Sunny SF-RB4616 Recumbent Bike | It’s a Reliable Bike!

With the Sunny SF-RB4616 Recumbent Bike, Sunny Health and Fitness keep your workouts on track with an efficient and cost-friendly recumbent bike that is comfortable to use and adequately gets the job done.

The padded seat of the SF-RB4616 is full and adjustable in position. It comes designed in such a way that prevents backaches by keeping your posture upright. With the help of the adjustable handle found on the lower side of the seat you are positioned on, you can adjust the seat forward, backward, upwards, and downwards while sitting.

Right beneath the handlebars, you will find a knob that lets you choose between 8 different types of resistances. The knob is adjustable, and by turning it, you can alter the tension in the knob and subsequently increase or decrease the total resistance. Using this feature, if you increase the resistance, you will have to pedal harder to burn the weight.

The Sunny SF-RB4616 has everything that a reliable and decent recumbent bike could offer. With the eight-level resistances, adjustable chair, heart-sensor handrails, and a display that does its job at tracking readings, you are getting everything and maybe a little more for the nominal price you’re paying for it.

Learn more in my complete review below

Sunny SF-RB4616 Recumbent Bike
Sunny SF-RB4616 Recumbent Bike

Product: Sunny SF-RB4616 Recumbent Bike

Price: For a great deal on this bike, merely go here on Amazon

Warranty: Frame 3 years / Parts 90 days

My rating: 8.5/10

Amazon Affiliate Disclosure: I may earn commissions on purchases made through links in this post.

Details & Specifications

  • Assembled dimensions: 54.4L x 26W x 39.5H inches (138L x 66W x 100H cm)
  • Assembled weight: 59 lbs (27 kg)
  • Weight capacity: 300 lbs (136 kg)
  • Pedals: With adjustable straps
  • Drive: Belt
  • Resistance: Magnetic, eight levels
  • Console: Time, distance, speed, calories, odometer, pulse, SCAN
  • Warranty: Frame 3 years / Parts 90 days

SF-RB4616 Frame construction

The Sunny SF-RB4616 is for home use but does have a durable construction with a steel frame that can hold users up to 300 lbs. The main chassis of the bike is one piece, not two pieces, as for other bikes. This particular aspect leads to an improved overall sturdiness.

All the steel bars within the bike frame come coated with a corrosion-resistant paint finish. The color used is metallic gray, this being the only color available for this unit.

Sunny SF-RB4616 Recumbent Bike

Compared to other fitness machines, this Sunny exercise bike isn’t huge. However, it still is approx 54.4″ (138 cm) long, and 26″ (66 cm) wide. Plus, it is advisable to assign a usage area for it of at least 70″ x 50″ (178 x 127 cm), for safe operation and ease of access.

Speaking of ease of access, the Sunny SF-RB4616 features a step-through design. This type of frame construction promotes an easy entry and exit, which may be extremely important for users with specific disabilities.

The bike isn’t hefty. With the frame fully assembled, it only weighs approx 59 lbs (27 kg). Therefore, it can be put together by one person. Also, its front base features a set of wheels that facilitate its relocation.

Like most recumbent bikes, the Sunny SF-RB4616 offers excellent stability. Plus, its rear bar comes equipped with a set of adjustable polygonal stabilizers. You can rotate any of these two stabilizers to perfectly level the bike. However, it’s advisable to place and use the bike on a rubberized mat.

Seat & handlebars

The Sunny SF-RB4616 features a reasonably large seat. It’s 14.5″ (37 cm) wide, and 11″ (28 cm) deep. Both the seat and the backrest have a 1.5″ (3.8 cm) thick foam padding to provide optimal comfort. The upholstery on both a durable and perspiration-proof vinyl material.

If you’re wondering, the backrest cannot be adjusted independently from the seat. It doesn’t recline, nor can it be positioned lower or higher. It has a very sturdy backbone and delivers comfortable lumbar support.

The whole seat assembly is 2-way adjustable. It is attached to a slider that can move back and forth on its base rail bar. The adjustment system features a lever placed on the right side under the seat. Therefore, you can adjust the position of the seat while you are seated.

Sunny SF-RB4616 Recumbent Bike
Sunny SF-RB4616 Recumbent Bike

The seat’s adjustment span can accommodate users with an inseam between 26″ and 33.9″ (66 – 86 cm), in other words, users between 5’0″ and 6’5″ (153 – 196 cm). Also, the seat assembly is durable enough to support users up to 300 lbs (136 kg).

This Sunny recumbent bike comes equipped with two sets of handlebars. One is attached directly to the seat assembly, and these handlebars incorporate pulse sensors so that the unit’s meter can track your pulse.

The other is connected directly to the console mast. This handlebar set is relatively simple but slightly curved to deliver a more comfortable grip for your wrists. These handlebars do not have pulse sensors. A layer of rubber foam material covers both sets of handlebars.

SF-RB4616 Resistance & drive

This Sunny recumbent exercise bike features a manual magnetic resistance system. This means you don’t have to connect it to a power source. The resistance adjustment is made manually from the tension dial on the console mast.

The console does not play any role in the resistance adjustment; it’s merely a fitness meter that tracks your distance traveled, speed, pulse, etc.

The resistance system consists of a small magnetic brake attached to the dial on the console mast. As you turn the knob clockwise, the magnetic brake will move closer to the metallic flywheel, increasing the intensity of the internal magnetic field. Thus, you will benefit from a higher resistance during pedaling.

There are eight levels of resistance available. The first levels offer a very light workout, great for users who require recovery training. The top resistance levels (7-8) are not too hard, though. They do offer, though, a mid-range resistance that can help you break a sweat if needed.

Like most other exercise bikes with a magnetic resistance system, the Sunny SF-RB4616 features a belt drive system. The internal belt is quite durable and delivers smooth, silent operation. Also, as opposed to a chain drive, it does not require any lubrication.

Sunny SF-RB4616 Recumbent Bike

The weight of the internal flywheel is not specified. But considering that the bike’s weight is only 59 lbs (27 kg), the wheel should weigh somewhat between 8-12 lbs (3.6 – 5.4 kg). It’s a balanced flywheel that promotes a steady pedaling motion.

The bike comes equipped with a durable crankset. However, it is not a bike made for standing up on the pedals. Any workout of this sort may damage the internal components.

The pedals feature a weighted design. They should always turn face-up when you remove your feet from them. They come with adjustable straps and have a non-slip surface. Their threads are also standard, so you can easily find replacements for them if needed.


The Sunny SF-RB4616 includes a fitness console. This unit does offer a bit more than the basic units, as it has an odometer function and a pulse reading function. It has an LCD that can track time, distance, total distance (odometer), speed, calories, and pulse. It doesn’t offer user input data, such as weight, age, or gender, so the calorie reading isn’t too accurate.

The unit is not telemetric, so it can’t read your pulse via a wireless HR chest strap transmitter. To benefit from a pulse reading, you will have to use the EKG sensors within the seat handlebars.

The console unit is easy to operate. It has only one button which toggles the SCAN function On and Off, and also serves as a Power On button and as a Reset button. When the SCAN function is On, the display will show each workout metric for several seconds, then moving to the next and so on.

By toggling the SCAN function Off, you can select any of the workout metrics to be shown on display all the time. To reset all the workout metrics on the console, you simply have to press and hold the button for a few seconds.

The console is battery powered. It uses two AA-type batteries, which are (included) with the bike. It also has a sleep mode to which will enter after several seconds of inactivity on the bike. To turn it on, you can either press the button or begin pedaling.

Sunny SF-RB4616 Recumbent Bike
Sunny SF-RB4616 Recumbent Bike

SF-RB4616 Assembly & Maintenance

The main body of the bike comes pre-assembled. However, there still are parts that require assembly. You will have to attach the two base bars to the mainframe, the seat, the console mast, the handlebars, the console, and the pedals.

This may take more than an hour of your time. However, the included manual provides clear assembly instructions and schematics. Also, the tools required for the assembly are (included) with the bike.

This exercise bike features a magnetic resistance system; thus, there isn’t any maintenance required for the internal parts. The only thing to do for this matter is to check for loose bolts and parts periodically.


  • Sturdy, steel frame, capable of supporting users up to 300 lbs;
  • Transport wheels on the front base;
  • Adjustable base stabilizers on the rear base;
  • Step-through frame design for easy access to the seat;
  • Both front and seat handlebars (other recumbent bikes don’t have front handlebars);
  • Pulse sensors incorporated into the seat handlebars;
  • Padded seat and backrest, for optimal comfort;
  • Quiet magnetic resistance system;
  • Adjustable resistance offering distinctive eight levels;
  • Weighted pedals with adjustable straps;
  • Fitness console that can track time, distance, total distance, speed, calories, and pulse;
  • Lightweight, easy to handle;

    Sunny SF-RB4616 Recumbent Bike
  • Reasonably easy to assemble;
  • Little to no maintenance required.


  • No tablet holder;
  • No backlight on the exercise meter display.

Sunny SF-RB4616 Summary

The Sunny Health & Fitness SF-RB4616 is a recumbent bike made for home use. It features a manual magnetic resistance system, a belt-drive, and includes a basic fitness console. It comes equipped with a comfortable and adjustable seat. Additionally, it has a reasonably sturdy frame, rated for a maximum user capacity of 300 lbs.

It’s a great trainer for recovery training, muscle toning, and stamina development. You can also lose weight with this bike if you undergo a more intense cardio regimen, on the 7-8 resistance settings. In all, it’s an excellent and also affordable exercise bike, currently available for less than $200.

I hope you found this article helpful and informative. If you have anything that you’d like to share or any opinions about my website, please do speak up. I look forward to your comments, questions, and the sharing of ideas.

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3 thoughts on “Sunny SF-RB4616 Recumbent Bike | It’s a Reliable Bike!”

  1. Oh, with all of this quarantining, you KNOW I’m guilty of not getting enough exercise, and I know I won’t be going to a gym for a long time (high-risk group). Now is the perfect time for me to get a bike. I usually walk for exercise if I’m out and about, but I think for being at home, a bike is much more versatile than a treadmill. Also generally cheaper and always more compact. The Sunny Recumbent Bike looks like a good option for me, as I can easily afford it, and it has all of the features I need. I’m also a huge Amazon user. Thank you!

  2. Thank you so much for sharing us an interesting and excellent article. It is truly admirable that you have demonstrated this topic so well in your review. I have learned a lot by reading your article and gained a lot of cognition about Sunny SF-RB4616 Recumbent Bike. Of the points mentioned in your report, I like seat & handlebars. I think this model bike is perfect for exercising at home.

    I would like to share the subject of your article in my Facebook group so that everyone can know about exercise equipment and purchase this type of exercise equipment.


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