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• Hub motors and mid-drive motors on electric bicycles – What’s that all about?

One of the most common questions that prospective buyers of electric bicycles have, is whether to ‘go mid-drive or hub drive’. Even people who don’t think to ask such a question are often bombarded by friends, sales people, manufacturers etc about which is better. What is it that they’re all on about and why is it even a thing? Do we really have to learn all that technical jargon to buy a good e-bike? Probably not, but knowing what your options are is important, particularly as you will not always be presented with all the options when you walk into a shop, unless it’s a true e-bike specialist, so make sure you get the chance to consider everything available to you before you make a decision. In most areas in NZ, this will mean visiting more than one shop.

Background Reading

Two years ago, we wrote an article about the benefits and drawbacks of the main motor placement options on electric bicycles, (re-published on our domain here) and now is a good time for a re-cap. The original article speaks in technical terms on the consequences of each motor placement option and therefore the pros and cons for the owner of the bike.  In this article, we will focus more on the non-technical side of it all. Well, I’ll try anyway, but you’ll still come across a lot of terms in here that are found in our Glossary or FAQ.

What are the options?

There are two general categories of electric bicycles for sale in NZ (and Australia, U.S. and many other places).

1 – “Hub-motor e-bikes with throttles” such as eZee Sprint, Magnum Metro and many more. These e-bikes are often from specialty e-bike companies as opposed to established bicycle manufacturers.

2 – “Mid-drive e-bikes”, eg e-bikes equipped with the motor drives by Bosch, such as Gepida, Moustache e-bikes, Riese and Muller and many more. European e-bikes are highly represented here, though there are plenty of factory generic options coming through as well.

It’s a lucky thing e-bikes are inanimate objects, as generalisations on these categories are unavoidable. And although there are always exceptions, the generalisations are definitely useful:

The hub motor category is more transport-oriented and excels in the nuts and bolts of transport – they go faster, have bigger batteries and are more affordable. The geometry and sizing is usually more ‘shareable’, fitting a variety of people. They almost always have throttles and cadence sensors, though the use of torque sensors in this category is growing. The bikes hold a bit more mass-market appeal, more likely to be built with function over form and don’t generally target the existing cyclist market.

The mid-drive category is almost synonymous with the european market, for reasons we will get into later. The choices in this category are more like non-electric bicycles in many ways, including aesthetics, geometry and sizing, ride feel and component choice. These are generally made by existing bicycle manufacturers who have a ‘bike first’ design philosophy, prioritising the non-powered nature of the vehicle over things like battery size, power, top speed etc. These bikes almost never have throttles and almost always have a torque sensor to help the bike know when you want power. They are generally slower, with most not giving assistance above 25kph. However, that is very quickly changing with more available at 32kph and 45kph.

Which option is the best?

You probably know I’m not going to answer that, they’re both great options and the beauty is that they are very different to one another. For an MTB rider that plans for both wheels to leave the ground at the same time, we will generally recommend a mid-drive. For an everyday rider who wants to do the occasional wine trail, the case for the hub drives is very strong, though plenty of people will prefer a mid-drive too.

I stick to the original article’s advice that you need to ask yourself (and your supplier) the following about any bike you’re considering.

1 -Do you feel confident when leaving the house on this e-bike, that you’ll have an enjoyable and safe ride that will make you want to use it next time you leave the house?

2 – Do you feel comfortable riding this electric bicycle?

3 – Can the electric bicycle go up hills with an amount of assistance sufficient to your needs/desires?

4 – Can someone service this electric bicycle for you, are spare parts available now and will spare batteries be available in 5 years?

What are the latest trends in the technology – why can’t one system have it all?

Since writing the original article, what’s changed in two years? Well, nothing that makes any of the original information inaccurate. However, there have been changes to what’s commonly for sale. In particular, there are many more hub motor e-bikes available with torque sensing systems, which was previously the domain of mid-drive e-bikes. And vice versa, there are many more mid-drive e-bikes available that can go faster than 25kph, previously the domain of the hub-motor bikes. This blurring of boundaries will make it even harder to draw any useful generalisations and therefore a little harder to decide in one sitting at your computer which bike to buy! However, deciding what to buy before you’ve ridden it never was a good idea. In reality these extra options mean it’s easier than ever to find an e-bike that you love, you may just find there’s a few more on your list to test ride than you first thought!

Bikes like the T4 torque sensing series of eZee bikes (Sprint Alfine T4 etc) are truly a ‘best of both worlds’ situation, with power in proportion to your pedalling achieving a smooth, natural ride, but still with the big batteries and heaps of power to go up any hill and higher top speeds.

Then we are also seeing the mid-drives offer higher speeds, with 32kph becoming an option for many brands, notably on most Shimano bikes since 2017 and some Bosch bikes from 2018. They still don’t have throttles and huge batteries, but for someone who wants to do most of the pedalling work but wants to go quicker than 25kph, this is also a ‘best of both worlds’ offering. It truly is exciting times for e-bike shoppers!

Why can’t one bike have it all and we can do away with these divisions? Some constraints certainly are artificial, such as a speed limit imposed in a different continent affecting what you can buy today, that’s a solvable problem. But other constraints are real – why do the e-bikes that feel most like a bike, not perform as well on the electric side? Because they’ve got a lower weight and space budget for robust motors and large batteries! Why do they cost more when they try to cover all bases? Because they’re having to spend more to accommodate competing interests. Evolving technology can cover some of these issues (eg lighter battery cells), but some are fundamental questions about what’s most important to you. Upright bikes are more comfortable but they’re less aerodynamic and are less suitable for swerving downhills on windy tracks – that’s a fact of physics and technology won’t change that. When riding on Tāmaki Drive shared path and getting buffeted by wind over a bridge, a heavy-set e-bike is your friend, but you won’t feel that way if you try to lift it onto a poorly designed car rack – technology won’t change that either (though a better car rack will).

There is a reason after all, why there is more than one bike to choose from! Take advantage of that fact and choose one you’ll love!

Further reading – Why do these different categories even exist?

The first thing to consider to understand all of this, is that NZ and Australia are small markets for bikes of any sort, due to small populations and a near-total decimation of livable cities in favour of car traffic. Now that the public is interested in buying e-bikes, we’re in the nice position of being able to choose from many different options that have been developed elsewhere for decades, so we get to skip straight to the state of the art without ever having put up with lead acid batteries, <10km battery range etc. All respect to the pioneers of e-bikes from the local early adopters, the NZ companies and the international companies that sold into NZ for the last 10 years, but the reality is that what is available to an NZ consumer right now is almost completely based on what has been popular elsewhere in the world and which of those happen to be pretty good matches for what’s appropriate to sell in NZ. And the availability of bikes elsewhere in the world has been influenced by user demand, technical constraints/achievements and the local regulatory conditions (ie what was legal and what wasn’t). The story of each market around the world over the last few decades is very interesting, but this has already gone on for too long. So we will look at Europe and the sector that I would call ‘the internationals’ as they have been the ones that kiwis have been buying from. The european market is based on what kinds of e-bikes the european bicycle companies were making for their own market. The ‘internationals’ is about what e-bike companies were making and attempting to sell all over the world, including NZ.

1 – The European experience and the birth of the mid-drives

The e-bike industry in Europe was an add-on to the bicycle industry on both the consumer and supplier side. That is to say that the consumers were generally people who wanted to keep doing things that were normal for them to do on a bicycle, but with electric assistance (Japan is the same in this regard). This meant the original market was for older people or anyone who needed motor assistance to do what other people were doing without motors. E-bikes were made therefore to be ridden alongside other established bicycle infrastructure and designed to behave like other bikes in speed, acceleration, weight etc. The buyers themselves were generally experienced in riding bicycles. The industry making the e-bikes were world experts in making non-electric bicycles and therefore offered all the same frame size options, geometry, slick aesthetics etc on their e-bikes as they did on their non-electric bikes. As a result, the bikes had small batteries and motors, weren’t intended to go very fast and not generally intended to do anything you wouldn’t do with a non-electric bike. The legislation forbid throttles and didn’t allow motor assistance past 25kph. Was everyone happy with this? Not at all, there were many pushes for faster e-bikes for more motor assistance and other obvious possibilities for an electric bicycle. This push generally came from hillier cities and places where bicycles and bicycle infrastructure was not as well established, as their needs were different. However, there was sufficient numbers of buyers in areas that were flatter and had existing riders, that a huge industry blossomed, with the Netherlands being the clear leader per capita and the Germans leading on absolute numbers. This market started with hub motors, but the market share is being overtaken by mid-drive motors, which do a better job of mimicking a non-electric bike. These are fantastic electric bicycles, we stock a range of them and recommend very highly that you try some and if it’s for you, you’ll be pleased as punch. However, we do not prescribe to the commonly espoused view that this is the ‘best’ category and that the only reason to buy from the hub motor category is for value for money reasons. That’s a narrow view of the market, based on an assumption that all e-bike owners want their e-bike to be just like their non-electric bicycle (only better) and generally is held by those who only sell European bikes or who are only reluctantly offering electric bikes, viewing them as some sort of compromise to a ‘real bicycle’. It appears as a majority viewpoint, simply because those who currently have an opinion on the matter and the privilege to air that opinion are those who write magazines, work for established bicycle manufacturers or who are in some way or another, part of the existing industry, which is based on non-electric bicycles. So what about the majority then, the people don’t use non-electric bicycles anymore? Or those who do use non-electric bicycles but want an electric bicycle to be different, to allow them to do things they wouldn’t dream of doing on a manual bike?

2 – The internationals and specialist e-bikes

The international e-bike companies have been selling e-bikes around the world for as long as you care to guess, for example eZee since 2001 to Europe, the US, NZ, South Africa, Australia etc. The experience of these companies was to worry less about what the regulations were in every single country and think more about what kind of e-bike they wanted to make and then see who would buy it. Their strength was not in non-electric bicycles and neither was their interest. The priorities became the nuts and bolts of movement – how big a hill can you climb, how far can you go, what speeds can the bike sustain? The geometry and componentry was chosen around that – what sort of frame shape can fit a big battery and still hold a lot of cargo that e-bike riders will want to carry around? What shape is comfortable, stable, safe and suits a lot of people. Why make 7 sizes when most e-bikes will get shared around the household anyway, why not make it more versatile, prioritising the vehicle over the biomechanical efficiency of a particular rider? It is well worth reading the interview transcript with Wai Won Ching, CEO of eZee on this subject.

The challenges for these companies was finding markets to sell into that could sustain an industry. The Europeans ignored any market that wasn’t big enough to pique their interest and for a reason – it’s hard to make ends meet in a small market and they have easier options. The e-bike specialists on the other hand, only existed to sell e-bikes, hard work or not.

The USA became a good market for the internationals because of the accommodating legislation (32kph and 500W was allowed in most states, throttles were allowed) and although the bike riding conditions were poor, the total population was big. The US consumer was also less likely to be impressed that a bike was made in Europe and more interested in the performance of the vehicle.

Probably what is missing most was a clear marketing message. “Designed in <insert country> for <insert country> conditions” is about as imaginative as it gets, compared to the marketing budget of bicycle brands that sell more units in one single shop in a Dutch city than all the e-bike shops in Auckland sell put together.

Where to from here for NZ?

Time of course will tell. The market will never be big in global terms, but it is getting big enough for us to be able to buy whatever we want, instead of what just happens to be imported into NZ. International companies are competing for market share here.

The next big step will be seeing what, if any, guidelines and regulations the NZTA assigns to electric bicycles. Government regulation is a double edged sword. The dangers of over regulating are obvious – if great bikes for our market are declared outside of regulation, the industry will shrink and so will consumers options. However, practical and clear guidelines from government will give the industry more certainty in what to invest and import.