Anyone who's ridden one of Stromer's e-bikes has likely come away impressed. With the new ST2S, Stromer takes some of the highest-end bike parts offered, adds some innovative e-bike features, and brings it all to life with the largest and most powerful e-bike battery on the market. Read on to see how the e-bike ante just got upped.
- 983 watt-hour battery
- SYNO Drive motor
- 110 miles per charge
- 28mph top speed with pedaling / 12mph top speed boost mode
- Available in 17in, 20in and 22in sizes
- XTR Di2 11-speed drivetrain
- BMC carbon fork
- DT Swiss thru-axle wheels
- Built in touch screen
- 1,600-lumen headlight
- Phone app compatible for bike tracking and locking if stolen
- 58lbs / 26.3kg
Electronic drivetrains and e-bikes seem made for each other
Frame and equipment
The ST2S is alloy, with the monster battery stored in the down tube. Because of this, the frame tubes are quite massive, which Stromer takes advantage of by placing a touchscreen LCD display in the top tube, near the stem.
Shimano's XTR Di2 provides the gearing – and comes across like it could have been made for this e-bike (rather than the MTBs it's intended for). Like always, Shimano's Di2 shifts perfectly every time with zero fuss, and that precision just adds to refinement of the ST2S. To me, electronic shifting on an e-bike just seems to make sense. Buttons for the motor, buttons for the shifting, it lines up nicely. The ST2S does have Shimano's Di2 battery integrated into the frame, meaning the shifting does not run off the bike's battery. However, the Di2 battery can be charged through the USB port in the front headlight should you run low while riding.
A USB port sits within the daytime running lights to power your electronics or revive a flat Di2 battery
Rolling with the biggest and baddest battery certainly has its advantages, not least of which is its huge 110-mile range. The mighty powerpack allowed Stromer to ride the entire first stage of the Tour of California on a single charge.
Charging is simple with the external port
There are running lights up front, as well as a 1600 lumen headlight, and a rear brake light that activates when you squeeze the brakes. The push screen computer can connect to a smartphone, and Stromer has an app that lets you make upgrades, allows you to lock the bike remotely, and even sends a text if the bike thinks it has been stolen. If it was stolen, you can disable the bike through your phone, and track its location.
Stromer e-bikes ride like no other e-bike I've swung a leg over. Their prodigious power comes on smoothly and capably, and the fit and finish all feel very clean and purposeful. This ST2S model takes all those positive attributes and turns them a bit up.
At 58lb and with its massively oversize alloy frame, it's a big, heavy bike, there's no denying that, but it rides smoothly, and hides its weight and bulk well behind a seamless wave of energy. The motor delivers power consistently – there's no lag, then big, sometimes overwhelming hit of power like on some other e-bikes, just lots of useable torque to bring you up to speed. Step hard on the pedals and the rush of torque accelerating you towards the horizon is addictive – at least, that is, until you hit the 28mph limit. After that it feels like a big, heavy bike again.
As mentioned above, the pairing of Shimano's XTR Di2 drivetrain is another real highlight. It feels very natural to simply tap a button for shifts on an e-bike, and the tiny whir of the derailleur's motor fits right in with the slight hum of the hub motor. It's a combination that adds to the bike's exceptionally refined, modern feel.
With the battery residing in the entire length of the down tube and the motor in the rear hub, the bulk of the weight is central and low to the ground. It handles well but like all big, heavy things, does feel better at speed. There's simply no getting around that it's 58lbs, and going slowly it can feel awkward.
With thru axles and disc brakes it's clear Stromer understands high-end
While this is a pedal-assist e-bike – meaning your pedaling activates the motor – it also feature a 'boost' mode. Hold down the + button, and the ST2S will propel you on its own up to 12mph. Stromer does point out that this is the quickest way to drain the battery.
One thing I've noticed while riding Stromer's e-bikes, and it's on ST2S as well, is the placement of the computer in the top tube. While being neatly integrated, to actually read the information requires a long look away from the road. It's behind the stem, so it's an unnatural spot to try to quickly glance at information.
Nicely informative, able to link to your smartphone and apps, but not in the ideal position behind the stem nested in the top tube
ST2S vs the competition
Stromer is basically the Tesla of e-bikes and could actually replace a car a lot of the time. The brand is unapologetically at the top end of the e-bike spectrum, and has the batteries, motors, and technology to rightfully be there. I'd consider this a long-distance machine, one that's very eager to nick off the miles, and get you to your destination in record time. It wouldn't be my first choice for purely urban e-bike transportation in a chaotic city, but if you regularly need to go a long way and your pockets are deep enough, the ST2S resides in its own class.