Stromer ST3 Pinion LE Review

This review was provided for free, but Reckless Shipyards supplied a temporary demo bike for me to test. My goal is to be transparent and unbiased with you, this video and writeup are not meant to be an endorsement of Stromer products. I welcome your corrections, additions, and feedback in the comments below, and the Stromer electric bike forums.

Observations:

• Stromer is a Swiss company that was started in Oberwangen (near Bern Switzerland) in 2009. It merged with BMC, a Swiss bicycle and cycling product manufacturer, in 2011 but eventually split off in 2016 with a new round of investment. In May of 2021 the company was acquired by a private equity firm called Nexicap Partners who are focusing on international sales in an effort to scale the company. I’ve been covering Stromer ebikes since 2013, and visited their California offices in 2016 while covering the ST2 S. They are one of the few companies that offer regenerative braking functionality and high-speed 45km/h 28mph Class 3 performance.
• The ST3 Pinion LE is one of my favorite models from the company, because I love the drivetrain and components they chose. The Pinion internally geared bottom bracket can be shifted at standstill, and is compatible with the Gates Carbon Drive belt. Excellent choice on the clamp stem vs. custom stem + handlebar used on the ST5. The bike is available in three frame sizes and three colors, with white only available for the “Comfort” mid-step frame style that’s a bit more approachable.

Pros:

• This platform is very durable. When you look at the Pinion internally geared bottom bracket and the Gates Carbon Drive belt, you can see that there’s no derailleur hanging down that could get damaged in a crash or at the bike rack. The sturdy thru-axles, thick fenders, and large Pirelli tires bring it closer to motorcycle grade than many other ebikes.
• The custom paint matched fork and battery door on the left side of the frame look beautiful and deliver a clean cohesive look. The welds on this ebike have been smoothed out perfectly and there’s a finish quality that sets it apart from most of the other electric bikes that I see and test.
• While the large battery, direct drive hub motor, thicker tires, and extra-sturdy frame do add weight, they also create inertia that dampens vibration. I am always delighted when riding Stromer products, because they feel planted and ride very smoothly.
• For those who want a bit more cushion and comfort to balance the high speeds, Stromer offers an inverted WREN air suspension fork that is amazing! I love the way it supports the same tubular aluminum alloy fender style as the rigid fork, so you’re not losing utility. Pair this with a Kinekt suspension seat post (or other 31.6mm suspension post) and the ride starts to feel even more amazing. I tested both of these options on the other ST3 during this review ride and was totally sold… even though it changes the look of the bike a bit and does add to the cost.
• The bike is just super powerful, the acceleration is above almost all other Class 3 electric bikes that I’ve tested (except for the Stromer ST5, which has a higher Sport mode). Perhaps it’s the combination of torque sensor with accelerometer and gyroscope… and the fact that it relies on a hub motor vs. a mid-drive where you’d have to switch gears to go faster. It works, and it works very well.
• Since the bike frame and wheels are so solid and stable, it feels comfortable and safe at high speeds. I think the wider 2.35″ tires with thick tread help, and they also roll smooth and quiet. The quiet motor and sturdy fenders all combine to make this feel like a luxury sports vs. rattly.
• I always appreciate being able to tap into an ebike battery to charge my smartphone or run additional lights and other portable electronics. Stromer has nailed this with their running light and rubberized USB A port that folds out. It’s fairly well positioned, and the power on offer is 4.5 amps vs. just 1 or 2 amps on most other ebike USB charge ports. This could be very useful if you add the phone mount to the top of the stem and use the Stromer smartphone app or a GPS system while riding.
• The hidden power button (positioned below the top tube) doubles as a menu button which reduces clutter on the display and control pad near the left grip. It might even deter tampering if the bike is parked outside at a public bike rack. I love that the charging port is mounted up high on the left side of the frame, and that they chose the magnetic Rosenburger plug standard that won’t crack or tip the bike if the charge cable is snagged.
• The fenders on this ebike are really incredible. They are tubular (multiple layers) aluminum alloy that won’t rust, don’t rattle, and are sturdy enough to partially support the rear rack and light, as well as work with the optional suspension fork. I jumped off of a curb and the fenders didn’t rattle at all… though I did notice some rocks would get kicked up and rattle through the fenders occasionally.
• Great touch points including locking Ergon GS1 grips, Ergon saddle, and wide aluminum alloy pedals with diamond pins. The stock setup works well for me, and I don’t feel like I’d have to change anything to enjoy the bike and feel comfortable, even at higher speeds.
• Large 203mm disc brake rotors front and rear ensure a good mechanical advantage and cooling, which is important at speed and with such weight. You get dual piston calipers on the front caliper and motorcycle style ball-end three finger brake levers for improved leverage and safety vs. a traditional two finger square end mountain bike brake lever. Both levers also activate the rear light to shine bright for added visibility.
• The stock brakes are powerful and reliable, but you can also upgrade the front to anti-lock braking (ABS) just like the ST5 ABS that I covered earlier. I found that the system actually worked and would not lock up. As someone who has crashed due to front wheel sliding out, and also gone over the handlebars on occasion, I appreciate this system more than I thought I would.
• The Pinion internally geared bottom bracket drivetrain brings weight to the center of the frame and provides a super wide 568% gear ratio (similar to what a 10 to 56 cassette would). It’s sturdy, because there’s no derailleur that could get bumped. It is compatible with the Gates Carbon Drive belt, and the frame was custom designed with a cutaway to work with this belt. The rear wheel mount is a lot stronger than a sliding droput, and they achieved this by using a 12mm thru-axle and single hole for the axle on the frame, but needed to add a belt tensioner to keep the belt tight. You can shift at standstill, and each of the nine gears are equally spaced apart, which is not the case for most cassettes.
• Very unique hub motor setup here. It’s large and heavy because it’s full of magnets vs. plastic or metal gears like almost all other ebikes. There’s no rubbing happening, it’s all magnets and that makes it durable, quiet, and capable of regenerative braking and “recoup” mode to recharge the battery. Being a hub motor vs. mid-drive, it can provide fast acceleration and reach higher speeds without requiring the rider to shift as many gears.
• It’s easy to miss, but the Alexrims and front hub are awesome. Notice that they require fewer spokes, that the spokes and nipples are black to match, and that they have some cool looking stickers and offer a bit more width to support the large heavy duty tires.
• The touch screen display is bright, the colors can be inverted (think dark mode with dark background vs. light to reduce distraction at night), and since it senses pressure as well as touch, you can use it more easily with cycling gloves. It’s a little small, and some of the back arrows can feel difficult to press perfectly, but overall it’s a great setup.
• The battery pack can be charged while mounted inside the frame or stored separately, which allows you to keep it in a cool dry location and perhaps check on it more often to extend the life (avoid letting it drain below 20% or get super hot). The default charger offers very high speed 4.5 amp, which is useful considering the nearly 1kwh battery size.
• The updated OMNI display panel uses color, so even though it’s mounted a bit low down vs. on the stem or handlebar, you can kind of tell what mode is selected without having to focus on the small numbers. I love that the button pad for the display is within reaching distance of the left grip, so you don’t have to compromise your grip and steering, and it’s also backlit for easy use at night. It’s simple, with just three buttons (light, +, and -). I was amazed that you can actually adjust walk mode speed! Some ebikes don’t even have a walk mode, so this was amazing to me.
• The horn button is easy to reach, and the sound is instant and very loud. I love that it could keep you safe when riding with cars (since the bike can nearly keep up with automobiles in the city and neighborhoods).
• I believe that every battery that is shipped with a Stromer electric bike, including the ST3, is charged with solar power (which also powers the myStromer AG headquarters in Oberwangen, near Bern / Switzerland).
• Any time you brake with either lever (not just the right one like with ST1 models) power regeneration kicks in and the bike “recoups” some energy, you can also hold the minus button and select from five recoup levels to get a workout or for longer hills to get more energy. Some people ask “can I charge my electric bike by pedaling it” and with this ebike, you can! It would just take a lot of time, and more energy than if you simply plugged it in… because your body has to burn chemical food energy and convert it into mechanical energy (losing heat) and the bike has to re-convert from mechanical into electrical and then chemical to save in the battery pack.
• The bike comes with a SIM card, like a mobile phone, which Stromer pays for. This allows it to get software updates, be unlocked and locked remotely, and also be tracked via GPS for theft recovery. In lock mode, you can set the bike to flash the lights, honk the horn, and nearly sieze the rear wheel so a thief cannot use the bike. The bike can be unlocked with a code on the display, or using proximity to your mobile device.
• Stromer is an established brand dating back to 2009 with global distribution, the ST2 received a Eurobike Gold award, Red Dot Quality Seal award, two Testsieger awards, an Outside magazine award, a Taipei Cycle show award and an iF design award and the ST5 shares many design features and just builds on that platform with a stronger motor and more integrated systems. The ST5 ABS won some awards in 2021.

Cons:

• In past reviews of Stromer electric bikes, I’ve noticed that the plastic cover running along the downtube seemed like it was bending out a bit and could have been more flush or better fitting. That was not the case here, but I still feel it would be nice if the wires were all internally routed through the frame tubing and not tacked on like this. Still, the plastic shield also contains the horn speaker, so perhaps it’s a good compromise overall.
• Stromer offers two stem choices for the ST3 including a more aggressive or more upright version. They both look nice and house cables to create a clean look, but I’m not sure that you could use a third party stem. One downside of their wider clamp stem is that it might not be compatible with all handlebars because some begin to curve or bend closer to the center. A traditional stem is about 35mm wide, but this one was nearly twice that where the clamp is.
• The extra frame material that makes the bike feel sturdy and stable, also adds weight. There’s also the heavier tires, thick sturdy fenders, high capacity battery pack in a metal housing inside the metal frame of the bike, and the gearless direct drive motor. This 72lb ebike is much heavier than average, but once you’re on, it fast and nimble becasue of the high power and sporty geometry.
• Expanding on the heavy weight topic, this ebike has bolt-on axles and fixed fenders which can take additional time to remove for flat fixes and transportation. The fenders could actually get in the way for some bike racks. I appreciate how the diamond frame provides a high top tube for easier use with some racks. In general, I would be careful when lifting the bike to make repairs or transport, and I would consider removing the battery pack temporarily to shave 10.3lbs and make it easier.
• The half-grip twist shift mechanism requires more hand strength than a traditional trigger shifter. I love that it can be shifted at standstill, but it does require some effort, and there are times when riding that I expected it to shift easier… perhaps it was just hard because the bike was brand new?
• The charger is really big, especially with the cords all connected. I love that it’s so fast, and uses a magnetic interface that will unplug if snagged. I kind of wish the main charger was more like the Bosch Standard 4 amp charger in terms of size and form so that it would be easier to transport in a backpack or trunk bag. To me, the loss of 0.5 amps in terms of speed would be well worth the smaller size and lighter weight. As it stands, I would probably not bring the charger along on rides.
• The rear rack is great for what it is, looks streamlined and offers decent capacity at 22.5kg (49lbs) but it doesn’t have bungee loops at the base and isn’t as wide as most others. This means it might not work for child carriers and might not support a wide trunk bag on top (although I did see a nice trunk bag with Tony at the shop that is made by Stromer and is waterproof). At least the rails on the rack appear to be standard gauge and would work with a range of aftermarket panniers in addition to Stromer’s own stuff.
• While it’s nice that Stromer sells exclusively through dealers, so you get the service, proper fitting, and warranty support. The shops seem a bit scattered and limited in North America. Perhaps the high price tag means they can only sell in fancy cities where people can afford it or are replacing their cars? I think they are expanding with some other less expensive models and adding dealers in Europe, so it’s great to see that progress!
• This is a minor complaint, but the display is mounted on the top tube vs. the handlebar or stem, so you have to look down farther and might be distracted from the road while doing so. There is a phone mount option for the stem, so you could use your smartphone for easier and larger display positioning. It’s not a bad setup, just something I’d consider as you ride at high speeds… don’t get distracted.
• No reflective tires here, as apparently they aren’t allowed in Europe? The glossy metallic red frame should be fairly visible… especially with the bright lights and side-viewable running light on the steer tube, but consider adding some reflective stickers to the frame for an even larger visual footprint if you get the black color option.
• If you try to ride the bike without powering on or you just use level zero assist, there will always be some magnetic drag from the motor. It’s not a lot, but this is one of the trade-offs from using a direct drive vs. planetary geared freewheeling hub motor. I also noticed that if you’re pedaling while powering the bike on, it can throw an error because the torque sensor re-calibrates each time. To me, it seems a bit more finicky than other ebike systems.
• It seems like the display panel still takes a while to boot up, it’s not instant (or nearly as fast as Bosch or Yamaha systems), and again, I think it’s best not to pedal the bike while it’s powering on because the torque sensor has to calibrate.

Useful Resources:

• Stromer electric bike dealers.
• Official Stromer website.