| Unit | Size | Supported weight | Flywheel weight | Resistance | Fitness monitor |
|---|---|---|---|---|---|
Sunny SF-B1805SMART Check Discounted Price | L:50.8" W:23.4" H:47.6" | 300 lbs | 44 lbs | Manual magnetic | Time, Speed, Distance, Calories, Pulse, Cadence, Goals, Race |
The Sunny SF-B1805SMART is one of the indoor cycling bikes released by Sunny Health & Fitness in 2022. It’s basically an improved version of the Sunny SF-B1805 as it includes a fitness monitor, has Bluetooth connectivity, and is compatible with the SunnyFit app. It also comes with a superior set of pedals featuring SPD clips, not just toe cages.
Key Features and Specifications
- Assembled dimensions: 50.8L x 23.4W x 47.6H inches (129L x 59W x 121H cm)
- Assembled weight: 125.7 lbs (57 kg)
- Flywheel weight: 44 lbs (20 kg)
- Supported weight: 300 lbs (136 kg)
- Drive: Belt
- Resistance: Manual magnetic
- Fitness monitor: Speed, average speed, max. speed, cadence, average cadence, max. cadence, time, distance, calories, pulse, race program
- Accessories: Bottle holder, tablet holder, Bluetooth, compatible with the SunnyFit app
- Warranty: Frame 3 years, Parts 180 days
Frame construction
The Sunny Health & Fitness SF-B1805SMART features a heavy-duty steel frame made mostly of rectangular tubing. 
Although it’s not a bike rated for commercial use, it definitely has the sturdiness and construction of at least a light-commercial bike.
The frame has a triangular design for maximum durability. It also integrates a step-up bar; this is the small horizontal tube at the base of the seat tube, right above the crank. Not only that this bar can help with mounting and dismounting, as well as in certain spin workouts, it also improves the frame’s structural sturdiness.
The main frame is double-coated with a rust-resistant and chip-resistant paint finish. The color used is black, this being the only color available for this bike. The only exceptions are the seat post and slider, the handlebar post with its slider, and the flywheel. These have a chrome finish.
Compared with other fitness machines, this Sunny Health & Fitness exercise bike is not too large. However, it is a bit larger than other models. It is approx. 50.8″ (129 cm) long, and 23.4″ (59 cm) wide. Plus, you’ll have to allow at least two feet of clearance all around it, for easy access.
The bike is fairly heavy. It is net weight is 125.7 lbs (57 kg), so the packaged unit requires two persons for transport. However, once the bike is fully assembled, it can be moved easily by only one person. Its front base has large silicone wheels. Also, both base bars have large adjustable levelers.
Seat and handlebars
The Sunny Health & Fitness SF-B1805SMART indoor cycling bike is equipped with a saddle designed for superior comfort.
First of all, it is pretty large, approx. 10″L x 8″W (25 x 20 cm), so it provides plenty of contact surface. It integrates a thick layer of foam padding (approx. 3″) and has a durable faux leather cover that is moisture-proof and easy to maintain. It has a median groove for improved breathability. Plus, it has suspension springs at the rear so it can bend with ease and adapt to your movement.
Another important aspect about the saddle regards its attachment system. It is collar-type, which means you can easily remove it, if necessary. Also, if you will ever want or need to replace it, compatible options are widely available.
The seat is four-way adjustable (up, down, front, back). Its upright post has multiple adjustment positions with an applicable user inseam length between 29.9″ and 40″ (79 – 101 cm). Plus, the horizontal slider adds a few inches of front-to-back adjustment. Thus, the bike should be able to accommodate users between 5’1″ – 6’7″ (155 – 201 cm). It is also rated for a maximum user weight limit of 300 lbs (136 kg).
This Sunny exercise bike comes with a multi-grip handlebar. It offers the possibility to adopt a climbing grip, an aero grip, a cruising grip, an off-road grip, and a close grip. It integrates pulse sensors while the older model doesn’t have this feature. It is also four-way adjustable, its highest point being 47.6″ (121 cm), while the distance between it and the seat can be adjusted between 23″ and 27.8″ (58 – 70 cm).
Resistance system
The Sunny SF-B1805SMART indoor cycle is equipped with a manual magnetic resistance system. This being said, you 
don’t have to connect it to a power source, and you don’t need a power cord or adapter for it. But on the other hand, the included fitness monitor does not adjust the resistance automatically.
The bike’s resistance system consists of a magnetic brake attached to the frame and to the bike’s tension knob. Therefore, when you turn the knob to the right, the magnets cover a larger portion of the flywheel which results in a higher pedaling difficulty. The brake also integrates a small leather pad and you can press the knob all the way down if you need to stop the flywheel from spinning.
There bike’s magnetic resistance system comes with several advantages over a standard friction resistance system. First of all, the magnets do not touch the flywheel, there is no friction, and the flywheel spins freely and quietly. And second of all, the magnets do not require lubrication and they won’t wear out.
The brake doesn’t have pre-determined settings, like other exercise bikes with a magnetic resistance system. You simply turn the knob left or right until you find a difficulty setting that you feel comfortable with. As a general idea, the maximum resistance level is quite a challenge even for the most seasoned cyclists. It simulates a steep hill climb.
Drive system
The Sunny Health & Fitness SF-B1805SMART indoor cycling bike is equipped with a 44 lbs (20 kg) flywheel. It is 
chrome-plated and has protective ABS side panels. It is perimeter-weighted and provides a consistent momentum, great for spinning workouts. It is also bi-directional, so you can pedal in reverse if you want.
The crankset features thick steel arms while the pedals are also made of aluminum alloy. This being said, you should be able to perform any type of spin workout as long as you don’t exceed the maximum specified user weight limit (300 lbs). The pedals have toe cages and SPD elements for spin shoes. Their threads are 9/16″ so you can easily find replacements for them if needed.
The bike’s Q-Factor (spacing between the pedals) is 186mm, which is not too wide. This means that your feet a positioned naturally on the pedals, without being too far apart. This leads to a comfortable ride without extra lateral stress on the knees and ankles.
The bike’s drivetrain uses a poly-v belt, not a chain. This type of transmission comes with a few advantages as well. First of all, you don’t have to worry about its lubrication or stiff chain links. And second of all, the belt generates less vibration than a chain, contributing to the overall smoothness of the ride.
Fitness monitor
The bike comes with a fitness monitor similar to the one included with the Sunny SF-B1852. It features an LCD display divided into four sub-sections. The top one covers the Race program. The 2nd window covers speed and cadence. The 3rd window shows distance and watts, and the bottom window covers time and pulse. Speed and distance are shown in imperial units. The pulse reading function is grip only. In other words, the unit can’t read your pulse from a heart rate chest strap, so you have to hold the sensors to get an HR reading.
The monitor has a Race program and offers the possibility to select workout goals. The Race program is basically a Cadence goal program. If you pedal slower, the Cadence bar will fall under the selected Cadence target so you’ll know that you have to pedal faster. Conversely, if the Cadence bar exceeds the target Cadence, you should pedal slower. The other goal settings are simpler. You can select a target for time, distance, and calories. If a target is selected, the monitor will count down from it until it reaches zero.
The monitor unit uses two AAA batteries as its power source. These are included with the bike. It starts up when you press the Mode button or when you begin pedaling. It also has a self-shutdown function which initiates if the sensor does not detect any input on the bike.
The bike also has Bluetooth connectivity. A QR code is included and you can scan it with your phone to install the SunnyFit app. This app is available for both iOS and Android devices. It opens new features including multiple workout videos, scenic rides based on various locations in the world that sync with the speed of the bike, challenges, and the possibility to track your progress online.
Assembly and Maintenance
The main frame of the bike with the flywheel, the magnetic brake, the crankset, and the belt, comes pre-assembled. You only need to attach the two base bars, the pedals, the seat post, the saddle, the handlebar post, the handlebar, the fitness monitor, and the bottle holder. This shouldn’t take more than an hour of your time. The manual provides clear assembly instructions and schematics, and a basic toolkit is included.
For maintenance, all you have to do is keep the bike clean and periodically check for loose parts. The drivetrain doesn’t need any lubrication.
The Pros
- Durable steel frame – can hold users up to 300 lbs;
- Aesthetic design;
- Adjustable levelers on both bases;
- Transport wheels on the front base;
- 4-way adjustable seat;
- 4-way adjustable handlebar;
- Cushioned and contoured saddle with a large groove in the middle for extra breathability;
- Multi-grip handlebar;
- Pulse sensors integrated into the handlebar;
- Perimeter-weighted, 44 lbs flywheel;
- Heavy-duty crank made for standing up spin workouts;
- Metallic alloy, dual-sided pedals, with toe cages on one side, and SPD clips for spin shoes on the other;
- Frictionless, wear-free, magnetic resistance system;
- Smooth and quiet belt drive, great for apartment use;
- Fitness monitor included – it tracks time, distance, speed, cadence, calories, and pulse;
- Goal settings for time, distance, and calories;
- Race program;
- Bluetooth connectivity;
- Compatible with the SunnyFit app;
- Bottle holder included;
- Device holder included;
- Easy to assemble;
- Little maintenance required;
- Excellent warranty.
The Cons
- The fitness monitor doesn’t have backlight.
Summary
The Sunny Health & Fitness SF-B1805SMART is an indoor cycling bike made for home use. It features a manual magnetic resistance system, a high-comfort saddle, superior micro-adjustability, dual-sided pedals, and a fitness monitor with target settings and a race program. The bike is also Bluetooth-enabled and compatible with the SunnyFit app. It’s a pretty complete exercise bike, great for users of all levels, for high-intensity cardio and spin workouts.