The Advantages Of A Lightweight eBike
There are numerous claims from e-bike manufacturers to have produced the lightest e-bike in the world and reports of new e-bike tech are constantly promising a golden future of ever lighter e-bikes. But what’s the reality of lightweight e-bikes today?
As well as looking at some of the class leading examples of lightweight e-bikes it’s also worth asking just why there is a demand for lightweight e-bikes (and there most certainly is) and why you might or might not need one. After all, many of today’s e-bike motors are so powerful they can power just about any weight of bike up to the legally assisted limit (usually 20mph or 15.5mph depending which country and/or state you live in).
Why Might You Want a Lightweight E-bike
Handling on and Off the Bike
Fashion appeal is no doubt part of the answer; lightweight e-bikes simply look sleeker and, with the current state of small motors and in-frame batteries, may barely resemble electric bikes at all. Those who want to appear fast and sporty on a bike (but want some extra assistance) could well be attracted to lightweight e-bikes.
But there are numerous practical reasons why lightweight e-bikes might make sense for you too.
Light e-bikes feel sportier to ride and handle and certainly are easier to ride up hills if you like to use lower power levels or are exceeding the electric assistance speed limit.
Regularly carrying a very heavy e-bike can be at best a pain – if you have occasional big step to lift it over – and at worst a real problem – for example if you need to carry it up a flight of stairs into your flat. For regular carrying up stairs you should really aim to get the weight of the bike as near 33lbs / 15kg as possible and ideally a few lbs/kg below that (though if you want a bike with practical features like mudguards, rack and built in lights that might not be feasible and 40lbs / 18kg is a more realistic target). Ampler e-bikes are both lightweight and well-equipped for city use and Specialized are also serious competitors in this area.
If you want to aim for much below 33lbs / 15kg a minimally equipped bike, perhaps even a single speed might be the only feasible option. For example COBOC’s ONE eCycle F1 has a claimed weight of 24lbs / 10.8kg.
More Range, Longer Battery Life And Easier Cycling Without Power
Keeping the total weight carried as low as possible – both the bike weight and the human and cargo weight – will help both extend your battery range and its life as it will need charging less often and charging and recharging are one of the main causes of battery degradation.
That’s not to say a light e-bike needs to have a small battery (though most very light e-bikes do). The lightest pared-back version of the newly launched Specialized Turbo Vado SL have over 330Wh of battery which is a decent size and it also has a range extender system meaning you can plug extra batteries in – and it claims to weigh 33lbs / 14.9kg. For an e-bike with a mid-drive motor, 10 derailleur gears, integrated headshock and a decent size battery that’s extremely impressive.
Here’s a video showing the technology that has gone into making the bike what EBR considers best-in-class:
If you should happen to run out of battery power a lightweight e-bike with a freewheeling motor (easy to pedal without power) could be a lifesaver and allow you to get home with calling for backup too.
Lightweight eFolders
Folding e-bikes are undoubtedly the design of e-bike where weight is most critical of all. After all, the idea of a folder is that it can be carried (though there ways around that for heavier folders, but we’ll come to that shortly). The headline grabbing world’s lightest e-folder with a corroborated weight that EBR is aware of is the Hummingbird Electric from the UK.
If it’s simply light weight that’s needed the Hummingbird will be extremely difficult to beat but it has its limitations; it’s not the smallest folded package, it’s has only a single gear and features a small 158Wh battery with a relatively inefficient direct drive motor.
If it’s a powerful efficient motor and good sized battery you are after Tern’s Vektron range are best-in-class Bosch-powered folders. Of course, a powerful motor and a biggish battery come with a weight penalty, so Tern folders are only really light in the sense they will do all things that many larger non-folding bikes will do – and more, including attaching a child seat.
The weight means they really be carried any distance but they are designed to roll easily along station concourses and the like. Here’s more detail on the great flexibility and many functions offered by this bike range:
Another ‘folder roller’ – somewhat lighter than the Tern – is the uniquely designed and very sporty Gocycle GXweighing in at 41lbs / 18.8kg.
Undoubtedly at the head of the pack in terms of quick compact fold is the Brompton. At nearly 40lbs / 18kg Brompton’s own electric version is a little on the heavy side – EBR’s own favourite is the retrofit Cytronex Brompton kit which we reviewed here. The kit adds around 7lbs / 3.2kg to a Brompton – unassisted Brompton bikes start at around 24lbs / 11kg (for the more expensive titanium Superlight versions) so at little over 31lbs / 14kg this combination has to be one of the lightest and best folders out there.
Speed Up Hills – eRoad Bikes
Professional road racers riding non-electric bikes obsess over weight as it is one factor that can help them climb hills just that bit quicker than rivals – and of course this view also applies to competitive amateur club riders.
Put simply, cycling uphill means working against gravity, so the less weight you have to get up the hill (all other factors like power rider output, wind and rider weight being equal) the quicker you will be.
Bike weights in the world of racing have come down and down over the years, so much so that the sport’s governing body, the UCI, has set a weight minimum limit of 15lbs / 6.8kg (for non-electric bikes!).
Electric road bikes are by their nature light weight and are becoming increasingly accepted by a once sceptical road biking fraternity. Seeing e-road bikes ridden for fitness alongside regular road bikes on group rides is increasingly common. Many models billing themselves as two bikes in one – an e-bike and a regular bike as they are designed to be ridden above the assistance cut out limit as easily as possible. There is even a removable motor system used on many e-road bikes from German firm Fazua. That design means you literally do have two bikes in one; a powered and an unpowered one.
As e-road bikes use many road bike components that are already shorn of weight they only need a lightweight motor system adding to be some of the lightest e-bikes out there. The Ebikemotion (Mahle) rear hub motor system has been added to a range of bikes by UK-based Ribble who claim their lightest build is around 24lbs / 11kg. However, Switzerland’s Wilier claim to have gotten down to 23lbs / 10.5kg with their Cento10 Hybrid model.
The smoothest possible transition from electric assistance to non-electric riding are what e-road bikes seek to achieve so they can be used as genuine sports machines and fitness tools.
Cargo and Weight
Electric cargo bike are probably the least likely candidates for a weight saving approach – after all large powerful motors and incredibly strong heavy-duty frames are what is required when adding large carrying platforms, boxes or racks and of course that means quite a lot of extra weight.
But even then it makes sense to keep the bike as light as possible if only to make it pleasanter to ride when unladen and easier to manhandle and maintain when you aren’t on it.
One company that has taken this approach to heart is the Danish firm Larry vs Harry who produce the Bullitt cargo bike (which also comes as an electric option). Starting at around 55lbs / 25kg, little more than the average weight of a well-equipped hybrid e-bike, the bike is designed to handle loads on it’s front platform of up to 220lbs/ 100kg. No mean feat.
And if you thought speed and nimble handling (helped by having a light bike) weren’t important to serious cargo bike riders think again…
The $ting in the Tail – Downsides
Very light e-bikes aren’t of course the magic bullet for all biking needs. For a start they tend to be extremely pricey (though should hold their value well and prove a good investment). eMTBs are particularly hard machines to make light due to the need for suspension, large knobbly tyres and extremely strong frames that can take an off-road pounding.
41lbs /18.6kg appears to be current production line benchmark from LaPierre but costs 7,700 euros (around US$8800). For lighter carbon custom builds LaMere have a good reputation.
Possible practical downsides include the fact that some very light models dispense with battery cases and locks in order to save weight making the batteries non-removable from the bike.
If you after a real workhouse capable of taking big loads day after day and maybe even towing big loads by trailer, a bigger heavier more powerful mid-motor e-bike would of course be a better choice than the the lightest one you can find.
Despite these qualifications ever lighter e-bikes look set to remain one of the big quests and challenges for e-bike designers in years to come.
Stay tuned for more e-bike news and reviews and thanks for reading!
-Rich
Steve says
Terrific article makes excellent points about weigh.. For health reasons, I had to give up traditional cycling for e-biking. I wanted a bike that was light, handled as I was accustomed, required little maintenance, and that could be outfitted with racks or other accessories. At the time, I couldn’t find a production bike that met my requirements for a belt-drive, IGH, and 650b wheels, so I went the custom build route. In the end, it cost me not much more than a production bike but met my needs precisely. As EBR reports, there are more wonderful e-bikes on offer than ever. I’d like to suggest that people also consider custom builds as an option, especially for those who have health or other needs that aren’t accommodated yet by the major manufacturers
Peter says
As usual Rich overlooks the Brompton Electric which provides a powerful and elegant solution to the e-bike weight conundrum:: a liftable 13.7kg bike plus a separate 2.9kg luggage cum battery pack. Even together Brompton achieves the holy grail of a practical bike well below 17kg (not 18kg as stated here).
Yes, there are electric bike conversion kits and they will fit almost any bike, not just Bromptons. So if mentioning them, why not say so?
Lin B says
I love my 19lb Bike Friday pakiT folder with my OneMotor e-assist. Total weight including battery, motor, saddle, pedals, and accessories is under 24 lbs. Range 20+ miles in low assist. When you have to carry your bike up stairs and you’re not a large person, or you are elderly, weight matters most of all. The other advantages to my OneMotor system are that it’s 20 seconds to remove entirely and it can be used on my other bikes as well. I would never consider one of those heavy commercial e-bikes; they ride like a tank and if you run out of juice, good luck. Anything over 30 lbs is not going to be fun unless you’re using it for cargo/kid carrying.