| Unit | Size | Supported weight | Flywheel weight | Resistance | Fitness monitor |
|---|---|---|---|---|---|
Sunny SF-B1876 Check Discounted Price | L:50" W:20" H:47.5" | 300 lbs | 40 lbs | Manual magnetic | Time, Speed, Avg. Speed, Max. Speed, RPM, Avg. RPM, Max. RPM, Watts, Calories, Pulse, Goals, Race program |
The Sunny SF-B1876 is one of the indoor cycling bikes released by Sunny Health & Fitness in 2020. In terms of features, it can be compared with the Sunny Evolution Pro II (the same flywheel weight, the same fitness monitor, the same type of resistance system) but has quite a different design and lacks the horizontal adjustment feature for the handlebar. It’s not a bike made for commercial use but its construction and sturdiness are pretty close to at least a light-commercial spin bike.
Key Features and Specifications
- Assembled dimensions: 50L x 20W x 47.5H inches (127L x 51W x 120H cm)
- Assembled weight: 111 lbs (50.3 kg)
- Flywheel weight: 40 lbs (18 kg)
- Supported weight: 300 lbs (136 kg)
- Seat: 4-way adjustable
- Drive: Belt
- Resistance: Manual magnetic
- Fitness meter: Time, speed, distance, cadence, watts, pulse, goals, race program
- Extras: Bottle holder, device holder
- Warranty: Frame 3 years / Parts 180 days
Frame construction
The Sunny Health & Fitness SF-B1876 features a heavy-duty frame made of steel tubing. It combines
oval and rectangular tubes in its construction. The frame is triangular for maximum sturdiness, with the main tube slightly curved for improved aesthetics.
The bike’s frame is double-coated with a corrosion-resistant and chip-resistant paint finish. The color used is white, with the “Sunny” logo in red. The only exceptions are the seat post, the handlebar post, and the flywheel which are chrome-plated. Of course, the bike also has several plastic parts in its construction. The most notable ones are the coves of the drivetrain and the covers of the flywheel which are made from a durable thermoplastic material.
The bike is pretty bulky in comparison with other models made for home use. However, just like most other spin bikes, it doesn’t take too much space. It is approx. 50″ (127 cm) long, and 20″ (51 cm) wide. It is recommended, though, to leave at least two feet of clearance all around it for ease of access.
The fully assembled unit is quite heavy for an exercise bike. Its net weight is 111 lbs (50.3 kg). This being said, the packaged unit should be transported by two persons. However, once it is assembled, it can easily be moved by only one person. That’s because its front stabilizer is equipped with two large silicone wheels. By using these wheels to move the bike, you will only be handling about 30% of its total weight.
The bike’s impressive weight provides superior stability. You can be sure that it won’t move or wobble even if you engage in a high-intensity spin workout. Plus, both its base bars have adjustable levelers with large rubber pads.
Seat and handlebars
The Sunny Health & Fitness SF-B1876 includes a pretty standard spin saddle. Its internal shell is made
of a sturdy polymer while the top cover is made of a thick layer of high-density foam. It also integrates a layer of cushioning. Plus, its top is contoured with a median groove for improved breathability.
The bike’s seat assembly offers four-way adjustability (up, down, front, back). Its upright post has 9 adjustment holes while the horizontal slider offers several extra inches of front-to-back adjustment. This being said, the applicable user inseam range for this bike is 28″ – 40″ (71 – 101 cm). In other words, the bike should be able to accommodate users between 5’2″ and 6’6″ (157 – 199 cm). It is also rated for a maximum user weight limit of 300 lbs (136 kg).
The bike is equipped with a multi-grip handlebar. It basically offers a standard grip, a close parallel grip, a racing grip, and a climbing grip. If you don’t install the fitness monitor, you should also be able to adopt an aero grip. Unlike the seat, the handlebar is only up-down adjustable.
The handlebar is covered by a layer of high-density foam material to provide a comfortable and secure grip. Its side grips feature stainless steel pulse sensors and the included fitness monitor has a pulse reading function. The handlebar assembly also has a built-in device holder on which you can place your tablet or smartphone.
Drive and resistance
The Sunny Health & Fitness SF-B1876 indoor cycling bike is equipped with a heavy, 40 lbs (18 kg) 
flywheel. It has a perimeter-weighted design for enhanced inertia, which is great for spinning. It is also bi-directional. In other words, you can pedal in reverse on this bike. However, just as for any other spin bike, coasting is not possible. So, when pedaling in reverse, you will get the same resistance as when pedaling forward.
This Sunny exercise bike is equipped with a belt drive system. It integrates a durable, poly-v rubber belt, highly resistant to abrasion and stretching. Since the bike uses a belt, not a chain, its drivetrain does not require lubrication. Also, a belt generates slightly less vibration than a chain.
The Sunny SF-B1876 indoor cycle features a manual magnetic resistance system. This means you don’t need an adapter for it. But on the other hand, it also means that the bike cannot automatically adjust the resistance.
The main resistance element is a magnetic brake connected to the tension knob on top of the bike’s frame. By turning the knob, you can place the magnets on the brake closer or farther from the flywheel which increases or decreases the pedaling difficulty.
The bike does not have pre-determined resistance settings (or clicks). You simply turn the knob until you get the desired pedaling difficulty. And if you’re wondering about the bike’s maximum difficulty, even the most seasoned cyclist shouldn’t be able to maintain a steady pedaling rhythm for more than a few minutes, if the brake is set to the highest resistance possible.
Like most spin bikes, the Sunny SF-B1876 is equipped with a heavy-duty crankset. The included pedals are made of metallic alloy. They are dual-sided; they have toe cages on one side, and SPD clips for spin shoes on the other. They are durable enough to support spin workouts of all types, even if the user is close to the maximum weight limit.
Fitness monitor
The Sunny Health & Fitness SF-B1876 indoor cycling bike includes a fairly decent fitness monitor unit. 
Although it does not have online connectivity, it does offer plenty of features to keep you motivated. It has a 4-window LCD display that indicates speed, average speed, maximum speed, cadence (RPM), average cadence, maximum cadence, distance, calories, time, and pulse. Speed and distance can be set to either metric or English units; they are by default set to MPH and miles. Its pulse reading function only works with the integrated sensors. The unit cannot read your pulse from a Bluetooth device or a wireless chest strap.
The monitor unit offers target functions for time, distance, calories, and cadence. If a target is selected for time, distance or calories, the display will count down from the selected target until it reaches zero. If a target is selected for cadence, the monitor will prompt you to increase your pedaling rhythm if your cadence falls below the selected target and slow down if your cadence exceeds the RPM.
There is also a Race Mode available on this bike monitor unit. This workout mode only allows you to select a target for time and distance. The cadence is variable. So, you will have to beat the computer to the selected distance by basically keeping a higher cadence than it does.
The monitor unit is battery-powered. It uses two AAA batteries which are included. It starts up when you begin pedaling, and also automatically turns off after a few minutes of inactivity on the bike.
Assembly and Maintenance
Most of the bike’s frame comes pre-assembled. The flywheel, the crankset, the belt, and the magnetic brake, and the seat are already installed. You only have to attach the two base stabilizers, the pedals, the handlebar, and connect the fitness monitor. This shouldn’t take longer than 30 minutes. All the necessary tools for the assembly are included and the manual provides pretty clear assembly instructions and schematics.
For maintenance, you only have to keep the bike clean, wipe off the sweat from the frame at the end of the workout, and periodically check for loose bolts and parts. The belt and brake do not require lubrication.
The Pros
- Heavy-duty steel frame – can support users up to 300 lbs;
- Aesthetic design;
- Transport wheels on the front base;
- Adjustable levelers on both base bars;
- Four-way adjustable seat;
- Pulse sensors integrated into the handlebar;
- Device holder integrated into the handlebar;
- Smooth and quiet belt drive system;
- Perimeter-weighted 40 lbs flywheel for improved momentum;
- Frictionless magnetic resistance;
- Dual-sided pedals (SPD clipless on one side, toe cage on the other);
- Performance monitor included;
- Goal settings for time, distance, calories, and cadence;
- Race program;
- Bottle holder included;
- Device holder included;
- Batteries for the performance monitor are included;
- Little maintenance required;
- Really easy to assemble;
- All the tools required for the assembly are included;
- Excellent warranty.
The Cons
- The fitness monitor doesn’t have backlight;
- No front-to-back adjustability for the handlebar (only up-down);
- No online connectivity.
Summary
The Sunny Health & Fitness SF-B1876 is an indoor cycling bike made for home use. It features a heavy-duty frame, with a 40-lbs flywheel, a manual magnetic resistance system, and a fitness monitor that tracks all the important workout metrics. It also has a race program to keep you motivated. It’s a well-constructed exercise bike designed to support any spin workout, great for high-intensity workouts, interval training, stamina development, and weight loss.