Tern GSD (S10) Review | A Legitimate Car Replacement?

The GSD S10’s 545Wh battery is on the smaller side — the third smallest we’ve tested in the cargo category — but it’s well-matched to its 250W Bosch mid-drive motor. This is a bike that works with you, not for you, so your pedaling effort goes a long way in stretching range. Go light on assist and keep the terrain mellow, and it’ll stretch like taffy.

In our standardized range tests, the GSD covered 39.6 miles in its highest assist mode (Cargo) and an impressive 73.3 miles in Eco. That’s solid performance for this class, though it’s worth noting our tests were done without additional cargo. You should expect reduced mileage when loaded.

Compared to other bikes in our Cargo category, the GSD outperformed the average range of 34.8–70.6 miles in our database, despite its modest battery size. It’s another reminder of how efficient Bosch’s mid-drive systems can be when paired with a well-tuned drivetrain.

If maximum range is your goal, the GSD lineup offers excellent flexibility. Every model can accommodate a dual-battery setup, effectively doubling total capacity. The base trim can jump from 500Wh to 1,000Wh, our S10 from 545Wh to 1,090Wh, and the top-tier R14 can reach a whopping 1,600Wh. The S10 can even upgrade to the 800Wh packs used by higher trims for the same result (1,600Wh).

For riders regularly hauling heavy loads, running dual batteries makes perfect sense, not just for range, but for utility. The GSD S10 includes a 12W power port that can charge external devices, so doubling up on batteries can keep accessories like lights, phones, or even a heated passenger blanket powered up for the long haul. After all, if you’ve got a plug onboard, why not use it?

I’ve said it before and I’ll say it again: few bike styles benefit more from a motor than a cargo bike, and the GSD proves that point perfectly. With Bosch’s 85Nm Cargo Line motor on board, this thing makes hill climbing feel surprisingly manageable, even when loaded down.

On our test hill, the GSD reached the top in 2 minutes and 19 seconds, averaging 13 mph. That’s a solid showing for a heavier, long-tail frame tackling such a steep grade. For context, our all-bike average currently sits at 2:06, while cargo e-bikes typically clock in closer to 1:53. Many of those faster times come from bikes using higher-powered hub motors, so while the GSD isn’t the quickest, it stands out for how controlled and composed it feels under pressure.

The Bosch Cargo Line motor delivers torque intelligently, applying power smoothly and precisely when needed. Even when fully loaded, climbs feel steady and deliberate. You might breathe a little heavier, but you’ll still crest the hill without standing out of the saddle.

On the steepest sections, you’ll need to shift into a low gear and put in some effort, but the GSD never feels like it’s straining. Instead, it maintains balance and traction beautifully, giving you the sense that it’s working with you every pedal stroke of the way.

And a final shoutout for the Bosch system: it’ll inform you of how to shift. If it senses you’re in the wrong gear, it’ll advise you to shift up or down depending on the need. So it’ll take the guesswork out of it for you making sure you’re riding as efficiently uphill as possible.

Spec-wise, Tern made an excellent call here. The GSD S10 is equipped with Magura 4-piston hydraulic brakes paired with 203mm rotors, some of the most proven and powerful stoppers in our entire database. But because Tern likes to go above and beyond (and I mean that as a compliment), they didn’t stop there, they added tech, too.

The bike includes an anti-lock braking system (ABS), something still rare in the e-bike world, and especially impressive to see on a cargo platform. The goal is enhanced control: if you need to grab a handful of brake in an emergency, ABS helps prevent wheel lock-up so you can still steer away from danger instead of skidding straight into it.

In our standardized brake test, the GSD stopped in 21 feet, 10 inches, which is slightly better than our all-bike average of 22 feet. It’s about a foot longer than our cargo bike average, but that’s easy to justify considering the GSD’s extra weight and its suspension fork, which can marginally extend stopping distances.

Even so, this setup inspires confidence. It performs well in both dry and wet conditions and offers precise, feathered braking when loaded down or descending with cargo. It’s also well-suited for those real-world surprises, like slamming on the brakes when a car door swings open into your lane. Once again, the Bosch display will give you data here too so you can measure youre stopping distance and conduct a brake test of your own.

Adding to its safety credentials, the rear brake light is smartly positioned under the rack, where it remains visible even when carrying passengers or gear. It’s another thoughtful touch in a bike packed with them.

The comfort, handling, extras, and—let’s be honest—the overall vibe of the GSD are all strong positives. This bike feels premium not just because of its parts, but because of how meticulously everything comes together on the road.

The frame is outstanding. The GSD’s unique design works on multiple levels, offering stiffness and stability far beyond what you’d expect even under heavy loads. With a 463-lb payload capacity, that rigidity matters. Tern also extended the rear rack compared to previous generations, giving passengers more space and comfort while expanding cargo potential. The cockpit feels a little compressed, but not uncomfortable.

Steering and handling feel great thanks to the 20” wheels, which lower the center of gravity and make the bike easy to balanc, even when it’s fully loaded. The handlebar setup is excellent too: the grips are comfortable, and the folding design feels solid and secure, with no hint of unwanted play. The folding handlebar feature also makes it easier to load the GSD into SUVs or vans, or to stand it vertically for storage using the built-in feet on the rear rack.

The fit adjustments are among the best I’ve seen on a cargo bike. Tern’s proprietary stem allows for quick, tool-free changes, which parents sharing carpool duties will especially appreciate. The reinforced telescoping seatpost has easy latch fasteners that make height adjustments simple and secure. If I have one nitpick, it’s that I’d prefer the handlebars to rise a bit higher, but at 6’1” with a longer torso, that’s a personal preference, not a dealbreaker.

Comfort components are top-notch. While I usually prefer rigid forks on cargo bikes, the SR Suntour Mobie suspension fork on the GSD provides a touch of travel that smooths out rougher roads nicely. The Cane Creek suspension seatpost is a major highlight—it soaks up impacts effectively. Add in the Ergon grips and custom Tern saddle, and you’ve got an all-day comfortable setup.

I rarely mention pedals, but it’s worth noting that I felt a bit of vibration through them when climbing hills with heavy loads. It’s minor—nothing concerning—but worth pointing out for those who notice the finer details.

Safety and security are major focal points. The GSD meets DIN frame safety standards, its electrical system is UL 2849 certified, and it includes ABS brakes, high/low beam lighting, and a bright taillight. The Bosch system also includes a free year of enhanced Flow app security ($34.99/annually after 12 months), which goes well beyond the included café lock. Through the app, you can disable the motor and battery, trigger an alarm if the bike is moved, and get motion alerts sent to your phone, all very handy features.

The Bosch Flow app adds even more functionality: GPS navigation with turn-by-turn directions (which you can send to your display), power customization, ride stats, and more. There’s a surprising amount of depth here if you like to fine-tune your experience.

Then there are the accessories—a crucial part of what makes this a true cargo bike. Foldable footboards come standard for passengers or under pannier support. Tern offers nearly endless ways to outfit the GSD. You can add simple passenger cushions, grab bars, or full guard rails, or go big with a Captain’s Chair setup. For kids, there’s room for up to two child seats, and protective canopies are available for sun or rain. There’s even a massive storage bag that can envelop passengers while leaving their heads exposed, which is a a creative (and cozy) touch.

The quality of Tern’s gear stands out: thick, durable materials, sturdy zippers, and smart design. Beneath it all, a side-rail system supports panniers and gives passengers a stable footrest. And that’s just the rear of the bike, up front, you can mount racks, bags, or even pet carriers. The built-in tow bar also lets you attach trailers without fiddling around the rear wheel. Heck, they even sell a straight tow bar if you want to start your own roadside-assistance cargo service (kidding… mostly).

So, what could be improved? Not much. The cable clutter could be tidied up a bit, and turn signals might be a nice touch someday. But honestly, those are minor quibbles. The GSD’s overall construction, versatility, and thoughtful extras make it one of the best-riding, most complete cargo bikes on the market today.

I’ve discussed cargo bikes with several CEOs, product designers, and marketing leads, and in many one of those conversations, the name Tern comes up unprompted—almost always as the benchmark. That kind of peer acknowledgment says it all: when your competitors treat you as the gold standard, you’re clearly doing something right. The GSD earns that reputation. It’s such a refined, complete cargo experience that I honestly struggled to find any meaningful faults.

The Tern GSD met—and exceeded—my already high expectations. The ride quality is exceptional: the frame shrugs off immense payloads yet remains remarkably easy to maneuver through city streets or crowded bike lanes. The Bosch Cargo Line motor deserves special praise for maintaining an uncanny consistency between riding empty and fully loaded. It senses the added weight and adjusts so naturally that, while you can tell there’s cargo aboard, the effort difference feels minimal. This is as close as you’ll get to a genuine “car replacement” experience on two wheels.

Then there are the premium details; Tern’s rethinking of everyday components in a way that makes you wonder why no one did it sooner. The proprietary handlebar and kickstand designs, the ultra-fast fit adjustments, and the abundance of thoughtful touches all contribute to a sense of daily usability and comfort that few bikes can match.

The GSD does exactly what its name promises, it helps you get stuff done, and it manages to make even the utilitarian feel luxurious. It’s not inexpensive, but if it fits your budget and lifestyle, this is one of the most capable, confidence-inspiring, and joyfully practical e-bikes on the road today.

Check it out at the link below. You might find it’s the only “vehicle” you need.

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 Tern GSD S10 down in our comments section.