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2018 Oyama CX E8D II review: probably the nicest folding electric bicycle I’ve ever ridden

Electric bicycles are becoming increasingly popular forms of personal electric transportation, and rightfully so. They make it super easy to zip around crowded cities, usually arriving faster than cars, buses and just about every other alternative.

But one of the few downsides of electric bicycles is that they are usually fairly large and bulky, meaning they’ll take up a big chunk of your apartment or car – if they even fit. That’s where folding electric bicycles come in, and the 2018 Oyama CX E8D II is perhaps one of the nicest examples of a folding electric bicycle that I’ve ever seen.

Generally speaking, folding electric bicycles are usually something of a budget category. It’s the segment where companies often try to offer simpler, less powerful yet more affordable options.

Outside of a few examples like the E-JOE powerhouse we reviewed, electric folding bikes usually don’t offer much to write home about.

That’s why the Oyama came as such an awesome surprise when I unboxed it.

As I shucked its foam and cardboard protection like a motorized, two-wheeled ear of corn, I was amazed at the quality of the components that were revealed.

How are the parts?

Lightweight aluminum alloy frame? Check.

Theft resistant 378 Wh battery hidden inside the frame, yet still removable for charging? Check.

Hydraulic disc brakes? With embedded brake cutoffs? Check.

350 W Aikema (a higher quality motor brand, more on that later) hub motor? Check.

Schwalbe Big Apple 2.0 reflective tires? Check.

Integrated headlight powered by the main pack? Check.

8-speed Shimano ALTUS? Check.

3-point folding mechanism? Check.

USB charging for my phone while I ride? Check.

Robust rack and fenders that actually work? Check.

All of this in a 42 lb (19 kg) package, which believe it or not is fairly light by e-bike standards.

The list just goes on and on. While I was expecting just another basic, run of the mill electric folding bike, what I got was a really well thought out, well designed e-bike.

One thing I didn’t get though was a hand throttle. That’s because the Oyama is a Class 1 electric bicycle, meaning it is pedal-assist only. If you want motor power, you’ve got to add at least a little bit of your own pedal power. As soon as you start pedaling, the bike should do the rest to kick in the extra juice.

This also came as a bit of a surprise to me.

You see, I’m not really a cyclist. It’s not that I’m lazy or out of shape. I run between 3 to 5 miles a day and could pedal if I wanted to. It’s just that I generally think of electric bicycles more like little electric motorcycles that don’t require me to get a motorcycle license or pay for insurance or registration. They’re for getting around quickly and effortlessly.

Before I got the 2018 Oyama CX E8 DII, I don’t think I had actually pedaled in a few years, and the last time I did was only because my e-bike battery once died and I had to pedal home like a neanderthal.

But hey, when in Rome right? So I figured I’d give this whole pedal assist thing the ole’ college try.

How well does it ride?

I took the Oyama out for our first ride together, jumped on the saddle, cranked the pedals and I was off!

Sort of. I mean, I felt a mild electric boost, but I was still doing the lion’s share of the work.

A quick glance at the display told me why. I was in Assist Level 1.

Click. click. click. click. click. click. click. Level 8. There we go, that’s better.

I tried the pedals again and this time the Oyama took off like an electric bat out of hell, with me wholly unprepared and nearly slipping off the back of the saddle. Now we’re talking!

I tried again, this time prepared for the intense acceleration of Assist Level 8, and now I was really flying.

In the highest level of assist I was suddenly zipping up to 15 mph (24 km/h) or so with just a tiny bit of pedaling effort. It felt like I was using a cheat code, seriously.

Then when I actually tried to pedal a bit harder I found that I could maintain 18 mph (29 km/h) easily.

Soon I was cruising all around town on this thing, pedaling away with the smile of a gleeful six year old that just learned to ride without training wheels.

The interesting part of the pedal assist system in the Oyama is that it can really sense when it is needed. The hardest part of pedaling is starting from a dead stop, and that’s precisely when the pedal assist was providing the most power. I could feel it start to taper off as I passed through 10 mph (16 km/h) or so, but by that point I had sufficient momentum that I only needed a gentle boost from the motor to help maintain higher speeds.

The motor was actually kicking in when I needed it and reducing when I didn’t, all without any hand throttle to control it.

Somehow, despite my original aversion to pedaling, I soon realized I was actually having fun using my legs. I even started dropping the assist level down from 8, the highest level, to a more reasonable 5 or 6. I could feel that I was making an honest effort, but it was just enough to get those endorphins going without being so much that I was sweating and tired.

Despite the fact that I was having to physically exert myself, the ride was incredibly comfortable. The saddle was actually pleasant to sit on, which was a nice change. Many lower priced e-bikes come with saddles that feel like they are made from concrete, but the Oyama’s was somehow both small and yet still comfortable.

The handlebars are a comfortable height and distance and the grips are nicely padded without feeling chunky.

The brakes also work amazingly well. I’m used to mechanical brakes, and had to get used to using just a light two-finger touch on these hydraulic brakes. That’s all that is needed – no more wrestling with the brakes when stopping from high speed.

The motor was also whisper quiet, which is weird for these smaller geared motors that normally have a more pronounced whine to them.

Unlike most cheaper electric bicycles that use Bafang or other similar motors, the Oyama uses an Aikema motor.

These motors are known for being higher quality, quieter and generally better grade motors.

All of this added up to an overall feeling that each component on the Oyama just felt well planned and designed – a pleasant surprise in an industry where margins often come ahead of user experiences.

What type of riding can it handle?

After I fell in love with the bike, I found myself trying it out in new and ever more arduous places.

Of course it faired just fine in the bike lane, but what about on the road with cars? In the highest assist level and with only moderate pedaling by yours truly, I was keeping up with cars in Boston city streets.

As I became increasingly impressed with what the bike could handle, I started riding off curbs on purpose, grinning as the little e-bike pulled off the maneuver flawlessly and didn’t even protest.

To give it some different terrain I headed for the dirt paths and boardwalks over the nature reserves in North Cambridge, where the big 2 inch Schwalbe tires absorbed the boards and kept the ride perfectly pleasant.

Up until this point the Oyama had taken everything I had thrown at it, smiled, and just kept going.

Time to bump it up a notch. Could this city bike handle the countryside?

Next I hit the nature trails, one of my favorite running spots, complete with overgrowth, tall grasses, random stumps and slippery uphill climbs over loose dirt. Keep in mind that this is a folding bike meant for city commuting. What I was asking of it was well above its pay grade.

But in the moment, the Oyama didn’t seem to care what it was supposed to be designed for, it only cared about moving forward. And forward it went. Over the dirt, over the stumps, up the hills and through the gravel. It overcame nearly every obstacle and terrain I could find until I finally had to help lift it over a fallen log blocking the trail and under a vine waiting to clothesline me. Perhaps I could have hopped the log if I had really tried, but by that point I figured the Oyama had made its point.

So while this is still of course a city commuter bike, the build quality is definitely far above that of any other city e-folder I’ve ridden, and the Oyama has the power to handle much more than just bike lanes and occasional curb hops.

How far can it go?

Really far. In fact, I’m not even sure exactly how far because the battery just stays so charged up that I never managed to fully drain it.

I charged it around once a week and used it nearly every day. After a number of trips I had reached around 20 miles and still had almost half of the battery capacity left.

I could determine this because not only does the display show you a neat little battery diagram, but it also tells you the exact battery voltage – perfect for battery nerds like me!

I would have loved to test how far it could go on a full charge by draining it all the way but I would have needed to ride for hours and hours to finally drain the battery. I just didn’t have anywhere I could go that would take that long.

Calculating exact ranges on pedal assist bicycles is notoriously difficult because everyone pedals differently. Many companies try to claim outrageous ranges by putting a professional cyclist on the bike and demonstrating a “possible” range under ideal conditions.

Oyama doesn’t even a list a range on their website, perhaps for the very reason that pedal assist range is so variable and subjective. They don’t try to sell you on unrealistic ranges, rather they just pitch the quality of the bike and let it do the talking.

From personal experience, and considering the fact that I was riding around in the highest power setting much of the time, I feel confident wagering that the bike could make it at least 40 miles (64 km) with light to moderate pedaling, and probably much more with a lower assist level and more user-pedaling.

How well does it fold?

While riding the Oyama, I found myself constantly forgetting that it was a folding bicycle. It just didn’t feel small or creaky or awkward the way many other e-folders that I’ve ridden have felt.

But that doesn’t mean the Oyama can’t fold as well as the rest of them. In addition to the standard two points of folding, one at the middle of the frame and one at the handlebars, the Oyama also has a third folding point at the top of the handlebars. That one allows the handlebars to rotate forward and make the bike just a bit smaller in folded form, and also helps to protect the brake levers, display and other goodies mounted on the handlebars.

The levers that control the folding mechanism are nicely machined and feel really solid. Both have nice locks as well that prevent accidental folding, and the mechanism just feels really solid.

And like pretty much every other folding bicycle, the pedals fold in as well, which is good for making the bike more narrow, especially if you like to park it against a wall in your apartment or need to fit it in a narrow trunk.

What are the downsides?

Even though I’ve been gushing about this bike, it’s not entirely perfect.

The ride isn’t as nice as a bike with suspension, though the 2 inch tires help to absorb the smaller bumps.

Also, the power button was a pet peeve for me. You only need to hold it for a second or so to turn it on, but you have to hold it down for probably 5 full seconds to shut the bike off. If you don’t hold it down long enough, the bike doesn’t shut down all the way and just goes into “standby” mode. When I would hop off and park the bike, I found myself just standing there awkwardly while holding the button and waiting for it to turn off before I could lock it and walk away.

Lastly, the headlight is always on when the e-bike is on. Perhaps there’s an option in the display somewhere to turn it off, but I couldn’t find it. It probably only draws a couple watts of power so I’m not really worried about the battery, but I hate blinding people as I roll by during the day, especially when maneuvering the bike around inside my building. And since the power button takes so long to turn the bike off, sometimes I’m blinding people in the elevator for 5 seconds straight while awkwardly smiling and gesturing towards the buttons on the display.

I have to admit though that my complaints about the bike are all pretty nitpicky and minor in comparison to how much I enjoyed it. I’d rather have a headlight that stays on than no headlight at all!

Who is this bike for?

I think the best use for the Oyama is the type of rider that wants an e-bike for the cycling aspect and not someone looking for a folding moped. Even though the Oyama is quite powerful, it still gives you the experience of riding a bicycle instead of a little motorcycle.

The entire time I was riding I felt like I was pedaling without feeling like I was working. So I got the joy of cycling without the intense effort, which is pretty amazing when you think about it.

For anyone who enjoys cycling but wishes they could go a bit faster while at the same time working less hard, the Oyama CX E8D II is for you. I was able to easily explore the city without working up a sweat, even in July.

It would also be especially good for students and commuters who want a small, lightweight e-bike that can be easily taken in a dorm, classroom, office, train or other tight space while still offering a ride comparable to a larger bicycle.

Kim Merrill, a PR rep for Oyama, told me how he generally uses it for city riding after a long day on the MTB trails:

“I am a big mountain biker and over the past couple years have taken a couple of electric folding bikes with me on various trips around the Southwest. I ride hard on the mountain bikes, then use the eFolders to get out and see the nooks and crannies of the town we are staying in … Mammoth Mountain, Big Bear Resort, Sedona, Springdale near Zion National Park, etc. I leave my truck in the parking lot and explore on the eFolder … after a hard day of riding the electric aspect is great … don’t have to worry about hills! Also the folding nature allows the bikes to transport easily, and store easily in the hotel or condo.”

Where can you get it?

The CX E8DII is available on Oyama’s website for $1,899. Considering the premium bicycle that you’re getting, I think that’s a very fair price. I’ve seen much more expensive e-bikes with much lower quality craftsmanship.

However, if you’d like a premium bike with a little less power and range, you can grab the previous model, the CX E8D, for just $1,299. It comes with a 250 W motor instead of 350 W and the battery is reduced from 378 Wh to 238 Wh.

Between the two of them, I definitely prefer the Series 2 with the 350 W motor and the larger battery. This bike will certainly be my go-to machine from now on for anytime I want to go for a ride and have my legs get a little work… just not too much work!

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Avatar for Micah Toll Micah Toll

Micah Toll is a personal electric vehicle enthusiast, battery nerd and author of the Amazon #1 bestselling books DIY Lithium Batteries, DIY Solar Power and the Ultimate DIY Ebike Guide.

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