Sunny Health & Fitness SF-RW5713

The Sunny SF-RW5713, also referred to as the Obsidian Surge Power Rower is a top-quality water rower from Sunny Health and Fitness. It has become a top seller on Amazon due to its high level functionality and affordable price. 

Sunny Health & Fitness SF-RW5713

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Rowing machines, in general, are experiencing a massive surge in popularity. People are just realizing how effective they are at burning fat and building lean muscle. They are now marketed as able to help you put on muscle like a sailor.

In the ancient days, sailors were greatly feared, not only for their ‘fishy’ odor and terrible dispositions but also for their substantial muscled frames.

Nowadays, many manufacturers have come up to satisfy the growing demand, and few are as illustrious as Sunny Health and Fitness. This review of its Obsidian Surge Power water rower proves that the company still makes quality exercise equipment.

General Features and Technical Specifications

  • Item size – 80″L x 22″W x 34″H
  • Item weight – 91.9 lbs (41.7 kg)
  • Folded size – 22″ x 33″
  • Seat height – 17″
  • Maximum weight capacity – 300 lbs
  • Resistance type – Variable water resistance.
  • Console – 5.5″ display with buttons for control.
  • Warranty – 3 years.
  • Storage – Can be raised to rest on its front; has transport wheels.
  • Pulse monitoring – Wireless chest strap, sold separately.

Sunny Health & Fitness SF-RW5713 in More Detail

The Sunny SF-RW5713 follows the same basic design as most of the water rowers on the machine. It has the main body with the water tank mounted horizontally, and the monorail extending behind it.

The frame is made of industrial-grade tubular steel. It is a bit on the lighter side though and can support a maximum of 250 lbs in user weight. Some models are made of thicker material and have a higher threshold. If you’re a hefty guy, you should look elsewhere instead .

Apart from that, this water rower is superbly built. The joints are precision welded together to ensure maximum strength, and it has been finished to a high-quality standard. 

The monorail is made of solid aluminum in an I-bar shape. The seat rolls over it, so it has to be exceptionally smooth. It is milled and ground to perfection and then covered with a light layer of lubricant.

Aluminum is naturally resistant to corrosion, and the rest of the steel parts are painted with a tough coat of black powder paint for the same reason. 

Due to the high quality of this machine, Sunny gives a 3-year warranty. During this time, any significant issues that do not result directly from the user will be sorted out free of charge. 

Resistance, Water Tank, and Paddles

Being a water rower, the Sunny Obsidian Surge derives its resistance from paddles rotating within a water tank. It is the same principle used by boats but on a much smaller scale. As the paddles move through water, they encounter resistance which you have to work against.

To maximize efficiency, Sunny used genuine, high-density hydro blades. These maximize drag and hence resistance while giving you a fluid motion every time. Even more important, the blades are designed and built to resist corrosion as well as wear. They can endure the vigorous churning for ages, which makes it almost maintenance-free.

The water tank is made of translucent polycarbonate material and has six markings for different water levels. Each level represents a specific resistance, so that you can vary it by emptying or filling the tank. There is a small pump included with the unit for that purpose.

Other than that, since this is a water rower, the resistance is variable. To adjust the levels, you don’t have to use the pump. Instead, you can increase or decrease the speed. The faster the blades spin, the more the resistance. The slower they are, the less it becomes. This is a neat feature because it makes high-intensity rowing at intervals (HIIT) without having to pause for adjustments.

Seat, Monorail and Footplates

The seat is designed for maximum comfort and utility. It is ergonomically shaped with a contoured surface. The contouring helps it to grip your body better and to prevent sliding as you row. 

It is also covered in foam cushioning for two purposes: it makes seating comfortable even for prolonged periods and is soft to give a good grip on the seat. It is placed at 17″ high above the ground, which makes it comfortable to on and off. 

Sunny Health & Fitness SF-RW5713

Since it rests on three sets of metallic ball-bearings, the seat is able to move smoothly and noiselessly on the monorail. The bearings are found on the inside seat to prevent injury and are big enough to distribute weight evenly.

As for the footrests, they are designed for comfort, stability, and durability. Since they anchor your feet not only during the drive but also during the recovery, they need to withstand a lot of force. The Sunny SF-RW5713 has metal plates for the footplates due to this.

The footplates have then been covered with industrial plastic for comfort. The surface of the footrests is slightly oversized to fit all people, but it can be adjusted as necessary. It also has thick Velcro straps to hold your feet securely as your train.

Also, the footrests are not fixed in place. Rather, they articulate slightly so that your feet are always in the most natural position. It helps to prevent strain to the ankles and calves and makes it easy for both short and long-legged users.

Console and Pulse Monitoring

The Sunny Obsidian Surge has a nice display mounted on its console. Unlike many other models, this one is a large 5.5″ dot matrix display that is divided into several parts. There are sections to display your heart rate, time spent, the program running, number of strokes, distance, etc.

However, the console is unlit and can only be used in a room with enough lighting. Apart from that, it is powered by a pair of AA batteries and thus requires no mains connection. The machine also comes with a pair to get you going.

There are two modes on the console which are designed to motivate you better to reach your goals. One of them is the manual mode where you just start rowing, and it displays your performance. A second manual mode allows you to set a personal target as per pulse rate, distance, number of strokes, or time spent.

The other one is Race Mode. Fifteen levels of these are available, each with its difficulty level. Each level gives you a specific pulse rate, time, and distance to cover. You have to race against the machine to achieve the target.

Besides, the console gives you two other options. You can calculate your fitness level by taking a short test, or you can test your recovery levels, whereby it calculates the time taken for your pulse rate to get back to normal after intense exercise.

The machine lacks an inbuilt pulse monitoring system. Instead, it has telemetric capabilities that allow it to connect with a chest strap (such as Polar) to monitor your pulse rate. You can get a strap delivered with the machine, but you would need to purchase it separately.

Assembly and Maintenance

The machine is delivered in two major parts. Most of it is already pre-assembled, such as the water tank and supporting frame. 

The parts that need assembly include the monorail, seat, stabilizers, and the console. These are all very easy to assemble, and all the tools and parts necessary come with the package.

Maintenance is also easy and straightforward. Every two weeks, or at most every month, you should clean the machine with a wet cloth. Pay special attention to dust, grime, or other foreign material on the monorail and under the seat. Apply a light coat of lubricating oil with a cloth.

Every six months or so, you should add a water purification chlorine tablet in the water tank. It helps prevent the growth of algae in the tank.


  • Very stylish and classy look.
  • Durable, with a 3-year warranty.
  • A nice console is present, which displays all the workout data you need without having to cycle using buttons.
  • The seat is high at 17″, making it easy to get on and off.
  • It can be stored vertically to reduce space requirements. It also has wheels for easy transport.


  • The weight capacity of 250 lbs is a bit low. Hefty users will have to look to other models.
  • The chest strap has to be purchased separately.
Sunny Health & Fitness Obsidian...
  • WATER PERFORMANCE: Instant resistance is available with the flywheel and 16 fan blades. The faster the fan blades spin the higher resistance and dynamic response caused by the harmonious interaction with the water, giving the user a unique experience.
  • DESIGN: Constructed with lightweight sturdy steel, for solid performance and durability. The 16 hydro-blades mimic the dynamic movements of competitive rowing along with sweat resistant handlebars.
  • ERGO EFFICIENT: Molded padded seat is designed to be comfortable and functional. High-profile seat design allows user to get on and off the seat without bending and straining your back.
  • FITNESS TECHNOLOGY: The R2 fitness meter is designed to accurately track all essential workout metrics, i.e. total time, 500 M time, SPM, total strokes, calories, hr., ambient temperature, and more
  • EASY STORAGE: High density non-marking rubber wheels are perfect for easy transporting. The rower can be stored upright when not in Use. Recommended to be placed upright against the wall for storage.

Last update on 2022-07-04 / Affiliate links / Images from Amazon Product Advertising API


The Sunny Obsidian Surge SF-RW5713 is a great mid-range option when you want a functional water rowing machine at an affordable price. While it is true that there are cheaper versions, the Obsidian Surge outclasses them and is also of overall better quality.

This rower will give you a challenging workout, whether you’re a beginner or expert athlete. The option to have HIIT training due to its variable resistance is a fantastic option for those who are serious about their fitness. 

For the price at which it is offered, the Obsidian Surge from Sunny is a sweet deal. If you’re convinced, get it here from Amazon.

About Gaurav Dhir

Gaurav Dhir, B. Tech, PGDCM is an engineer and MBA by training. A fitness aficionado, Gaurav follows a strict diet and exercise regimen to keep himself vigorously active. He loves playing sports and being outdoors. Gaurav is responsible for the health and wellness of 4 generations including his son, elderly parents and very elderly grandparents.