Bicycles

"Unlimited range" stealth e-bike never needs plugging in

"Unlimited range" stealth e-bi...
Look twice, that's an e-bike – the Nua Electrica to be precise
Look twice, that's an e-bike – the Nua Electrica to be precise
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The Nua Electrica features Brooks leather grips
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The Nua Electrica features Brooks leather grips
The Nua Electrica comes with Shimano brakes
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The Nua Electrica comes with Shimano brakes
Gates carbon belt drive on the Nua Electrica
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Gates carbon belt drive on the Nua Electrica
The entire electric system is housed in the rear hub – batteries and sensors included
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The entire electric system is housed in the rear hub – batteries and sensors included
Look twice, that's an e-bike – the Nua Electrica to be precise
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Look twice, that's an e-bike – the Nua Electrica to be precise
The Nua team developed special 3D-printed sliding dropouts that let you remove the rear wheel without de-tensioning the belt at all
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The Nua team developed special 3D-printed sliding dropouts that let you remove the rear wheel without de-tensioning the belt at all
The first Nua Electrica is already on the road in Houston
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The first Nua Electrica is already on the road in Houston
The Zehus drive unit packs everything, including the battery and sensors, into a 3-kg rear hub
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The Zehus drive unit packs everything, including the battery and sensors, into a 3-kg rear hub

If e-bikes tend to look a little ungainly for your tastes, check out this thing from Barcelona's Nua Bikes. With the motor, sensors and battery built into a discreet hub unit, the Nua Electrica is barely distinguishable from a regular fixie, and its innovative "self-charging" mode means you can get away without ever charging it.

Weighing in at just 13 kg thanks to a full titanium frame, the Nua Electrica is the stealthiest single-speed e-bike we've seen to date. It uses a very cool motor/battery combo unit that we suspect we'll be seeing a lot more of in the coming months and years.

The Zehus Bike+ is an all-in-one hub unit that weighs just 3 kg (6.6 lb) and fits into any frame with a rear wheel dropout 120 mm (4.7 in) or wider. It contains a 250-watt motor, a 160-watt-hour battery, several sensors, a Bluetooth communications system and all the electronics required to run an e-bike.

The Zehus drive unit packs everything, including the battery and sensors, into a 3-kg rear hub
The Zehus drive unit packs everything, including the battery and sensors, into a 3-kg rear hub

Thus, within this one hub, you've got yourself about 30 km (18.6 mi) of full power pedal-assist electric cycling, without a single protruding wire, dash or set of buttons. And that enables builders like Nua, Jitensha, Deus Customs and many others, to produce stunningly minimalistic ebikes that you'd have to look at twice to pick as electrics.

The entire electric system is housed in the rear hub – batteries and sensors included
The entire electric system is housed in the rear hub – batteries and sensors included

You can choose between six cycling modes through an app on your phone, with the most interesting one being a "self charging" mode. Using a tilt sensor built into the back wheel, the drive unit can be set such that it only assists you on uphill climbs and taking off from a dead stop, giving you help where you need it most. And it recharges the battery with regenerative braking, and also sips a bit of power from you when you're pedaling along the flat or going downhill. The company says if you leave it in this mode, you can get around indefinitely without ever charging the thing – obviously this will depend on the terrain, but it's a neat idea.

It also might actually be practical with a bike like the Electrica, which is less than half the weight of some of the chunkier e-bikes going around and should thus be a much less onerous pedal with the e-part switched off.

The first Nua Electrica is already on the road in Houston
The first Nua Electrica is already on the road in Houston

The Electrica uses a Gates carbon belt drive, for maintenance-free reliability and quietness, and it's got a Sugino Pista crankset, a Gilles Berthoud saddle and Brooks leather grips, all of which sound suitably fancy. It also rocks Shimano brakes and Mavic wheels with Hexlox anti-theft locks. Nua has designed and 3D printed a set of special sliding dropouts that let you remove the rear wheel without having to take any tension out of the belt drive, which is a nice touch.

The price? Well, titanium frames, forks and seatposts don't grow on trees. The bike pictured here is around €4,000 (US$4,500). But it's not the Zehus e-hub causing the expense, as other brands like Jitensha are selling similar-looking classic machines for less than half that price using the same drive technology.

Edit: the Electrica, and other Zehus-powered bikes, can certainly be plugged in and charged if you want. Apologies if we were ambiguous on this point.

Sources: Nua Bikes, Zehus

12 comments
highlandboy
No such thing as a free ride. If it is charging from you peddling, it is using your energy. So while it may help you “start” and ride uphill, it will make every flat feel like you are going up hill to some degree until charged. And if it captures energy as you slow down - that is energy you have already expended. It would be interesting to know the efficiency of motion induced recharge.
JimFox
highlandboy3-- pointless negativity, IMO. Many people like me want a bike for EXERCISE so effort expended is the whole point! As the 'e' part can be SWITCHED OFF [which you didn't notice?] your comment is moot. This is a great looking machine which I can't afford but plaudits to the designers.
owlbeyou
My feelings exactly h boy. Plus no mention of being able to recharge by plugging in option, which should be the case. I tried to take a closer look to see what keeps the belt from coming off the gears. I suspect there's a spline in the teeth that prevent this. Too bad it's proprietary cuz you can't readily take this unit and retrofit it on your favorite frame. If you've got a thin build, not too tall and heavy, with a hefty wallet, this Nua may be for you. Otherwise the battery may be too small.
Daishi
First a 160-watt-hour battery will likely not do 20 miles. Other ebikes with almost 4x the battery capacity are only optimistically rated for 2.5x the range. It's probably generous to give it 13 miles of range. Secondly it's bad for battery chemistry to be fully depleted to it's useful to have a larger battery and not have to fully cycle it. Lastly I agree with highlandboy about regenerating energy while peddling being a generally bad idea. That just means like it will always feel like you are riding in sand or going up hill even when you aren't. It's the opposite of what ebikes are for. There are always efficiency losses and you recoup much less energy than you probably expect by peddling against the regenerative system. I do like regen systems as an alternative to using the brakes. It takes an hour on a stationary bicycle to generate a little over a penny worth of an electricity (100 watts) and that's using all your energy not just a portion of it. Leeching 1/3 of your energy on a flat surface you would peddle for 3 hours to make 100 watts (a penny worth) of power. The only argument for doing that over just plugging it in is if you think non-ebikes are too easy and want the ride to be harder. It's the opposite of what most ebikes do. As batteries get cheaper and ebikes are starting to ship with 1000 or more watt-hour batteries I think something like this will continue to make less sense going forward.
Expanded Viewpoint
Gadgets like this are mainly for the people with more dollars than sense. When I throw my leg over the saddle of my bike, it's to get some good exercise and enjoy the outdoors, not to commute to work or look chic. Of course I keep the tires pumped up firm to minimize the effort needed to go any given distance, as I don't ride much these days, being so busy with my work projects, and there's no need to make it even harder than it needs to be to burn off some extra calories!
craig_a
I like it! I'm glad someone is making assist with a slope sensor. Ideally I want a bike that makes the hills disappear without me constantly adjusting things. The part about "sips a bit of power while pedaling on the flat" is concerning, but I suppose if you don't have easy access to charging it's an interesting idea. Basically storing power slowly over a long period so it's available in small bursts when you need it.
Paul Muad'Dib
No mention of whether or not you can plug it in to charge the battery. If you can't I'm not interested.
Rustin Lee Haase
The S&M (sales and marketing) lie of "self charging" seems to have spilled over into bicycles here. With cars, the lie covers up the fact that "self charging" vehicles use a gas engine to charge the batteries. With bikes, it's the rider. Then there's regenerative braking so we could say that any device, car or bike, that does that is also "self charging" "self charging"...what a bunch of hippie dippy phoney baloney. ...I've got a perpetual motion machine to sell you. It's self charging.
toyhouse
Folks are still having a hard time defining ebikes and their mission profile years on now. You're supposed to get some exercise on them. You're supposed to ride them to work without arriving sweaty. Look at those lazy slobs on ebikes says the weekend racer,( I've heard that more than once),. They're power-assisted bicycles, they're electric motorcycle/moped cross-overs, exercise devices, green transpo. Endless possibilities with no right nor wrongs. Truth is, there's never been anything like them and I want one! Just not this crazy overpriced-yet-again ebike. Sorry. No charge port as someone mentioned. A drag during normal pedaling for charging? No thanks for me but for others?.... go for it! I'll get my exercise some other way. I wonder about battery lion/lipo safety and or longevity wrapped around a hot electric motor. Battery replacement cant be an easy thing either. I get it though - it's stealth.
MikeRyanc95317ae2315443b
I like the idea of this bike and while there may be a few shortcomings, what stops me is the price tag. For the $4,500 USD (6,071.85 CAD) plus tax, I can pick up a nice new Honda Monkey bike, Honda Cub or a Grom and still have way over a grand in my pocket.