Review: Tern’s BYB S11 Is Built For the Multimodal Commuter

Folding bikes are portable, but only in relative terms. Lugging around 25 pounds is no joke, let alone while hoisting a hunk of aluminum and rubber in your hand.

Tern Bicycles, founded by ex-employees of folding-bike giant Dahon, has devoted years to figuring out how to make it easier to move around with a folding bike. To entice you into traveling with yours, it’s made a bewildering array of covers, racks, bags, and hard cases. Tern’s bikes are also notable for innovative, space-saving design tweaks, like making it possible to stand the Tern GSD on its end.

Today, it introduces the BYB, an ultra-compact traveling bike with a footprint of a mere 13.8 inches wide and 31.9 inches tall. It has a unique tri-fold design that lets you keep the handlebars extended to make it easier to trolley (that is, to push it like a suitcase).

I’ve been riding and stowing the Tern BYB for several weeks now, and I’ll be honest: it’s taken me that long to appreciate how greatly it differs from other folding bikes on the market. I didn’t think so at first, but easy trolleying is much more convenient than I thought it would be. The high price tag is probably worth it for the multimodal commuter.

Three Times Lucky

The BYB comes in two versions: the S11 and the P8. I tested the S11, which has Tern’s upgraded drive train, wheels, brakes, saddle, and comfy, ergonomic handlebars. At 27.9 pounds, the S11 also weighs about 2.5 pounds less than the P8, and costs an estimated $2,495 compared to the P8’s $1,295. The P8 also comes in several different colors, while the S11 only comes in matte silver. Both bikes will be available in July.

Tern

While Tern boasts that the BYB has ten separate innovations, the main one is the tri-fold. Tern’s engineers put two hinges in the frame and one on the handle post, which makes folding the bike an extremely precise maneuver. I have the hang of it now (I think), but it took me a solid three days of practice, plus watching and rewatching the instructional video, to nail the fold.

Basically, you have to do your best Jet Li impression while you simultaneously pull the bike apart, twist, lie it down flat, and slip the locking bolt into place. I was eventually able to fold and unfold the bike in under a minute. But I still do not look graceful, or competent, while doing it.

As with all of Tern’s bikes, the BYB has a few useful, nifty features. An anchor bolt, which looks like a little rubber belt, holds the bike in place when it is folded. The patented joint design means that the hinges are really easy to open and close. It also has little spinning wheels that are attached to the bottom of the rack. You can stand the bike on its end on the rack, and the wheels make it easy to push it around.

The rack wasn’t compatible with my Axiom panniers, but Tern notes that it is compatible with smaller panniers, like the Ortlieb Sport Roller. The bike also came with a pop-out cover that attached to the rack for easy stowing on the go.

Hold On Loosely

For the past few weeks, I rode the BYB a few miles a day, on pavement to go downtown to meet a friend for lunch or to swing by my kid’s school, and then back home through a large wooded park by my house.

The BYB boasts a stiffer handlebar post and frame—in fact, the same Doubledeck frame and trapezoidal tubing that made the GSD such a stable ride. There’s always a bit of adjustment when you switch from riding a bike with regular 26-inch wheels to one with clown-car 20-inch wheels, but on the whole I found the BYB to be pretty steady.

The frame was stiff enough and the wheels big enough to jounce through the occasional crack or pothole without a qualm—it didn’t feel that squirrelly, which is a problem with many folding bikes. The Shimano shifters moved smoothly between all 11 gears.

I also rode on gravel and dirt paths and felt pretty stable. As with the Link A7, the bike’s distinctive geometry meant that I felt a little uneasy doing normal bike commuter-y things, like hopping off curbs or going up hills with an incline of greater than 15 degrees. While powering up a big hill, I knew I wasn’t going to pull the front wheel right off the ground with my effort. But I felt as if… maybe I might?

While riding, the bike’s design innovations sometimes got the better of it. For example, the hinge at the base of the handlebar post sometimes felt loose when I was going around a turn. I kept my speed to under 12 miles. Also, the chain is protected by a plastic chain guard that I sometimes had to bang or pop back into place when the pedal’s spindle started rubbing against it. It wasn’t anything I couldn’t fix, but it seemed uncharacteristic of Tern to not correct such a small, annoying flaw.

Hold ‘Em or Fold ‘Em

But it wasn’t until late one night, as I struggled to unload and maneuver another folding bike out of my car and into my house in the dark, that I realized how great the tri-fold was. Other folding bikes do trolley, but they’re not nearly as stable or comfortable to push as the BYB.

After pushing the BYB around my house and driveway for a few weeks, trolleying a folding bike without hand-high handlebars and stabilizing spinner wheels felt as if someone told me to push a suitcase through an airport without a handle. Could I do it? Yes. Would I be irritated and bring it up constantly, at every Thanksgiving, until either I or that person died? Also yes.

If you’re not a multimodal commuter, I’m not sure that the BYB is a true ultra-compact competitor to the Brompton. Brompton’s original M6L is at a comparable weight and is several inches smaller than the BYB P8, and it’s almost a grand cheaper than the BYB S11. And even though Tern makes a suitcase especially for the BYB, you can fit the Brompton into an overhead bin. All things considered, I’d rather bring a folding bike that I don’t have to check.

But if you frequently find yourself going through narrow or crowded subway stations or buses, and at risk of pulling a rotator cuff every time you swing your awkward folded hunk through your office lobby, I can see why the BYB might be an alluring purchase. With a folding bike, how it maneuvers when you’re off it, is almost more important than how it feels when you’re on it.