| Unit | Size | Supported weight | Resistance | Console | Warranty |
|---|---|---|---|---|---|
Sunny SF-RB4953 Check Discounted Price | L:57" W:25" H:45.5" | 275 lbs | Manual magnetic, 8 levels | Time, Distance, Speed, RPM, Calories, Pulse, Scan, Goals, Recovery, BMI | Frame: 3 years Parts: 180 days |
The Sunny Health & Fitness SF-RB4953 is a superior version of the Sunny SF-RB4806. It features a sturdier frame, a greater weight capacity, and better ergonomics. But nonetheless, it still is a manual magnetic recumbent bike without preset programs on the console.
Key Features and Specifications
- Assembled dimensions: 57L x 25W x 45.5H inches (145L x 63W x 116H cm)
- Assembled weight: 74 lbs (33.5 kg)
- Weight capacity: 275 lbs (125 kg)
- Seat: Adjustable
- Resistance: Magnetic, 8 levels
- Console: Time, distance, speed, RPM, calories, pulse, BMI, recovery, goals, scan
- Warranty: Frame 3 years / Parts 180 days
Frame construction
Although the Sunny SF-RB4953 features a sturdy frame with a construction that reminds at least of a 
light-commercial model, it still is a recumbent bike made for home use only. Its frame is made of steel tubing featuring a one-piece base frame with the seat supporting bars directly welded to the base bar for extra sturdiness. All the steel bars in the bike’s frame are coated with a corrosion-resistant paint finish. The color used is light gray, this being the only color available for this particular Sunny exercise bike. The ABS covers of the drive and resistance mechanism are also gray to match the rest of the bike.
The fully assembled bike isn’t extremely large compared to other fitness machines. It is approx. 57″ (145 cm) long, and 25″ (63 cm) wide. Not only that, its net weight is 74 lbs (33.5 kg) which is twice the weight of the average road bike. This weight adds stability. Plus, the bike’s rear base bar integrates a set of adjustable levelers.
Considering that it weighs 74 lbs (33.5 kg), the transport of the boxed unit should be done by two people. But on the other hand, once the bike is assembled, it can easily be moved via the small wheels integrated into the front base. By lifting the bike from its rear base and using the transport wheels, you will only be handling approx. 35% of its total weight.
The bike has a step-through design. Although this may seem to be an insignificant feature, it can be quite a plus especially for users with certain disabilities. It considerably eases entry and exit so you don’t have to raise your feet too high to step over the frame or the drive and resistance box.
Seat and handlebars
The Sunny Health & Fitness SF-RB4953 is equipped with a large seat. The seat pad is approx. 10″ (25 cm) 
deep and 16″ (40 cm) wide so it offers plenty of contact surface. Both the seat pad and the backrest integrate approx. 2″ (5 cm) of foam cushioning for extra comfort. They’re also contoured to provide a better positioning for the user.
The seat is adjustable. It is attached to an oblique rail system offering multiple adjustment positions. It’s designed to accommodate users with an inseam between 30″ and 38″ (76 – 96 cm). In other words, the bike can be used by persons between 5’2″ and 6’4″ (157 – 193 cm). It’s also sturdy enough to support users up to 275 lbs (125 kg).
The seat’s adjustment system is lever-based. This is quite a plus as you can adjust its position while you are seated. Other exercise bikes have a knob-based adjustment system and in most cases, when you need to adjust the seat, you have to step off the bike.
The Sunny SF-RB4953 features two sets of handlebars, one for the seat, one on the front. This is also a plus, as some recumbent bikes such as the Exerpeutic Gold 525XLR for example, don’t have the front handlebars.
The seat handlebars are equipped with metallic pulse sensors. They’re non-adjustable, as they attach via screws directly to the seat frame. Their grips are pretty wide apart (at least 22″) so most users up to 275 lbs (125 kg) should fit.
The front handlebars have fairly long grips as well. They do not have EKG sensors as the seat handlebars. They’re also non-adjustable, but the front mast of the bike is angled towards the user. Therefore, holding on to the front handlebars as you pedaling doesn’t require an awkward posture. Both handlebar sets feature rubberized grips for extra comfort.
Resistance and drive
The Sunny SF-RB4953 recumbent exercise bike is equipped with a manual magnetic resistance system. 
This means it cannot adjust the pedal resistance automatically. It also doesn’t need a power adapter or an external power source. The only power source you will need for the console is a set of two AA batteries.
The bike’s resistance system consists of a magnetic brake which is connected to the tension knob on the front tube of the bike through a steel cable. When you turn the knob, the brake moves closer or farther from the flywheel which results in more or less pedaling resistance.
The bike makes available 8 levels of resistance. The first one delivers a fairly light pedaling difficulty, while the 7-8 settings promote a more intense training regimen and simulate a hill climb.
The bike’s internal flywheel is perimeter-weighted. This means it provides a bit of extra inertia. Its exact weight is not specified, but since it’s not a spin bike, it probably doesn’t weigh more than 20 lbs (9 kg).
The flywheel is bi-directional. In other words, it permits reverse pedaling. However, you cannot coast on the bike, and when pedaling in reverse, the resistance remains constant, given by the selected difficulty setting.
Like most other exercise bikes with a magnetic resistance system, the Sunny SF-RB4953 is equipped with a belt drive system. This means you don’t have to lubricate its transmission. It also promotes a very smooth and quiet pedaling motion.
Last but not least, the bike’s crankset is a 3-piece part. It features steel crank arms, but since it’s a recumbent bike, it’s definitely not made to support standing up pedaling. The pedals are plastic made with a metallic core. They’re also self-leveling and have adjustable straps.
Console
As we’ve mentioned above, the Sunny Health & Fitness SF-RB4953 recumbent bike doesn’t have an automatic
resistance system. This means its console doesn’t have preset programs. Also, it’s battery-powered, featuring a self shut down function after a few minutes of inactivity on the bike. When in idle mode, it shows clock, calendar, and room temperature.
The console has a multi-window LCD display (without backlight). It shows time, distance, RPM, speed, calories, and pulse. Speed and distance are shown in English units (MPH, miles). The console unit cannot be set to metric units. Also, the pulse reading function only applies to the sensors integrated into the seat handlebars. The console is not telemetric and cannot read your pulse from a wireless HR chest strap.
The console offers goal settings for time, distance, calories, and pulse. If a goal is selected for time, distance, or calories, the display counts down from the selected value until it reaches zero. If a goal is selected for pulse, it will beep when you reach the desired goal.
A BMI and a Recovery function are also available. The BMI function gives you the possibility to calculate your body fat percentage. For this, the console will prompt you to input your height, weight, age, and gender. The Recovery function counts your pulse at the end of the workout and based on the pulse cooldown, it will provide you with a fitness rating between F1 – excellent, and F6 – poor.
Two other notable console features that we must mention here are the tablet holder and the HR zone sticker. The tablet holder consists of a small shelf under the display; it’s designed to accommodate any tablet. However, the console does not have a sound system or a USB port for charging your phone or tablet. The HRC sticker shows the heart rate zones that you should aim for depending on your age. Most bikes have this diagram in their manual, but not on the bike, so it’s a plus that you don’t have to keep your manual with you all the time if you need to consult it.
Assembly and Maintenance
The main body of the bike comes pre-assembled. You only have to attach the two base bars, the pedals, the seat base, the seat pads, the front upright bar, the console, the two handlebar sets, connect the tension cable, and the pulse cables. This shouldn’t take more than two hours. The manual provides very clear step-by-step assembly instructions. Also, all the necessary tools for assembly are included.
Once the bike is fully assembled, you only have to keep it clean and periodically check for loose parts or bolts. The internal parts don’t need any lubrication.
The Pros
- Sturdy steel frame – can support users up to 275 lbs;
- Step-through frame design for easy access to the seat;
- Adjustable stabilizers on the rear base;
- Transport wheels on the front base;
- Seat handlebars with pulse sensors;
- Front handlebars included;
- Cushioned and contoured seat and backrest;
- Lever-based seat adjustment system;
- Quiet magnetic resistance system;
- Adjustable resistance offering distinctive 8 levels;
- Weighted pedals with adjustable straps;
- Exercise meter that can track time, distance, RPM, speed, calories, and pulse;
- Goal settings for time, distance, pulse, and calories;
- Recovery function;
- BMI function;
- Tablet holder included;
- Heart rate zone sticker on the console;
- Fairly easy to assemble;
- Little to no maintenance required;
- Decent warranty.
The Cons
- No backlight on the console;
- No bottle holder.
Summary
The Sunny Health & Fitness SF-RB4953 is a recumbent exercise bike designed for home use. It features a manual magnetic resistance system with 8 tension levels, a comfortable seat with a lever adjustment system, and a console that tracks the main workout metrics. It also features a pretty sturdy construction and can hold users up to 275 lbs. It’s an excellent exercise bike for light to medium-intensity cardio workouts, muscle toning, weight loss, and stamina development. It’s also pretty affordable and a great alternative to a more expensive commercial-grade recumbent bike.