Apparently in Japan there’s a type of bicycle called the Mamarachi or “mom bike” that’s easy to approach, with a low stand over height, and very useful, because of its front and rear rack provisions. These bicycles are frequently used to transport children and goods around town and they inspired Kiyoshi Iwai, a Japanese steel worker, to create a modernized electric assist version. The CERO One is the culmination and evolution of that creative endeavor and Kiyoshi and his business partner Felipe are launching it now in 20117 after three years of work. The One is what I would describe as a compact cargo e-bike, it’s capable and sturdy but doesn’t require the garage or apartment space of full sized models like the Yuba Spicy Curry. Measuring 72″ long and just 15″ wide when the handlebar is turned, it will fit into elevators, slide into bike racks, and squeeze into closets (when tipped up onto the rear wheel). You can only get this electric bicycle in one frame size at the moment, but the stem is highly adjustable and they claim it fits riders from 5’4″ to 6’2″. The stem telescopes up 100 mm and 110 mm stem adjusts from 0° to 90° so you could effectively double the height or position it way out to extend reach. Both adjustment parts are made by Satori and I appreciate the two-bolt clamp that will keep this stem secure on long bumpy rides. Many cheaper adjustable angle stems only use one bolt and can rattle loose as you ride over cracks and go off curbs. For this video review, I took the CERO One across grass, reached the top assisted speed of 20 mph, and forced a motor stall on a small hill. The bike felt pretty good even though it’s built around a rigid frame. There’s no suspension fork, seat post shock, or large plush saddle. Instead, you get a swept-back gullwing style handlebar with premium ergonomic grips and an active Ergon saddle. The tires are wider than normal at 2.15″ diameter and have a 30 to 55 PSI rating so you can lower the pressure a bit to improve comfort at the cost of efficiency. This is a more active bike, one that requires you to pedal vs. relying on a throttle mechanism, but it gets incredible range (between 35 and 90 miles depending on the level of assist chosen). The unique 26″ rear wheel and 20″ front wheel layout keeps the front rack low and steady, out of your view, and improves strength. It turns corners tight, has a walk mode feature (hold the down arrow to activate and then hold again to make it go forward slowly).
Driving the bike is a geared mid-motor from Shimano, the same company that produces the hydraulic disc brakes and 10-speed drivetrain. Their STePs electric bike system is light, efficient, and still very capable offering 50 Newton meters of torque, but it’s not as strong as the Bosch CX which offers 75 Nm or the Brose which offers 90 Nm. By comparison, many high-powered hub motors offer 20 to 40 Nm. I mention all of this because we’re talking about a cargo bike here. And it doesn’t have a NuVinci CVT or internally geared hub that can be shifted at standstill. You have to plan your shifts in advance and leverage low gears to get the motor to climb effectively. If you stop on a hill without shifting down and have a loaded bike, the motor may stall when you start from zero again. This motor is relatively quiet but does produce an electronic whine as you pedal faster or use the highest two assist levels. It is bolted onto a custom bottom bracket mount and keeps weight very low and balanced on the frame. Same thing goes for the 5.8 lb battery pack, it’s low and mounted near the motor. I love how CERO considered chain movement when mounting the motor and double-leg kickstand, notice the little sprocket just below the chainring. This raises the chain so it won’t rub and it also keeps it tight as you ride over bumpy terrain. Unfortunately, it seems like they forgot to add a slap guard sticker on top of the chainstay (or just didn’t think this was an issue). Sometimes, especially on mountain bikes, the chain will bounce into and chip the paint on the right chain stay. This is something you can add yourself later. I do love the four color choices, especially the white because it will be the most visible at night, and would want to keep the bike looking as clean and new as possible given the $3,399 price point. Felipe explained that they really scrutinized the paint and chose a 50/50 blend of gloss and matte to reduce fingerprints. Some final thoughts on the motor, it turns a 38 tooth sprocket which is protected by a plastic guard on the outside, it would be nice to have a guide here to keep the chain from falling off towards the inside but I didn’t notice this being an issue during my test rides. The 10-speed drivetrain is perfect for this bike and even has a Shadow Plus clutch to increase tension and reduce chain bounce if you are on rough streets. Just push the little grey lever into the up position. Leaving it down will make shifting slightly easier. And back to those brakes, with 180 mm / 160 mm you get plenty of stopping power and the adjustable reach levers are great for riders with small hands or those days when you might have puffy gloves on.
Powering the One is Shimano’s new BT-E8010 downtube mounted battery. It is way better than their older pack and here’s why… you get more energy (36 volts by 14 amp hours), it’s nearly the same physical size, it still slides out vs. clicking down (so the downtube and top tube can be very close together and lower the stand over height of the bike), and it uses a single charger interface vs. requiring a dongle. The electric bike charger itself is also improved, offering 4 Amps of power flow vs. just 2 or 3 as with most other electric bikes. The charger is a little heavy and bulky, but I’m assuming it’s safe and durable because Shimano is a premium brand with many years of experience doing electric bikes and electronic shifting. You can easily toss the charger into one of the baskets or a trunk bag on the rear rack to fill the battery at work or a friend’s house. Notice how good the black accents like those custom plastic venders, the grips, saddle, tires, motor casing, and battery all look on this bike. The thing is well balanced visually and you will be able to keep it looking nice because the battery and display are removable. It’s useful for lifting the bike as well, you can reduce weight by taking off all of the rack systems, the battery and display, and both wheels (which feature quick release). This does present the challenge of locking however, make sure you lock both wheels for longer stops. The rear wheel is easy to secure with the included ABUS cafe lock, and I love that it uses the same key as the battery. Consider a u-lock and cable to secure the front wheel and the rest of the frame.
Activating the CERO One is quick and intuitive. Once the battery has been charged and properly mounted, just hold the power button on the left side of the display for a few seconds. This will allow it to boot up and show your current speed, assist level, trip stats, and battery percentage. Hooray for Shimano, going with battery percentage vs. a five or ten bar battery infographic. It’s a lot more precise this way and you can use the percentage in combination with the range estimator menus to plan rides. As you arrow up and down through the different levels of assist, the range readout will dynamically update based on battery level, recent ride activity, and that level of power being used. Shimano has enlarged their display to make it easy to read and the transflective LCD works well in low and high light conditions. The button pad is easy to reach and interact with when riding without taking your left hand off the grip, and there’s an annoying beep sound that chimes each time you do make a selection. Thankfully, by holding the up and down keys simultaneously, you can enter into the settings menu and turn off this beep, switch from metric to standard, even change the font color from black on white to white on black (much less distracting for night riding). Perhaps the only complaint I have about the Shimano STePs ebike system as of today is that it does not have a USB power port to tap into like Bosch and others. This is handy for charging a phone on the go, especially with the new enlarged 504 watt hour battery pack. You may arrive at your destination with plenty of juice to spare but no way to access it for your ailing phone. All automobiles have 12-volt DC adapters (those round things) to plug into, and many newer cars have USB… so when you pay $3.4k for an electric bike to replace your car, I feel that it should include some of these creature comforts. Note that the smaller Bosch Purion display does not have a functional USB charger, so the Shimano system is not alone in lacking this.
At the end of the day, I feel like the CERO One electric bike could either be a compact high-quality commuter platform, a capable cargo bike for a delivery person (food, boxes, etc.), or a parent’s bike for him or her. The design and colors make it appealing to men or women, in my opinion, and it would definitely take the effort out of having to pull a trailer, add 40 lbs of child seat + child, or a big load of groceries. This is a capable, high quality platform that I would expect to last well. Even if CERO went out of business someday, Shimano isn’t going anywhere and will support this battery type for years to come. I definitely appreciate the drive system improvements over prior year and have been excited to see a bunch of compact cargo capable models lately such as the Orbea Katu-E 10 and Riese & Müller Tinker. Perhaps something like the BESV PSA1 would be more comfortable because it has suspension, and it is lighter, but it’s just not going to be as powerful or efficient. The One has filled a niche and I’m excited to see how it does in the coming years, kudos to the team. Big thanks to CERO for partnering with me on this review and meeting me in Santa Clara to film. I always enjoy meeting the team behind the product and really digging in… and I absolutely love the bottle provisions on the front rack and bosses :D
- I was really impressed that they added a pulley wheel to keep the chain clear of the double-leg kickstand, this way the chain won’t rub when the stand is deployed! I was then immediately disappointed that the top of the chainstay does not have a clear plastic slap guard because it could get chipped up over time if you ride on bumpy terrain in high gears frequently, consider adding your own for ~$12
- I love that this e-bike comes in four colors, the white appeals to me because it would be the most visible from the side when riding at night but all models have reflective paint accents and the black blends the battery, motor, fenders, and baskets the best
- Most cargo bikes are long and wide, I love how the CERO One is only 72 inches long (that’s about the size of a regular bike) and has an adjustable stem that lets you turn the bar sideways to make it narrower
- Whether you use this electric bike for cargo hauling or not, it’s very sturdy and nimble, the racks can be removed so maybe you only leave the rear on with a Yepp! child seat to reduce weight and keep it narrower? Many possibilities
- Aside from the compact size and sturdy racks, one thing that really differentiates this bike is how easy it is to mount and stand over because of the mid-step frame and smaller front wheel, it feels stiff and strong but isn’t so overwhelming or difficult to mount
- In the video review I kept commenting on the weight of ~56 lbs but I actually think this is great with both racks on the bike, fenders, lights, and larger tires… you can run the tires tubeless to reduce weight
- The battery charges quickly thanks to a 4 Amp charger, it’s removable to reduce weight or charge separately for convenience (like if you commute) and the charger only has one plug now! No more dongle adapter which was easy to lose on older Shimano battery designs
- I like have a range of gear choices (especially with a potentially loaded bike) and you get a quality 10-speed Shimano drivetrain here with Shadow Plus (the little grey lever) so you can position it up to tighten the chain if you ride fast on bumpy streets or down to loosen it for easier shifting
- The Shimano hydraulic disc brakes perform very well, in some ways, the 180 mm front rotor is overkill because you also get a mechanical advantage from the smaller 20″ wheel diameter, these brakes are easy to use and have adjustable levers which is great for people with smaller hands
- The racks that come stock with the bike are very well done, the rear offers 75 lbs of carrying capacity and the front offers 55 lbs of carrying capacity which is way above average, they look good and have many mounting points but may require larger pannier clips because the side tubing is thicker
- I came into this review thinking the bike did not have bottle cage mounts and then Felipe showed me that it does! There are two sets of bosses (one on either side of the front rack) and they include 10 mm spacers and mounting screws apparently, this positions your fluids or accessories within reach while riding and means you don’t have to leave them in the basket where they could roll around as you maneuver the bike
- Very nice touch points, the Ergon saddle and Ergon locking grips are durable and active but tend to reduce hand and bottom fatigue which is key on a bike with no suspension
- Unique pedal choice, the nylon platforms with imbedded grip here provide surface area and traction without the dangers of sharp pins that could scrape your leg if you foot comes off, it’s a good compromise and works well on this sort of bike even if your shoes get wet
- The Shimano display really helps you overcome range anxiety because it shows a battery capacity percentage as apposed to some five-bar infographic and there’s a dynamic range calculation for each level of assist
- CERO has been in the works for several years so even though they are doing a Kickstarter campaign and this is their first official release, they are more established than some other startup ebike companies and you get an excellent two year comprehensive warranty on the bike, the company is based in Los Angeles, California
- The headlight is mounted well, beneath the front rack, so it won’t get blocked… but it doesn’t point where you steer because the rack is frame mounted for improved strength
- There’s no suspension on this bike so, depending on where you ride, you might want to reduce the air pressure in the tires to improve comfort a bit (the range is 30 to 55 PSI), consider a 30.9 mm seat post suspension but note that it will raise the minimum saddle height by about three inches
- The new battery pack is relatively lightweight at ~5.8 lbs considering how much electricity it can hold (504 watt hours) but it isn’t as easy to carry as the older one, there isn’t a clear lip to grip at the top like there used to be and there’s no loop like the similar looking Bosch battery has
- I love that the new Shimano STePs ebike charger is fast, putting out 4 Amps vs. just 2 or 3, but it’s pretty large and a bit heavy at 2.2 lbs vs. Bosch’s 4 Amp charger which weighs ~1.7 lbs
- The chainring has a plastic protector to help pants and skirts slough over and stay clean but it does not have a full chain cover or a chain guide to reduce drops, just a minor question or consideration compared to some other models I have seen
- The Shimano STePs mid-motor used here does not offer shift detection and you cannot shift at standstill since the drivetrain uses a traditional cassette and derailleur, I mention this because it could be easier to mash gears if you’re starting out with a heavy load and shifting while pedaling, try to ease off on pedal torque just before you shift to keep the chain, sprockets, and derailleur in good shape
- The shifter cables, electrical wires, and brake lines are well hidden below the downtube, but they are not internally routed the way that some other e-bikes are, this clutters the visual appearance and exposes them to more dirt and water but also makes servicing the bike easier
- Minor gripe or area for future consideration, I wish there was a USB port to tap into the battery and keep your phone, music player, or additional electronic accessories filled (the Bosch Intuvia display offers this)