.6 vs 54 inches (-12%)
Frequently asked questions
Does the SF-B1805SMART require a subscription?
No, the SunnyFit app is free to use with the bike according to the listing.
How heavy is the flywheel?
44 lbs.
What is the weight capacity?
300 lbs.