| Unit | Size | Supported weight | Resistance | Fitness monitor | Warranty |
|---|---|---|---|---|---|
Sunny SF-B1970 Check Discounted Price | L:47.4" W:23.8" H:51.2" | 245 lbs | Manual magnetic, 7 levels | Time, Speed, Distance, Odometer, Calories, RPM, Pulse, Scan | Frame: 3 year Parts: 180 days |
The Sunny SF-B1970 is one of the indoor cycling bikes released by Sunny Health & Fitness in 2021. It’s one of the bikes in the Pro Lite series, equipped with a magnetic resistance system and an 18 lbs flywheel. It’s in the same feature range as the Sunny SF-B1918 but has quite a different design and a higher user weight limit.
Key Features and Specifications
- Assembled dimensions: 47.4L x 23.8W x 51.2H inches (120L x 60W x 130H cm)
- Assembled weight: 67.5 lbs (30.6 kg)
- Flywheel weight: 18 lbs (8.1 kg)
- Supported weight: 245 lbs (111 kg)
- Seat: 4-way adjustable
- Drive mechanism: Belt
- Resistance: Manual magnetic, 7 levels
- Fitness monitor: Time, speed, RPM, distance, odometer, calories, pulse, scan
- Warranty: Frame 3 years / Parts 180 days
Frame construction
The Sunny Health & Fitness Pro Lite SF-B1970 indoor cycling bike features a triangular frame but with a new
design; the front fork that holds the flywheel is welded on a lower point on the main oblique bar than for other spin bikes. This lowers the unit’s center of gravity, improving its overall stability. Plus, the bike features a curved rear base bar with three adjustable levelers while the front base bar also has two adjustable levelers which allow you to perfectly stabilize the bike even on an irregular floor.
Needless to say, the bike’s frame is made of steel tubing. Most of the tubes in its construction are oval for improved aesthetics and sturdiness. The main frame is painted white, while the seat and handlebar posts are gray. The flywheel is chrome-plated with side ABS covers.
The fully assembled bike is not too large. It is approx. 47.4″ (120 cm) long, and 23.8″ (60 cm) wide. Its highest point is approx. 51.2″ (130 cm), with the handlebar extended all the way up. Of course, it is also recommended to allow at least two feet of clearance all around the bike, for ease of access.
The bike is not too heavy. Its net weight is 67.5 lbs (30.6 kg). The transport of the packaged unit may require a box carrier but can be carried by only one person. Also, once the bike is assembled, it can easily be moved via the small wheels integrated into its front base stabilizer.
Seat and handlebars
The Sunny Pro Lite SF-B1970 indoor cycle includes a saddle designed for optimal comfort. It is built on a 
heavy-duty nylon shell, featuring a thick layer of foam padding and a durable vinyl cover. It’s not a super large seat, though; it is only 10″ (25 cm) long, and 5.9″ (15 cm) wide. It has a contoured surface and a median groove for improved breathability.
The seat is four-way adjustable (up, down, front, back). Its upright post offers an adjustment span of 10″ (25.4 cm), from 28″ to 38″ (71 – 96 cm). Its horizontal slider adds approx. 4″ (10 cm) of front-to-back adjustment. Therefore, the bike should be able to accommodate comfortably users between 5’0″ and 6’3″ (153 – 190 cm). It is also rated for a maximum user weight limit of 245 lbs (111 kg).
The bike’s handlebar is only two-way adjustable (up, down); it lacks the horizontal slider feature. Its upright post has several adjustment positions, allowing a maximum height for it of approx. 51″ (130 cm).
The handlebar features a multi-grip design. It offers the possibility to adopt an off-road grip, a climbing grip, and a standard grip. It also has a long loop grip in the middle which allows an aero grip or a close grip if you don’t place a tablet on the plastic support cover. The side grips feature metallic pulse sensors and the included fitness monitor has a pulse reading function. And finally, the whole tube of the handlebar is covered by a layer of PVC foam for a comfortable and secure grip.
Drive system
The Sunny Health & Fitness SF-B1970 indoor cycling trainer is equipped with an 18-lb (8.1 kg) flywheel
similar to the VIGBODY HL-M01. The flywheel has a perimeter-weighted structure in order to provide a superior inertia. As we’ve mentioned above, it has a chrome-plating finish with side panels made of ABS plastic.
The bike’s flywheel can spin both ways. However, coasting is not possible as it would be on a regular bike; the pedals continue to spin for as long as the flywheel is spinning. Also, when pedaling in reverse, the resistance remains constant, given by the selected tension level
The bike is equipped with a belt drive system. It integrates a durable poly-v belt designed for superior traction. This type of transmission offers a few advantages over a chain drive. First of all, you don’t have to lubricate it. And second of all, it generates slightly less vibration which leads to a very smooth pedaling motion.
The bike features a durable 3-piece crankset with flattened arms similar to road bikes. The pedals are made of aluminum alloy. They have a non-slip design and toe cages, however, they don’t have SPD elements for spin shoes. Their threads are standard 9/16″, though, so you can always find compatible replacements in case you’ll want to change them.
The bike has a fairly narrow Q-Factor (spacing between the pedals). It is 190 mm which means that your feet will rest on the pedals at a comfortable distance. This being said, a ride on this bike won’t result in any extra lateral stress on your knees.
Resistance system
The Sunny Health & Fitness Pro Lite SF-B1970 is equipped with a manual magnetic resistance system. 
This being said, you won’t need a power cord or adapter for it. However, the bike also cannot adjust the resistance automatically and does not have pre-set programs.
The resistance system consists of a magnetic brake connected to the tension lever at the top of the main frame tube. The brake is plated at the rear section of the flywheel and connects to the lever through a steel cable. Therefore, when you adjust the resistance, the magnets will cover a larger or smaller portion from the flywheel which will result in higher or lower pedaling difficulty.
The main advantage of the magnetic brake is that the magnets do not touch the flywheel. Thus, the pedaling motion is very smooth and quiet. Also, you don’t have to worry about brake pad replacement or lubrication.
The bike’s brake offers 7 tension levels. The lowest level delivers a fairly light workout load, great for recovery training or a workout warm-up. Conversely, the top tension level delivers considerably more resistance simulating a hill climb.
Fitness monitor
The Sunny Pro Lite SF-B1970 includes a similar type of fitness monitor as the Sunny SF-B1918 but also has
a pulse reading function. It features an LCD display (without backlight) that tracks time, distance, total distance, speed, RPM, calories, and, of course, pulse. Speed and distance are shown in MPH and miles; there is no option for setting them to kmh and kilometers or meters. The pulse reading function is grip only. In other words, the unit can only read your pulse if you hold on to the integrated sensors. It is not telemetric and cannot read pulse from a wireless transmitter.
The monitor unit does not have pre-set programs or online connectivity. It only has one button which covers all its functions. By pressing the button repeatedly, you can scroll through the workout metrics and select the one you want to view. You can also select the unit’s Scan Mode which automatically rotates all the metrics showing each one for 6 seconds. And finally, by pressing and holding the button for a few seconds, you can reset all the data to zero, except the odometer.
The monitor unit requires two AAA batteries which are included. It starts up when you begin pedaling or when you push the button. It also automatically turns off if it does not detect any activity on the bike for more than 4 minutes.
Assembly and Maintenance
The bike’s body with the flywheel, belt, crankset, and resistance system, comes pre-assembled. However, the rest of the parts require user assembly. You will have to attach the two base stabilizers, the seat, the pedals, the handlebar post, the handlebar, and the fitness monitor. This may take more than an hour of your time but the process is pretty straightforward. The manual provides clear, step-by-step assembly instructions, and all the necessary tools are included.
Once the bike is assembled, you only need to remove the perspiration that may fall on the frame at the end of the workout, and in general, keep the bike clean. The bike’s drive system does not require lubrication.
The Pros
- Fairly sturdy steel frame – can hold users up to 245 lbs;
- Aesthetic design;
- Transport wheels on the front base;
- Adjustable levelers on both base bars;
- Four-way adjustable seat;
- Contoured, cushioned saddle with a middle cutout for improved breathability;
- Smooth and quiet belt drive system;
- Perimeter-weighted flywheel for improved inertia;
- Frictionless magnetic resistance;
- Durable metallic pedals with toe cages;
- Fitness monitor included – it tracks time, distance, total distance, speed, RPM, calories, and pulse;
- Device holder included;
- Batteries for the monitor are included;
- Little maintenance required;
- Really easy to assemble;
- All the tools required for the assembly are included;
- Excellent warranty.
The Cons
- No goal-setting function;
- The fitness monitor does not have backlight.
Summary
The Sunny Health & Fitness Pro Lite SF-B1970 is an indoor cycling bike made for home use. It is equipped with an 18-lb flywheel, a 7-level manual magnetic resistance system, and a 4-way adjustable saddle. It also included a fitness monitor that tracks the most important workout metrics. It’s a bike designed for spin workouts, high-intensity cardio training, stamina development, and weight loss.