Retrospec Koa Rev 2 ST Review | Stable & Simple

In our Range Test, we evaluated the Koa’s minimum and maximum range by conducting two separate tests: one using its highest assist level and another using its lowest assist level, riding until the battery was completely drained.

In the bike’s maximum power setting, set to Class 2 speeds, it achieved a total of 22.28 miles. When ridden on its lowest power setting in PAS 1, it covered a distance of 40.22 miles.

These results were slightly below Retrospec’s claimed range of up to 52 miles per charge. However, the mileage aligns with our expectations based on similar fat tire bikes we’ve tested. Fat tires, a 500W motor, and a battery between 500-600Wh typically deliver a range of 25-46 miles in our testing.

Overall, the electrical system’s efficiency met my expectations. While the 500Wh battery isn’t the largest—most modern bikes now use 600-800Wh batteries—it pairs well with the 500W motor. A larger battery would increase both cost and weight, so this setup strikes a reasonable balance. Life is all about trade-offs, after all.

For most riders, a range of 22-40 miles should be sufficient for a day or two of use. If you’re looking for an extended range and are still intrigued by the Retrospec brand, consider the Koa Rev+ model. It features a larger 720Wh battery and a more efficient torque sensor engagement system, offering improved mileage.

We take each bike to our Hill Test to see how it can do on a steep and drawn-out climb. The Koa Rev 2 ST proved capable, but only if you’re willing to put in some leg effort.

In our throttle-only test, the Koa couldn’t make it to the top of the hill. Our tester, Justin, had to put a foot down midway up the climb, meaning the bike couldn’t complete that portion of the test. This isn’t unusual—a lot of 500W motors either fail to make it up or post slower times.

However, with added pedal power and the Max PAS (pedal assist) setting engaged, the Koa managed to climb the hill in one minute and 48 seconds, averaging a speed of about 10 mph on the ascent.

Overall, the Koa is capable of handling steep hills—as long as you’re prepared to pedal—but it’s not a particularly fast climber. For comparison, the average hill climb time for all e-bikes we’ve tested is about one minute and 28 seconds. Even when narrowed down to bikes with 500W motors, the results are similar, placing the Koa on the slower side of the spectrum.

While this might sound like bad news, it’s important to remember that most riders would walk a non-electric bike up this hill. So, making it to the top at all is a notable achievement. Just be ready to pedal if you encounter steep inclines like this one.

This bike is best suited for riders in areas without extreme hills. It truly shines on flat terrain, where the motor’s controlled and steady nature makes it ideal for zipping around town or cruising along the boardwalk.

The brake test was a standout for the Koa Rev 2, delivering an impressive 21-foot stopping distance.
I’m calling it impressive because it beat the averages—something I honestly didn’t expect from a mechanical brake setup.

Currently, the overall average stopping distance across all the e-bikes we test is 21’ 9”. For fat-tire bikes specifically, the average is slightly longer at 22’ 6”. So, no matter how you look at it, the Koa’s performance is exceptional.

I believe much of this performance is due to the bike’s weight. The Koa is one of the few 26×4” fat-tire bikes that weighs under 70 pounds, and that definitely worked in its favor during this test.

The mechanical brakes also deserve credit. They performed admirably and offer the added benefit of being less expensive to maintain or repair over the bike’s lifespan.

There are many practical elements to the Koa Rev 2 ST that I appreciate, starting with comfort.

The low step-over height, combined with the wide fat tires, makes it easy to hop on and maintain balance. The suspension fork, while not as stiff as I’d like for my 230-pound frame, effectively absorbs road imperfections, resulting in a fairly comfortable ride overall.

The handlebar is on the narrow side, but when paired with the wider tires, it creates livelier handling without feeling twitchy. I like how the two elements combine.

Class 2 speeds feel very predictable. The bike’s motor engages nearly instantly but at a manageable pace. Acceleration builds steadily, effortlessly propelling you to 20 mph at full speed, and will linger for up to a second after you stop pedaling.

Class 3 performance, on the other hand, is quicker and punchier. It almost felt like a different bike, which, as a speed-oriented rider, I really enjoyed.

The bike has a nice, minimal appearance (with quirky “I’m Turned On” lettering over the seat stays) and practical features like included fenders and lighting. I like that the taillight doubles as a brake light—more communication on the road is always a plus.

As I mentioned in the introduction, this bike feels like a bare-bones essential. Many of its parts are tried-and-true but entry-level, which I actually like. This simplicity makes it an excellent option for riders looking for a stable bike without paying extra for features they may not need—like advanced gearing or a massive battery for all-day treks. Keep it simple, keep it fun.

The internet thrives on buzzwords—both in the marketing and advertising of products and often in their reviews as well. Everyone is trying to grab your attention with a catchy title (I do this, too; it’s a necessity these days). So, I realize that calling a bike “Stable & Simple” up in the title might not sound like the most exciting endorsement, but it’s a sincere one for a bike that I genuinely liked.

Many fat tire e-bikes try to be everything at once: a powerhouse super-commuter, an off-roader, and a jack-of-all-trades for activities most people will never actually do. This bike is different. It focuses on the basics, keeps costs relatively low, and delivers on the fundamentals of a fun, safe, and secure ride. Its confidence-inspiring design makes it an excellent choice for many riders.

If you want more power, more range, or more features, good news: there’s the Plus model for that. But if you’re simply looking for a bike that will get you outside more often and feel stable beneath you, this one is definitely worth considering.

Happy Riding! Make sure to let us know if you have any questions or if you think we left anything out in this review of the Retrospec Koa Rev 2 ST down in our comments section.