The Evelo Aurora Arrives, Part 1
Even with the momentary hitch in ordering my Evelo Aurora due to a frame color change, the bike arrived via FedEx six days after ordering – not all that bad. It shipped partially disassembled in one carton, a carton which showed signs of manhandling. It was punched through in a non-critical area, but I was still understandably concerned that something might be bent by the lack of finesse in handling the 70-pound monster. Evelo added my comment to the roster, and told me that they are already in the process of upgrading their packaging to thwart the gorillas. It’s obviously in their own best interests to limit the risk of damage.
But my concern was groundless, as the only damage was elsewhere, a few minor paint scuffs in the bike’s shiny black rear rack frame. I’d be doing worse to it, in time. The bike comes almost ready to go, and all you need to do is mount the front wheel, stick the handlebars on, and screw in the pedals. There are no tedious adjustments that involve functionality. The needed tools are supplied with the bike, along with a basic assembly and user manual. For those who dislike following printed instructions, Evelo promotes viewing their online assembly video for each model.
Although I spent a college summer assembling cheap bikes in a sweatshop decades ago, I took my sweet time putting the thing together because first, it was my own bike and second, the hardware has changed a lot in the bicycle world since dinosaurs roamed the earth. Didn’t take all that long and, in the end, I had me an e-lectric velocipede! My late bud Benny Franklin would have been excited were he here to see it. Tommy the E-Man would have, too.
Tempering my craven desire to give the Aurora a spin, I actually followed the instructions and put its big lithium battery on the charger first. The spare battery and charger I’d ordered came in a second small carton, and I plugged that one in too, as much to test the charger as anything else. Once the bike’s pack was charged, I put it in, connected the bike’s plug to it, and wondered what was supposed to happen. There’s no “on switch”, but there is a key lock inside a housing where the battery lives, and I wondered if it was supposed to control juice as well.
See, the manual didn’t mention anything more after assembly than to just hop on, go, and maybe do a procedure to break-in the twin disk brakes. Have fun! But I wasn’t having fun yet. The display on the handlebar stayed blank. So I pushed the assortment of three buttons near one handlebar grip, and dutifully checked cabling of the brakes to ensure that nothing was kicking a “safety” in that would cut power to the motor. Still nothing. I installed the spare battery, with the same non-results. With the strings of luck I get from time to time, I feared that maybe I had a dead player. I emailed Evelo Customer Service to say that I couldn’t get the bike alive, and were there any electrical checks I could do to troubleshoot?
They promptly sent back two things with an apologetic reply: an illustrated description of how to check the battery with a voltmeter, and a new manual describing the features and how to operate the recently-revised LCD display with its control buttons. Turns out it hadn’t been included in the carton, as the changeover in production had just occurred and Evelo’s version of the instructions apparently were MIA when the bike was boxed.
Voila! I was supposed to hold down the central button for a couple of seconds to turn the system on. I did, and it did. Imagine my relief. The display lit up and the Aurora was ready to rock! I was too surprised, excited, and relieved to feel stupid. For the record, the display indicates total miles, trip miles since last turned on, battery charge level, current speed, pedal-assist level chosen, how many watts the motor is currently using, and any error codes should the system develop problems. The buttons also control the standard LED headlight and taillight.
One handy feature that the display offers is a USB charge port in its side, protected by a tethered rubber plug. In my case, I can use this to power my GPS off the main battery pack, to give me a much longer run time than the GPS’ little built-in battery can supply. Considering the places I go and the trails I take, I consider this feature to be fairly awesome.
Even its kickstand is better than expected, with a decent reach outward, and a broad rubber foot to discourage sinking into softer surfaces. It works great in practice, holding up the heavier Aurora much better than the Raleigh’s kickstand does it. No replacements needed here!
The pedal-assist system on the Aurora is motion-sensitive rather than torque or pressure-sensitive. I prefer this, as I don’t want the bike to start rolling just because I’m resting my foot on a pedal while standing still. I do that a lot at traffic lights. It takes almost half a pedal-turn for the motor to kick in, and about a second to shut power off when you stop pedaling. Power is cut instantly when you squeeze a brake lever, front or rear. The Aurora always turns on with pedal-assist at level one (of five). Assist level is controlled by the two outer buttons, and they work very well with a light press. No extra pressure or wiggling needed. If you want to pedal without any assistance, you simply switch power off to kill the electricals.
What’s it like to ride? It’s a kick. It feels odd to have the bike magically speed up faster than your own effort allows. As you go up in pedal-assist level, it accelerates faster and reaches higher speeds with the same lack of pedal effort. I suspect that acceleration rate is computer-controlled, because acceleration is never as muscular as the motor is physically capable of, say, by simply wiring the battery straight to the motor. Safety feature, I’m sure. This isn’t an electric motorcycle, and thanks to the smooth operation, there are few unwelcome surprises.
Should you tire of pedaling, a twist of the throttle collar on the left handgrip will feed power to the motor while you sit in your dull stupor. The motor drives only the front sprocket, so you can pedal, not pedal, or backpedal at any time. It would appear that the throttle feeds slightly less power at maximum than the pedal-assist system does at its max. This slight lack only comes into play when facing a stiff headwind or steep hill, and I don’t consider it to be of any real consequence. Want to get that extra one or maybe two MPH? Pedal, slug! You don’t have to actually work, mind you – just rotate the crank as lethargically as you like so the sensors think you’re trying to help.
How fast will it go? 20 MPH. That’s the federally mandated limit for motorized bicycles. You can bump this to 24 if you want to raise a finger to The Man, by resetting the controller, instructions supplied. Naturally, that’s officially for “off-road use only”. The max speed limit is also adjustable downward. I may well bump the max speed up, even though I want to maximize range by limiting speed so I’m not pushing all that air. The reason? When you have that rarity known as a strong tailwind, standing on the gas has very little energy penalty. It’s easy to reach 20 MPH and, as soon as you do, the controller shuts off power to keep you there. Then it turns on again as speed sags. Bummer. The tailwind is free energy and speed, so my hope is to be able to get out of it what I can and experience less of the depressing sag as power cuts out. I’m still not used to that characteristic – even now, every time the controller cuts power at 20 MPH, I still have the momentary, alarming assumption that something electrical must have just failed. Not relaxing. I’ll get over it eventually.
Speed costs juice, and electrical juice is in limited supply when you’re talking about longer distances to cover, particularly when 500 watts is on tap. That’s where e-bikes will trip you up, I quickly found. The siren call of easily-available speed is hard to ignore after you’ve spent years wheezing away at walking speeds, cursing every hill. Suddenly, you’re a high-speed junkie, going longer distances at much higher speeds than mortal man has ever achieved. You just can’t resist the urge to get to the store fast. As fast as possible! Yeee-hah! Then, if the trip distance is long enough, you’ll find yourself pedaling a 65-pound bar of steel and lithium back home, solo. Some simple, adult self-control is needed here, and I’m still looking for mine. I know it’s here somewhere. Hey, at least now I’m using the pedals instead of just the throttle. Usually. You gotta give me that.
How far can it go on one charge, the 500-watt, 48-volt Aurora? With its 10Ah pack, the published maximums are 20 miles on throttle alone, or 40 miles if you pedal in an earnest way. Same ratings as the 250-watt 36-volt standard model. With a new pack at least, those ratings are bunk. Mind you, I haven’t had much time or decent weather to play with it, but I’m currently at 35 miles on my second charge, riding like a pedaling-challenged speed freak, and the battery indicator is hinting that I may possibly tack on another third to that before the pack goes dead. True, that’s in flatland Illinois, but I’ve been particularly fast and lazy up to this point. Speed junkie. Lazy speed junkie. And it’s been windy. This is very promising for when the terrain gets more hostile out west.
I have yet to discover exactly how the display’s battery level indicator correlates to real-world energy reserve in use, since I haven’t ridden the battery flat yet. It appears to simply measure voltage, which is as good a way as any without getting into elaborate and expensive computerized analyzation. Sticking to low pedal-assist settings and taking it easy on speed, the reserve meter is very accurate. If you spend much time at full-honk, using lots of power, you’ll eventually notice that the meter has dived much lower, and you think to yourself that this thing is never going to make twenty miles. So you back off, and in a minute or two, the meter returns to its higher reading. This is characteristic of how all batteries behave. Voltage dives when you yank out a lot of power, but give the battery a chance to settle itself back out internally, and voltage rises again. What I’m getting at is that, used gently, the Aurora’s battery indicator is an accurate measure of reserve. Used mercilessly, I’ll probably be able to go further than the gauge says I will, because only the voltage is sagging, not the wattage capacity. All I have to do to get a truer picture of how the battery is really doing is to slow down and admire the scenery for a few minutes, to give the battery a chance to do its thing and show that on the meter. Pshaa, like I will ever actually do that!
For those whose eyes glaze over from technical stuff, skip this paragraph and the next. Various bikes advertise how they use various motor wattages and different voltage levels. What does it all mean? And what’s “better”? I’m neither an electrical guy, nor am I very knowledgeable about electrical stuff, but that won’t stop me from dumping my ignorance on you. Watts are watts. Given similar motor efficiencies, a 500-watt motor has nearly twice as much forward thrust on tap as a 250-watt motor. Use that 500 watts a lot, and the battery will drain at least twice as fast. But timidly restraining oneself to not use that extra 250 watts will extend range almost back to that of the standard 250-watt motor. That’s my fervent hope, anyway. My more powerful Aurora will be unlikely to equal that of the standard variant because I’ll be tapping into that extra power reserve every time I dig into a bad hill, but as long as I restrain myself on the flats, the range penalty should be minimal.
The main benefit of bumping the system up from 36 volts to 48 (in my view) is both a little more power and greater efficiency. Carmakers began going from 6-volt systems to 12-volt in the 1950s because of the need for more powerful starters for the bigger engines, and more electrical accessories. Main wire gauges were already huge, and upsizing further was expensive and added a ton of weight. Refusing to upsize the wiring would increase resistance, preventing the larger starter from getting the wattage it needed because the extra draw would be lost in the wiring by converting it to heat. That’s how a toaster works – the “heating elements” that glow red are nothing but wires that are way too small to carry the power being forced through them. Doubling voltage allowed pushing twice the electrical “pressure” through the same size of wire. They didn’t actually need fully twice as much power, so the main cabling in 1960s and later cars is markedly smaller than 1940s cars, decreasing wire harness costs. More recently, there has even sporadic talk of the need to double voltage again to 24. Evelo’s 500-watt motor works through a given set of wires, quite possibly the same wires used on the 250-watter. Bumping voltage up to 48 is a sign that simply plopping a 500-watt motor into their 36-volt system creates too much loss to resistance in the existing wireset. That cuts efficiency and range at higher loads as the wires heat up. So the choice is to increase voltage or install heavier wiring. Real world, what I assume the manufacturer did was to keep the existing wiring, bump voltage up, and just live with a level of resistance that may crimp the 500-watt a bit, but not enough to make the motor upgrade useless or trash efficiency. The bike’s electrical efficiency (and range) at lower throttle settings may actually be better than standard (because of the use of higher voltage through the same size wires). I’d expect that its efficiency at high throttle settings is okay but far from optimal. If this blind guessing were true, it’d be one more reason to take it easy when going for maximum range. End of speculation.
I should mention that if you’re expecting the e-bike to step out smartly and top out at 20 in a few seconds, it ain’t gonna happen. Ditto for climbing right up there against a headwind, or up a grade. It’s a slow increase, and top speed drops. You can watch the display momentarily topping 800 watts on the 500-watt motor, but this is not what you’d call a kick in the pants. Oh, you can certainly feel the torque surge in at assist level 5 when you’re trying to cross the highway with traffic coming up. It’s a comforting mini-rush. But popping wheelies and breaking the sound barrier ain’t gonna happen. It’s a bicycle with a small electric motor strapped on. It’s there to help you, Mr/Ms Prime Energy Source.
One of the true beauties of this particular bike is the NuVinci 360 gearhub in the rear wheel assembly. I’ve already described its operational advantages in my previous article, and it lives up to its billing in practice. There is no 1st gear or 2nd – it’s a smooth glide up the numerical ratios until you hit its mechanical limit. It’s controlled by a twist collar on the right handlebar, which can be turned either way at any time. There’s no need to start or stop doing anything in order to change the drive ratio. There is no shift routine. To indicate where you are on the scale, a small graphic of a bike going along a surface warps somewhere between a bike climbing a hill, or going along a flat. Clever. The hill indicates that a lower gear is being used. Numerical designations would defeat the point that there are no fixed gear ratios.
If you’ve ever used derailleur shifters or a conventional multi-speed gearhub or, worse, a two-speed coaster hub where you have to backpedal to change gears, the NuVinci 360 is a freeing revelation. Me likee. It requires no finesse, is nearly imperious to the elements, and is as reliable as a hammer. You just turn the collar and check how steep a slope the little biker is on. My hub sample initially produced a quiet, ringing, scraping noise in the lower ranges. Didn’t affect function, and now with 67 miles on it, I very rarely hear it. Also in that time, the collar occasionally downshifted fine most of the way and then wouldn’t go any further, but just two occurrences within that mileage doesn’t concern me, and others have confirmed that it happens every great now and then. You just move something a bit to let it do its thing, and try again if you must insist. Functionally, it’s not much of an issue since the very lowest gears are rarely used – the bike’s power is such that on the flat, you tend to prefer to use the motor’s torque in a gear higher than the bottommost ratio anyway. Such a sporadic quirk makes little difference on an e-bike like this.
I don’t know what the highest and lowest ratios are that the NuVinci provides, but I can say is that, as installed in the stock Aurora, its range is fully adequate to cover all needs for its intended market. The width of its range does not match my 18-speed Raleigh mountain bike, where you can pedal furiously and barely be rolling. I won’t know about the top end for quite some time, as that will require a paved downhill such as I encountered in Wickenburg, Arizona. Because the Aurora’s speed limiter cuts all power off at 20 MPH, an aggressive slope is needed for me to overcome that and increase speed all by myself. By pure feel, the NuVinci’s top end may not quite match the Raleigh’s. I may downsize the front sprocket a little in order to give both myself and the motor a little more leverage going up the nasties. That may trim top speed a tad, and maybe not.
Let me slop in a dollop more of minutia. Electric bike reviewers tend not to like mid-drives like the Evelo, and I ran across this while I was researching e-bikes, trying to decide what to get. One thing they don’t like is that maintaining a high pedaling cadence is more difficult at higher road speeds. Watch the athletes competing in a bike race. They are pedaling at a fast rate, maybe 70-90 crank revolutions per minute, or more if they are really going for it. If you can do that on a standard touring bike, you can stay in the lower gears, where your power and leverage are. Road racers tend to take great pride in their cadence rate, great pride. Between the computer and the internal gearing of the Evelo’s drivetrain, you can maintain a high cadence by turning up the wick on power assist levels, and staying in the lower gears. Churn away!
Here’s the deal. Ramping up the pedal-assist level virtually takes over below 10 or so MPH, allowing you to pedal like a dervish if you like. What happens at higher speeds kinda depends on the wind or grade. Since the Aurora’s Tonaro mid-drive is linked to the same pedals you are, then back in Engineering at design time, a line has to be drawn somewhere about where the motor’s power curve should be, what the price point is and who’s most likely to be riding the bike, what their pedaling expectations will be, and thus lock in what reduction ratio the motor should use to share the pedal crank with the rider. This one is fully adaptable to energetic road cyclists – up to a point. From there on, it’s better suited to mortals.
What happens? At lower speeds, the motor is loafing and tops out at its maximum RPM, which corresponds to a pretty decent pedaling cadence (if that’s what you want). This continues at higher speeds if you have a good tailwind, but sooner or later, the motor will encounter enough resistance to slow down a bit under the load, and there goes your fast cadence. From what I can tell, the power curve of the motor is not near its maximum RPM, so should you insist, the extra speed will be much more up to you. The motor is not falling out of its power curve, but is actually falling into it. You can try to fake it by feeding in throttle to “take over” from the pedal-assist, but it will make no difference at higher speeds. Serious road cyclists hate the relative absence of maximum RPM power, because it feels like the bike has run out of steam under load, and now it’s mostly up to them to make any speed gain. Physics intrudes.
Point of fact, in general, electric motors develop maximum torque (twisting power) at zero RPM (stall speed). Engineering can configure the motor to develop maximum horsepower at a high RPM instead of mid-range, but such high-RPM motors also tend to be less efficient overall, eating up the wattage. On an e-bike that’s carrying its own limited power source, that’s generally not a good idea.
What particularly galls the testers is that the motor then kicks in strongly when you upshift to much taller gears, letting its torque really start to come into play. That’s where the power lives, at mid-RPM, not high. So they get wedged out of their fast spin and have to settle for more moderate cadences, the kind that you and I might prefer. As far as the drive system design is concerned, that’s what you asked for: high speed at a pedaling cadence best suited for the average bike rider, not a competitive quasi-athlete. Evelo’s market is too broad to engineer the Tonaro for numbers-oriented enthusiasts, like the higher models of the stratospherically-priced Optibike mid-drives. Evelo’s main buyers are just folks, the common clay of buyers who want to bike for fun, to commute, and do errands. They don’t spin much, or know or care what “cadence” is.
In contrast to Evelo’s mid-drive, wheel hub motors don’t give a damn what you’re doing or not doing with the pedals and gears, and they represent 90% or more of the market. You can spin the crank fast, or not, independently of the power source helper trying to directly rotate the rear wheel. That’s what these testers are used to, and they find the Evelo’s way of linking the motor to your pedal gearing choices to be objectionable, theoretical leverage advantages aside. They want to be able to spin that crank just as fast at 20 MPH as they do at 10, road racer-style. And that’s…okay. Trouble is, the mid-drive Evelo (and somewhat similar competitor Optima Pioneer Allroad) can’t do that and then suddenly adapt to me climbing aboard, wanting to loaf at a moderate cadence at the same 20 MPH, using the same pedal-assist system. They both aim for the same market, and share the same basic riding characteristics.
Then again, I’m not sure that an energetic, physically fit cyclist has any legitimate business reviewing a 65-pound commuter e-bike with sport road cycling techniques in mind. I’m not noticing any mountain bikers or commuters bragging about cadence, as they consider themselves lucky just to make some hills at all, any way they can. A few mountain bikers even prefer to brutally muscle their way along with single-speed hubs, apparently to atone for their sins, and plenty of them, must be. In all, the negative commenters don’t represent a significant portion of commuter/leisure e-bike buyers. As vocal and influential as enthusiasts may be, enthusiasm about a type of product does not equate to whose money is actually crossing the table for it. You can’t demand that an e-bike be engineered to cater to a different market than it already is. It’s one thing to say that a mid-drive won’t meet such niche cycling preferences, but another to say that, because of that, it’s a failed design in general. That’s a myopic condemnation, and I knew at once that this perceived cadence “fault” did not apply to my purposes, nor to the bulk of the bike’s intended buyers. Disregard – especially since one of the same reviewers was much more respectfully deferential on the same “problem” with the more revered-brand Optima’s new Pioneer. He had to, to avoid the slings and arrows of outrageous feedback.
I used to have a fairly high cadence, because I once rode a lot, and was young and fit. (Yes, they had bicycles then.) Now, I spend my time at no more than an occasional 60 revs and, as I see it, in actual use, Evelo’s Aurora is fab. You can spin if you like at lower speeds, but sooner or later, ordinary mortals are going to want to stop with the Speed Racer imitation, slow down the pedaling and step up the speed, letting the motor efficiently provide more of the thrust at a reasonable pedaling rate that they can sustain. For my more mundane purposes, the Aurora’s mid-drive is spot-on. Couldn’t be better. If you like to pretend you’re a Tour de France competitor, buy a hub-motor bike and have at it. Think I’ve expounded enough on that?
But will the power-optioned Aurora cut the mustard in the Great Southwest, hauling the goods up some pretty tough hills with loaded trailer in tow? Battery range aside, even 500 watts is not considered all that powerful these days. But that’s what the mid-drive is supposed to be all about, getting more from less when the going gets nasty. We’ll both have to wait for that answer. Don’t think of it as a frustrating delay. Appreciate the delight of anticipation. It can take notable grades, so the real question is how tough a hill can it take on its own, and then with me doing what I safely can to get the job done? I do have operational legs, last time I looked. My goal is simply to cut the Wheeze Factor down to a manageable level.
I should also mention the control layout, because it’s reversed, in the European milieu. Having ridden motorcycles in the past, my psyche is trained to twist the throttle with the right hand and gently squeeze the front brake there, firmly squeeze the clutch with the left, and use the right foot for the rear brake pedal. I’d even reversed the Raleigh’s brake levers to avoid a surprise in making an instinctively firm left squeeze of the front brakes.
The Aurora’s layout gave me pause, but although it’s funky, it proved different enough in execution to not screw me up. Its twist collars feel differently enough from full twist grips to allow mental retraining from the motorcycle camp. Rolling back the right collar upshifts the NuVinci and increases speed. The rear brake handle is there, and I’m getting used to using it as the primary brake. Rolling back the left collar engages the direct-drive throttle to increase motor speed, and the front brake handle lives there. (Squeeze the front brake too strongly, and you lock up the front wheel – a bad thing on a bike.)
Getting used to the “reversed” brake levers is a significant thing, because the Aurora wears a very effective disc brake on each wheel. Squeeze pressure is measurably less than the old standard calipers pinching the wheel rims, to get the same deceleration. I’m not dead sure I’ll want to service them, but I do prefer them. They are crisp, smooth, and effective. Bike disc brakes have several claimed performance superiorities over the rim squeezers, but where I ride the most, I’ll likely never need them. (Braking in the wet, and long downhills needing prolonged braking.)
As predicted, the Aurora’s Velo seat started giving me problems after an 8-mile ride, even though I must admit that it’s a pretty decent, usable seat for a normal person. Not too hard, not too soft. The rear of the seat visually appears to sport springs underneath, but they aren’t springs. I’m not sure what they are, but bottom line, they do not give under pressure. My hornless Spiderflex seat was the first item to be swapped in.
The Aurora’s flat, mountain bike-style handlebars became the other issue. The Ergon mini-grips (shorter to allow room for the control collars) are flat-out excellent, delaying a lot of the numbness caused by the lean-forward pedaling position. For me though, the bars still need to be replaced with cruiser-style handlebars and a stem extension ASAP, making it more like Evelo’s Luna model. With that done, long distances should be limited only by getting my butt used to being on a bike seat for hours, and that is not limited by age or physical impairments, hallelujah.
Actually riding the Aurora is pretty much a no-brainer. There’s nothing to get used to. Just climb aboard, turn it on, and start pedaling. It will by default kick in a minimal assist after less than half a pedal stroke, and if you’re in a place where space or soft ground makes that clumsy, you can just goose the throttle to get yourself rolling. If you’ve left the NuVinci in high gear, just keep doing whatever you’re doing and twist its collar for a better ratio to get you rolling easier. The motor will pull no matter what, but shifting to a ratio that is better for pedaling is also better for the motor. And because you and the motor are effectively linked together, there’s no need to try to guess what gear you’re supposed to be in at any given time. You should be in whatever gear feels right for you, just like a regular bike. The motor will go along with whatever you choose. Changing assist levels is easy and instantaneous, so between that and the stepless gearhub, life is very, very good.
Stay tuned for The Evelo Aurora Arrives, Part II. Hard to believe, but there’s plenty more to jabber about on this e-bike!