Sunny Health and Fitness SF-RB4850 Review: A good recumbent bike?

Recumbent stationary bikes can be some of the more expensive pieces of exercise equipment due to their differences from more traditional upright bikes. Due to this increase in price, it can turn many people away from looking at them. However, there are those that seek to fix this issue by making their models much cheaper than the average recumbent exercise bikes.

The most notable of these has to be the Sunny Health & Fitness SF-RB4850 recumbent bike. This is one of the cheapest recumbent exercise bikes you can find. But you don’t always want a model that is just the cheapest. You want quality as well. That’s what we’re going to be looking at today.

How well does the Sunny Health and Fitness SF-RB4850 recumbent perform in regards to its technology, resistance, and comfort? Once we look at all these elements, we’ll give our opinion on the overall value of the exercise bike and speak about potential better alternative options. So with all of that out of the way, let’s get our review of the Sunny Health & Fitness SF-RB4850 recumbent bike underway!

Price, Warranty, Shipping, and Assembly

We’ve mentioned price multiple times now, so it seems to only make sense that we start with that. You can find the SF-RB4850 recumbent bike for a price of around $400, give or take about $30. This is quite cheap for one of these bikes, which is obviously ideal. Nobody wants to be dropping thousands of dollars on the bikes unnecessarily.

You also want guarantees that you can get replacement parts in the unfortunate case that something breaks on the SF-RB4850. Knowing Sunny Health & Fitness (SH&F), they attach the same warranty package to everything. You get 3 years on the frame of the bike and 180 days on the parts. This rarely changes for SH&F and mostly serves as a decent basis.

The more expensive the machine, the worse it is. At least in comparison to many other warranty packages in the recumbent exercise bike realm, it really is pretty bad. But we could complain about the warranty all day, so let’s move on.

The shipping process of the bike should take only a week or two before it arrives, although this can be affected by your location, human error and more factors. Once it does arrive, you shouldn’t have too tough of a time putting it together. SH&F bikes tend to have instructions that are clear and easy to follow along with, even for those who aren’t particularly skilled or experienced with them.


One of the most important elements to modern bikes (and exercise equipment in general) are the electronics attached. The SF-RB4850 recumbent bike is no different in this respect. However, because it is one of the cheaper bikes, don’t expect a revolutionary experience in this regard.

It has a console that divides into several sections that displays all of its statistics on a backlit LCD screen. These stats include the time, distance, total distance, calories, watts, speed, RPM and pulse. You don’t get to track heart rate through chest straps, so only estimations via the handlebars.

As for the preset programs and activities that you can access on this monitor, there are a total of 24 including the manual mode. There are modes that implement hills, those that try to achieve a certain heart rate, a body fat program, and 4 programs that allow for the user to set up their own custom routine.

It’s actually not a bad package, but there are still a couple weaknesses. The major one being that there is no sort of Bluetooth connectivity or online options available. Considering how many consoles do have connections with some sort of apps these days, it is a big miss. You’ll also notice that half of the console is just a sticker that shows the heart rate zone you should be looking for based on your age. This feels like a little bit of a waste of space, as it seems like there could be more useful things in this spot. It certainly is nothing compared to monitors you’d find on the Nautilus R616 and Schwinn 230.

Resistance levels and flywheel weight

Up next is another crucial part of stationary exercise bikes; the resistance. Considering this determines how well you can use the bike to get fit, it seems natural to want it to be built well. The resistance system of the SF-RB4850 recumbent bike is an automatic magnetic one, meaning that it will require to be plugged into an outlet in order to change resistance levels.

It has a belt drive that combines nicely with this magnetic system in order to make workouts nice and quiet, not to mention smoother than a chain drive would make it. However, there are common complaints of this belt breaking quite quickly, which is concerning.

There are 16 different resistance levels available here, with the upper levels providing a stiff challenge. While this isn’t the highest amount of resistance levels that you’ll ever find, it should still allow for some customization and refinement of workout levels.

Q-factor, pedals, and crank system

One of the bigger weaknesses of the SF-RB4850 is that it has a 1-piece crank. These are always inferior to the 3-piece cranks, as they are little more than a single welded bar holding the pedals together.

Another potential weakness is the light flywheel, as it only weighs 6.6 lbs (3 kg). Some people don’t like these lighter flywheels, but this one still does a pretty decent job. We don’t know the Q-Factor of the SF-RB4850. This is the distance between the pedals. If it is too wide or too narrow, you can get uncomfortable or even risk injury.

Dimenssions and weight

Many people like to know how large of a piece of equipment they are getting, especially those in smaller homes. While the bike isn’t particularly huge, it is made of a pretty heavy steel frame. Specifically, the SF-RB4850 recumbent bike measures out to be 59 inches (150 cm) long, 26 inches (66 cm) wide and 47.5 inches (121 cm) tall.

Meanwhile, it weighs a solid 87 lbs (39.4 kg) and can hold a maximum weight of 300 lbs (136 kg). There are transport wheels on the front of the bike, allowing for easier movement around the home. There are some stabilizers on the rear of the bike, but they aren’t all that great. However, you shouldn’t find that rocking around is too big of an issue on the SF-RB4850.

Hand-grips, seats, and backrest

We’re going to finish out with the rest of the physical elements of the SF-RB4850 recumbent bike, starting with the handlebars. There are 2 pairs of handlebars here, with 1 besides the seat and 1 coming out of the console. Both are covered with a rubber coating for comfort, while the ones next to the seat have pulse sensors in them in order to provide that estimation of your heart rate. However, that’s about all they do and neither of them are adjustable.

The general setup is similar to other bikes like the Circut Fitness AMZ-587R and Schwinn 230 bikes, but it lacks some of that extra polish. The seat, on the other hand, is adjustable about 10 inches. This generally means that it can fit people between 5’2” (157 cm) and 6’5” (196 cm).

The back of the seat is made of a mesh material in order to allow for some breathability, while the seat itself is quite wide and heavily padded. Surprisingly, there don’t appear to be too many complaints about the comfort of this seat, which SH&F have had problems with in the past.

The pedals are nothing special. They are self-leveling with adjustable straps, but that’s the standard for these bikes. As for any additional features on the SF-RB4850 recumbent bike, you get a tablet holder on the main console and a water bottle holder under the console. But no cooling fans or USB chargers or anything like that.

Sunny Health and Fitness SF-RB4850 Recumbent Pros:

  • Magnetic resistance system combines with belt drive for a smooth and quiet system
  • 16 different resistance levels is a good amount
  • 24 different prest workout programs allows for a wide variety of workouts
  • Console allows for tracking of a good variety of workout statistics
  • Bonus tablet holder and water bottle holder
  • Heavily padded seat is actually pretty comfortable, adjustable and has a mesh back
  • Sturdy frame with 300 lb weight limit
  • Transport wheels allow for easy transportation around the home
  • Extremely cheap price compared to other recumbent bikes

Sunny Health and Fitness SF-RB4850 Recumbent Cons:

  • Common complaints of the belt drive breaking quickly
  • 1-piece cranks are always inferior
  • No online connectivity or Bluetooth is available here
  • No additional bonus features like USB plugs, speakers or cooling fans
  • Poor warranty package that is put on every SH&F

Sunny Health Fitness Recumbent Bike Comparison

Sunny Health and Fitness has four popular recumbent exercise bikes. Each one of these Sunny exercise bikes is a little different from the other and offers a different indoor workout.

For instance, the Sunny Fitness SF-RB4850 is a traditional recumbent exercise bike that only focuses on the legs. It’s good if you want to get a lower body workout or just burn calories but not ideal if you want to build upper body muscles.

The next one is the Sunny Fitness SF-RB4631 which is more of an arm and leg recumbent exercise bike. It allows you to focus both on your arms and legs. It’s not for intense exercise or to build muscles but it’s a great exercise bike for rehabilitation and those recovering from shoulder injuries.

Then there is the Sunny Fitness SF-RBD4703 which is a desk exercise bike and has a tray that can accommodate a laptop. So, you can watch your movie or even work while setting on your recumbent exercise bike.

Lastly, there is the Sunny Fitness SF-RB4708 which is completely different compared to other recumbent exercise bikes by Sunny Health and Fitness. It is a set of moving handlebars, plus, pedals to give a full body workout. It’s the combination of a recumbent bike and an elliptical machine which is pretty popular these days. You can use it for building back, shoulder, arm, and leg muscles. It burns more calories than other Sunny recumbent exercise bikes.

One thing all Sunny Health and Fitness recumbent exercise bikes have in common is the affordable price. They are less expensive than most competitors on the market. That said, Sunny Health is really poor in terms of technology and electronics. All their fitness pieces of equipment come with basic outdated screens.

Last update was on: July 21, 2024 8:37 pm

My Final Verdict and Alternatives to Consider

Let’s be real; you’re only really going to be looking at the Sunny Health & Fitness SF-RB4850 recumbent bike if you are looking for a cheaper piece of equipment. That’s perfectly acceptable, and you will find one of those here.

It is actually a decent recumbent exercise bike thanks to the good monitor and resistance, but it does have some weaknesses. The biggest concern is the combination of complaints about the belt breaking and the short warranty package.

You don’t want your bike breaking a month after you buy it, even if it was cheaper than an alternative. It might be worth investing $100 more in this purchase and looking at the Schwinn 230 or Nautilus R616 models, as they have better warranties and more features overall.

You could also opt for Circuit Fitness recumbent exercise bike as an alternative to Sunny Health and Fitness recumbent machine. It has several better features including a nice tablet holder, a three-piece crank system, better design, and overall better quality.


Hi there, I'm Sayed Hamed Hosseiny, the founder and one of the authors at (YEB). I am a former indoor cycling instructor and personal trainer with nearly 20 years of experience. With a passion for indoor cycling, I have spent years designing cycling parts, repairing, and importing exercise bikes. All the articles, tips, guides, reviews, and comparisons on (YEB) reflect my personal opinion and expertise in the field. I'm excited to share my knowledge with fellow exercise bike enthusiasts and help people find reliable indoor cycling information and the best exercise bike for their needs. If you have any questions or suggestion, you can contact me at

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