Overall score
Users (0 reviews)
Our rating

Gen3 The Flex - Electric Bike Review

May 18, 2023

As of October 28th, 2022, Gen 3 Mobility, LLC has ceased operations and is no longer offering customer support. These e-bikes are not producing anymore.

When it comes to electric bikes, opinions usually go to one of the two extremes - they are either seen as inherently good or inherently bad. 

People who prefer riding “conventional” bikes don’t care much for e-bikes - while those who use e-bikes tend to swear by them and recommend them to anybody and everybody who’ll listen. 

If you ask us, both sides have some solid arguments, but that’s not what we are here to discuss. What we’d like to do, instead, is introduce you to an electric bike that might just meet everyone’s needs, whether they’re all for manual pedaling or motor-powered bikes. 

Seriously, Gen3 The Flex seems like the model to revolutionize the way people think of e-bikes. And today, we’re taking a closer look at its specs and characteristics.  

Gen3 is a relatively new name in the game, but if The Flex is anything to go by, this electric bike manufacturer might just be the next best thing on the market. Their e-bike’s design looks great on the road, they are fun but safe to ride, and they don’t seem to cut corners in terms of quality and construction, nailing the perfect balance of value and performance.  


Gen3 The Flex - Electric Bike Review

When choosing an electric bike, most people tend to get caught up in motor power, battery life, and range, thinking that these are the only features that matter. Well, today, we’ll challenge that stance and start our review with the frame. 

Think about it: 

If the frame isn’t sturdy and rugged enough, the whole concept of an electric bike goes to waste. The frame’s what holds the entire bike - and all of its components - together. 

Gen3 took note of that, constructing the frame of The Flex out of 6061 double-butted aluminum, which is nothing short of fantastic.

Aluminum is known for being light yet durable, which seems to be the winning combo for electric bikes.

The Flex weighs only 55.6 pounds, which is quite impressive - especially when you consider the maximum payload of 270 pounds. If you ever find yourself having to carry your bike up a flight of stairs or two, you’ll appreciate how lightweight The Flex is. 

We agree with Gen3’s decision to go with an aluminum frame; it will meet most people’s needs in terms of light-but-durable construction.

The fact that the overall design doesn’t scream “electric bike” is also a nice touch. Some people simply prefer the look of a traditional bike, with all the power hidden “under the hood” - or, in this case, in the bike’s frame. 

Other components that deserve mention here are the CNC Aluminum Platform Reflector pedals with Cr-Mo Sealed Ball Bearings. The wide and extra-grippy surface ensures a comfortable fit - and minimal risk of your feet slipping and losing control. 

And if this e-bike will be your daily driver, you’ll be pleased to know that the saddle doesn’t lack comfort, either. The Flex comes equipped with the Trekking Comfort Saddle with memory foam, one of the comfiest we recently had the pleasure of testing. 


Motor the flex

You know that the motor is what separates an e-bike from a “regular” one. Without the motor, an e-bike wouldn’t be an e-bike, would it? 

So, let’s see what Gen3 went with when creating The Flex.

This e-bike is fitted with a potent rear hub motor manufactured by Bafang - a well-known name and an industry leader as far as electric bike motors go - boasting 500 Watts of power, with the peak power rating clocking in at 900 Watts. 

And you really can’t go wrong with a Bafang motor

It performs surprisingly well, whether you’re using it in full throttle or pedal-assist mode. While we’re at it, The Flex features five levels of pedal assist and thumb throttle control; one push of the throttle forward, and you’ll get going without having to pedal at all.

All the while, you have a low-profile backlit display that allows you to keep track of the essential numbers - battery status, odometer, speedometer, trip meter, as well as whether the integrated headlight is on or off at the moment. 

When you’re ready to take over, the Shimano 21-speed shifter is there to back you up and make it possible to tackle those climbs with no assistance from the motor. 


The battery is one of the most important components of an e-bike, if not the most important one. It’s what dictates how long of a ride you’ll get out of your bike: 

You could have the most fantastic, insanely powerful motor out there, but if it’s paired with a less than stellar battery, you will be cheated out of the full electric biking experience, and the e-bike’s range will be cut short.

How did The Flex do in this department? 

Well, not too shabby. Okay, that’s an understatement. 

Gen3 fitted The Flex with a 500Wh 48V/10.4Ah rechargeable battery, promising a range of up to 40 miles. Of course, the total range per charge varies depending on the terrain, conditions, and the level of pedal-assist you’re using, but still, 40 miles is no joke. 

It should be more than enough for commuting to work, running errands, and getting around town - and that alone makes The Flex worth considering. 

And to make things even better - as in, safer - Gen3’s battery pack is UL-Certified, meaning it’s designed to meet strict safety protocols and the UL 2271 safety standard. 

THE FLEX battery


When riding an e-bike, the ability to stop the bike in its tracks is every bit as important as being able to travel fast. 

That part probably requires no further explanations.

GEN3 DB-330 160-millimeter front and rear mechanical disc brakes are a safe choice. Some of you might be disappointed that the bike doesn’t come with hydraulic brakes, but we can assure you that The Flex doesn’t lack stopping power. 


Tires determine whether a particular e-bike - in this case, Gen3’s The Flex - is made strictly for off-road terrains, urban environments, or a healthy mix of both. And, well, in that sense, the CST All-Terrain tires seem like a fantastic choice. 

These 26" x 1.95" tires are essentially mountain bike tires but with a road-friendly twist - the best of both worlds, as they say. 

Plus, they’re designed with Exceptional Puncture Safety (EPS) technology, promising excellent puncture resistance. 

Post-Test Summary: Gen3 The Flex Pros & Cons 

We have to admit; The Flex really lives up to its name. You’re getting all the perks of a powerful e-bike for daily commuting - but with the option to paddle unassisted and squeeze in a workout whenever you feel like it. And the all-terrain tires further contribute to that flexibility.

If you want an electric bike that can do it all, The Flex is a safe bet.

Things We Like About Gen3’s The Flex

The advantages are overwhelming compared to the downsides. We reviewed this electric bike with great attention to detail - which led us to some solid conclusions:

For starters, the Gen3’s motor is fantastic for day-to-day use. It’s compact but powerful enough to give you the boost that you need.

Moreover, the battery is decent, gives you a lot of mileage to cover - depending on which mode of pedal assistance you’re using - and takes only around six hours to charge.

Even the frame and its components are fantastic. The aluminum construction really stands out from the competition since it’s lightweight and easy to carry while retaining a durable feel. And we like the more traditional-looking design, too. 

Last but not least, Gen3 thought about comfort and safety. The saddle, the brakes, and the tires are all more than solid on this e-bike.


  • The range is up to 40 miles
  • Powerful Bafang motor
  • Five levels of pedal assist
  • Comfortable saddle paired with excellent brakes and tires
  • A strong but lightweight frame

Things We Didn’t Like About Gen3’s The Flex

If you thought we didn’t see any room for improvement on this e-bike, you’re mistaken. While we think The Flex is a fantastic choice, one thing that caught our eye is the lack of colors you could choose from here. 

It’s not a big deal, but we’d like to see The Flex in other color options besides black. 

Also, while the mechanical brakes aren’t an issue, we’re sure some of you might’ve preferred to see hydraulic ones. That’s not technically a downside, though. 


  • No options when choosing the bike’s color
  • The brakes are mechanical

Advice To Buyers

Gen3’s The Flex is the jack of all trades and can be used in countless situations - and in almost any environment.

The only problem with an e-bike such as this one is that it doesn’t overwhelmingly dominate one particular field.

Then again, who are we to judge. It’s an impressive bike - everyone who takes it for a spin will agree with us on that - and it doesn’t cost a fortune, either. 


We know that there are plenty of fantastic options out there. Rad Power, Cannondale, Trek - just to name a few. And giving a chance to a relatively new company, such as Gen3, might not come easy to some of you.

But we hope that, after reading this review, the idea of getting the Gen3 The Flex feels a bit less like a gamble - and a lot more like an informed purchase decision. 

Gen3 The Flex - Electric Bike Review
Our Rating - 89/100

We have to admit; The Flex really lives up to its name. You’re getting all the perks of a powerful e-bike for daily commuting - but with the option to paddle unassisted and squeeze in a workout whenever you feel like it. And the all-terrain tires further contribute to that flexibility.

About the author

Daria was born and raised in the Ukraine, studied in Barcelona (where she discovered her passion for e-biking), and is currently living in Barcelona. Her main passion is cycling and digital marketing, that's why she is always looking for an amazing new e-bike to make her journey even more unforgettable!

Leave a Reply

Your email address will not be published. Required fields are marked

{"email":"Email address invalid","url":"Website address invalid","required":"Required field missing"}

Want to learn more?

Check out these articles below