Manufacture: Fifield

Model: Jetty 4.0

Type: Folding E-Bike

Price: $1399



  • A Fifield Best-Seller!
  • Lightweight Superiority
  • GLOW IN THE DARK FRAME – And Tires Too!
  • Strong 350W Motor
  • Samsung 36V 10.4 Ah Lithium Battery
  • Smart Power-Assist Settings
  • Mechanical Tekro Disc Brakes
  • Backed by a 2 Year Warranty!
  • Specs
  • Conclusion



⚡ Affiliate Disclosure ⚡

As the Owner of Radical Electric Bikes, I enjoy finding the best deals on E-bikes and Gear to review providing accurate and unbiased information to you, the visitor and my welcomed guest. I use affiliate links on most of my posts and videos. When you decide to buy a product after clicking on one of these links, I get paid a small commission and you get a great deal on a new Ebike, Scooter, accessories & other great gear. It’s a win-win! Full Affiliate disclosure can be read here.




A Fifield Best-Seller!

Already into its 3rd generation, the Fifield Jetty 4.0 is a top-notch folding bike that has proven Fifield’s quality and performance in all areas. The Jetty 4.0 packs many features for safety, power assist settings, and last but not least – glow in the dark frame! Backing you up in the dark further with front and rear lights, the Jetty has it all! Let’s take a closer look at all the specs and more details of Fifield’s Jetty 4.0 below.


Lightweight Superiority

First and most noticeable feature is the lightweight of only 40lbs. Especially for a 350W being a bit larger, the weight is still lower than most folders in the Jetty 4.0’s class. You can pack the Jetty anywhere you go in the car, securely keep it in your apartment, or any other tight space that the Jetty can slide into. In 10 seconds or less, you will have your bike folded back out into position to ride away wherever you please! Also included rear rack lets you take your groceries or lunch out for the day.

Lately Fold up types have been catching my eye for my soon to happen trip back to Thailand and abroad since it’s so light and transportable. I will follow up with an article in the future regarding how this works because many people want to know about battery legalities overseas and all that jazz. This article will be updated with a link to that new article when it is available as soon as possible.



My favorite safety feature of the Jetty 4.0 is the glow in the dark frame. WHAT? That’s right! You and your sweet ass will be visible 100% in all directions for other road users and pedestrians at night and through tunnels that obstruct sunlight. This is a cool feature that may be seen as “Shiny” to thieves and no-do-gooders so I personally would take this bike with me inside and out everywhere I go.

A plus to the Jetty 4.0 is the included Front and Rear LED light, this compliments the bike in a way that makes it look like something from a sci-fi novel or movie. Asides from cool looks, your visibility is also increased for 360 degree coverage shining a reliable illuminated presence on the road. That’s not all, the Kenda tires are also reflective and grip the road confidently. What more could be done to this bike, besides mounting an aircraft light onto it?

For even better safety and visibility at night, wear a reflective vest that is lightweight and doesn’t over encumber you. Check out my helpful article on Lights and Reflectors here for more safety tips and how to best utilize your lights for maximum effectiveness during the night.


Strong 350W Motor

Most folding bikes use a 250 Watt Motor to compensate for weight and bulkiness. Your Jetty 4.0 here packs a more powerful yet just as compact 350 Watt Rear Hub Motor which will throw you surprisingly up the road to a top speed of 20 miles or 32 kilometers per hour! This is the speed limit for E- bikes here in British Columbia, so you can rock all the power of a regular size E-Bike with all the transportable features of a folding type. In the States and other countries, your speed may be higher!


Jetty 4.0

The Jetty 4.0 in red.


Samsung 36V 10.4 Ah Lithium Battery

The power plant for the 350W Motor is a Samsung 36V 10.4Ah Battery. This type will give the rider a maximum range with assist up to 30 – 45 miles or 48 – 72 kilometers. That’s the regular range you would be getting with a regular E-bike like the Fifield Seaside! When using the throttle on the Jetty, this range will be affected depending on the amount of time the throttle is used, rider weight, wind, etc.

For smooth derailleur operation and optimal performance is the Shimano Tourney SIS 8-Speed Gears. It has the shifter on the right side as usual and is a twist operated type. Use your wrist to adjust to the level you want on the hills and flats.


Smart Power-Assist Settings

Fifield’s Jetty 4.0 is mounted with a BM5S King Meter LCD Display that tunes your assist setting to 3 different levels – low, medium and high. It also will display you speed, remaining range / charge, and operates the rear and front light. This can be later set up with an optional USB charge port.

Another note about the motor is it’s incredibly silent operation. E-Bikes are quiet already, whereas the Jetty 4.0 Is almost unidentifiable as an E-Bike compared to a regular folding bicycle. The only difference is how you hilarious you will look when flying up a hill on such a small bike! And always wear a helmet, the torque can be surprising for some people and catch you off-guard!


Mechanical Tektro Disc Brakes

For reliable stopping and maneuverability, the Jetty 4.0 is equipped with Mechanical Tektro Disc Brakes that take on all weather and temperatures. Being in its 3rd generation, the Jetty also set up with internal gearing for protection from the occasional fall or mishap when a friend is trying it for example.

Folded in half for storage and transportation.


Backed by a 2 Year Warranty!

With a history of reliability and proven quality, the only thing that could make the Jetty 4.0 even a better deal is the 2 Year Warranty. Fifield got it right in the first gen, I love seeing companies that outdo themselves in terms of customer approach ability regarding price and warranty.



  • 350W Rear-Drive Brushless Motor
  • Samsung 36V/10.4 Ah Lithium
  • KM5S LCD King Meter Display
  • 3 Level PAS System and Throttle
  • Max Speed of 20 miles or 32 kilometers per hour
  • Max Range of 30 – 45 miles or 48 – 72 kilometers.
  • Front and Rear LED Lights
  • Aluminum Alloy Frame
  • Aluminum Handlebars with folding stem
  • Wheels: 20″ magnesium alloy
  • Weights 40 lbs
  • Shimano Tourney SIS 8-Speed External Gears
  • Kenda Reflective Tires with Kevlar belt
  • Tektro Mechanical Disk Brakes
  • Front and Rear Fenders with Bell
  • 2 year Warranty for Frame, Battery & Motor
  • Sizes: One Size
  • Available Colors: Red or Blue



Fifield didn’t miss a beat on this one – the Jetty 4.0 outclasses most of its competitors for the amazing attention to details regarding not just its safety features, but also in terms of power to weight ratio and the incredible range you get out of the juicy Samsung Lithium Battery! Kudos to Fifield for such care and the improvements made to each generation making it even better than the last.

The Jetty gets a Radical rating of 100/100, this is the most loaded fold up bike I have ever seen! The only thing that one would maybe consider as “missing” since it’s so packed is a USB charge port (An optional feature which would have been nice, but oh well). Still, worthy of the 100/100 rating nonetheless.

Are you a fan of fold up bikes or are looking for one? Look no further, the Jetty 4.0 is highly recommended to anyone that wants to buy their first one or add to their collection. Leave a comment below if you have a question, or would like to share your experience owning the Jetty 4.0 with other readers looking for a trusty fold up E-Bike 🙂 Complete Pros, Cons and more observations can be found at the bottom of this review.

Fifield Jetty 4.0


Build Quality


Safety Options


Extras & Accessory Compatibility



  • Glow in the dark Frame
  • Front & Rear Lights
  • Throttle + Regular PAS System


  • Spaced Spokes instead of regular ones (Can't be easily fixed if damaged).
  • Costs the same amount as some higher end folding E-Bikes.
  • No USB charging port for mobile devices.

Share this information with your friends and family!

Rowan McLeod

Rowan founded Radical Electric Bikes in January of 2019 to guide fellow E-Bike riders, Scooter & Motorcycle enthusiasts.

Check his online store! Send questions & requests to ⚡


  1. Reply

    I enjoyed reading this review. The Fifield Jetty looks like a cool bike to have. While I was reading your post, I felt like wanting to try it out.

    This bike is certainly something I’d want at some point. I loved riding bikes as a child- it was one of my favorite hobbies. I wish this kind of bike was around while I was growing up- boy it would have been an awesome experience!

    Maybe not now, but someday I’ll purchase this bike. I’m definitely bookmarking this page to come back to.

    An excellent review- thanks for sharing!

    • Reply

      Same with me! Having these as a kid would have been a blast! A whole new reason for training wheels – just a shout out to you parents reading this!

      The Jetty 4.0 goes above and beyond what I expected from a folding electric bike. Here is a direct link to purchase the Jetty 4.0 here for your bookmark 🙂

      – Rowan @ Radical Electric Bikes

  2. Cherise


    I’m in the market for an electric bike, I have been researching for awhile and I like what I see with the Fifield Jetty. The glow in the dark feature is beyond awesome. Thanks for the info

    • Reply

      I love the glow in the dark feature too, it’s brilliant!

      I recommend the Jetty to anyone looking for a transportable and lightweight electric bike. There are links to buy the Jetty in the review, or click here now to purchase your’s today!

      Rowan @ Radical Electric Bikes

  3. Reply

    What a beautiful electric bike! My husband cycles to work and in the winter complains about his lack of visibility to other cars. I love that this model has a glow in the dark frame and tires. What a great concept! This looks like the perfect bike for him. I want to try it, too, especially on the hills by us. Thanks for the helpful review.

    • Reply

      It’s such an important feature for the night, especially if an ebike is your primary mode of transport. See and bee seen!

      – Rowan @ Radical Electric Bikes

  4. Andrea


    I have a fold-up bike myself and I’m looking for an upgrade for the summer this year! Fold-up bikes are great to begin with due to the portability and all, and this one has some very attractive features! Thanks for the review!

  5. James Stockwell


    I have purchased the Jetti 4.0 and it’s great! On your website under cons it says that it doesn’t have a usb charging port for your phone, but the fact is that it does have one next to the ebike battery charging port. I just wanted to let you know. Thanks

    • Reply

      Looks like I overlooked the USB port indeed, I appreciate you pointing this out James, have an awesome day!

      – Rowan @ Radical Electric Bikes

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