Will all e-bikes be front hub motor in future?

E-bikes are still a technology in it's infancy with nothing like a consensus on design. Models in the first decade to about 2001 tended towards either drive through the chain or drive directly onto a tyre via an abrasive roller, but as time went on the hub motor in either wheel increasingly became the most popular.

 

From 2001 to 2006 Giant were the mainstay of drive through chain with the Panasonic unit, but when they discontinued that and adopted the front hub motor Suede it seemed the front or rear wheel hub motor would dominate. Since then Giant have firmly locked themselves into front wheel hub motors with the New Twist 1 and 2 models and now the Freedom and Express models.

 

Over a year later we saw a revival of the drive through chain Panasonic unit with increasing numbers of bike manufacturers adopting it in 2008, totalling ten at the last count, though the existing e-bike manufacturers have avoided adopting that approach, staying with hub motors.

 

However, things seem to be on the move again. Two of those adopting the Panasonic unit recently have now adopted front wheel hub motors on their latest models, Kalkhoff with both the Agattu F and Jubilee models, and Gazelle with their Innergy model. Since the front hub motor in those new Kalkhoff models is from Panasonic, the former chain drive stalwart, we might expect it to appear in other makes once the two year exclusive deal with Kalkhoff has expired.

 

Now Wisper, formerly tightly wedded to rear hub motors is introducing a new 906 model with a front wheel hub motor to run in parallel, and new models from Cytronex and the Raleigh/Powabyke partnership are front hub motor. Powacycle, formerly also wedded to rear hub motors, have equipped their new high end multi-battery bike with a front hub motor.

 

Factor in that the variety of available types of multi sprocket freewheels that are needed for rear hub motors are rapidly reducing and the trend seems inexorably in one direction over the years, towards the front wheel hub motor. Maybe we are on the home straight towards a consensus on e-bike design in the way that the motor and motor cycle industries have achieved with their main model types.

.

Edited January 28, 200917 yr by flecc

Besides Panasonic have other plans for the front wheel.

 

Like, they're gonna make them square?

 

hehehehe.

 

Vikki.

I didn't think they would Scott, just musing about long term trends and the one way direction they are tending to take. A bit like front wheel drive came from a minimal start with Citroen and gradually dominated the bulk of the car market over a number of decades.

 

Doubtless other European manufacturers in Germany and Holland will be interested in the Panasonic hub motor at such time as it may become more widely available for the same reason that Derby Cycles wanted it.

 

If it doesn't become available there are other new front hub motor options of course, as Giant, Gazelle, and now Wisper have shown.

.

Hi Flecc

 

 

 

Besides Panasonic have other plans for the front wheel.

 

All the best

 

Scott

 

Oooh tease ! What could they possible do with the front wheel?Add a dynamo? Put those little bead things on the spokes to make the wheel look pretty?Selloptape a business card to the forks so it clips the spokes and makes a " brrrrrrrrrrrrrrrrrrr " noise as it rotates?Remove the wheel completely and have the first electrically assisted unicycle?

Like, they're gonna make them square?

 

hehehehe.

 

Vikki.

 

I think Scott may be referring to Panasonic's new regenerating front hub brake which charges the battery every time it's used.

Edited January 28, 200917 yr by flecc

I think Scott may be referring to Panasonic's new regenerating front hub brake which charges the battery every time it's used. This particular design precludes the use of a front hub motor.

.

Something else to go wrong then, will it be efficient enough to be worth the extra investment?

I think front hub motors will succeed for the same reason front wheel drive has - cost. Most of the bike then remains standard allowing the most cost efficient components to be used, when the cost of batteries come down then pedelecs could easily become mainstream. Rear hubs and chain drive will remain expensive luxuries for the discerning (or picky) cyclist.

 

I like rear wheel drive but if it becomes a more expensive option then I'd probably get a front motor.

This is the link to the re-generaive ebike from Panasonic. I remembered reading about this last summer.

Panasonic presents electric bike recharging its battery via the braking system

This site has some further technical detail on the system.

.

My ideas are better:mad:

To me it wouldn't matter if ebikes were front, middle or rear powered...the ability to easily maintain 15-20 mph,a range from 50 miles upwards for the battery,battery life of 3-5 years and battery price upto £300....hmmmmmm it looks like the biggest bugbear (is that spelt correctly?) is the good old bbbbbbbbbbbbb battery......maybe with the current Kalkhoffs and Wispers about, time will prove that my biggest concern is getting better...but i have noticed a few failures on the forum in this department recently......

In my opinion, a front hub motor gives the advantages of all wheel drive i.e. pedal powered rear wheel and motor powered front wheel. This can be useful when going off road due to the extra traction combined with subtle use of throttle contol.

I have been quite surprised at how well my Torq goes of road, even on Schwlabe M+s.

 

J:) hn

It's main benefit though must be total and unhindered ultimate gear selection and choice to whatever your heart desires.

(From a road only perspective, none of this muddy business for me!)

 

Do the pro's and con's for the front powered wheel outweigh those for the rear powered wheel? I'd have thought that if you were happy with the gearing on your bike then it would make sense to have it in the rear as in the front the extra mass will interfere with the steering (easier to turn a light wheel etc.)?

 

\muses

This is the link to the re-generaive ebike from Panasonic. I remembered reading about this last summer.

Panasonic presents electric bike recharging its battery via the braking system

It doesn't work unless you are going under 15mph downhill or gentle slow braking, so it's suited to sedate riders only then?

It doesn't work unless you are going under 15mph downhill or gentle slow braking, so it's suited to sedate riders only then?

 

It's only for the home market at present, and Japanese law on e-bikes is very restrictive. I'd guess it's quite low powered too, judging by the small motor size and the fact that it integrates a friction brake as well.

 

Odd system, one brake lever gives light braking, two levers medium braking and squeezing hard on the levers gives the friction brake. Those first two levels are switched constants it seems.

.

(From a road only perspective, none of this muddy business for me!)

 

Do the pro's and con's for the front powered wheel outweigh those for the rear powered wheel? I'd have thought that if you were happy with the gearing on your bike then it would make sense to have it in the rear as in the front the extra mass will interfere with the steering (easier to turn a light wheel etc.)?

 

\muses

 

 

I agree - but a high percentage of rear-wheel-motor owners, (including myself), do appear to be dissatisfied with the gearing options available to them with this method.

I agree - but a high percentage of rear-wheel-motor owners, (including myself), do appear to be dissatisfied with the gearing options available to them with this method.

Me too, but that's more to do with the lack of changeable chainrings than the three missing gears at the back.

Oh! Not square ones then - I'm disappointed

 

Vikki.

Opinion: I think this is a very interesting question.

 

As e-bikes evolve, there seems to be two branches of design which I think are based on different historical paradigms.

 

Motorcycle paradigm: Motorbikes have been around for some time now, and have a fairly predictable form-factor, one school e-bike design seems to be following this concept.

 

Basically the motorcycle paradigm consists of a motor which is run at the optimum rpm for its particular power curve, and a transmission that converts this into varying wheel speeds as desired.

 

E-bikes with crank drives fit this model as they are designed so that the rider quickly reaches a pedaling cadence that allows for maximum power output from the motor, and encourages the rider to maintain that cadence to continue getting the maximum amount of assistance. I have had several years riding experience in this mode, and frankly have the feeling that the rider is sometimes serving the motor (and controller) as much as the motor is serving the rider.

 

Perhaps the best fit is for the rider who, in their heart of hearts would actually prefer a moped, but out of guilt or desire to get 'some' exercise prefers an e-bike. (flame war predicted…)

 

The second paradigm is the bicycle paradigm. In my opinion, one of the joys of bicycle riding has always been the freedom and variability of it. You can decide to spin the cranks one day to help your circulation or leg muscles, and then on another day, you can decide to ride in higher gears and really push yourself.

 

I think the hub motor systems really fit the bicycle paradigm better, as the power source is separated from the drive train and gearing. Hub motors are more like having an invisible helper - remember feeling really great and then realizing you were cycling with a tailwind?

 

In spite of all the engineering arguments about motors, batteries, and manufacturing efficiency, I think cycling is more about freedom and enjoyment rather than physics or technology.

 

Extraenergy.org has just set their criteria for a new testing methodology in 2009: New Test Launches in Early 2009 - ExtraEnergy.org After many years of e-bike testing experience they make the following statement: "the basis of the test is the real experience of the rider and performed output. In the end what matters is whether the bike is fun to ride or not. No machine or test bench can provide these results"

 

I therefore think that the hub motor is closer to the natural bicycle paradigm in that it gives more freedom back to the rider. Hub motor designs may also have a psychological factor as most "non-geeks" feel more comfortable riding a bike that has a more traditional look and feel. As for front vs rear hub motors, I think the front motor is just a better fit for most bicycle frames as it allows a rear battery and better weight balance.

 

I think the bicycle paradigm is perhaps better for the person who used to do more riding in the past, and is now either older, less fit, or has a longer or more difficult commute. In this situation, the bike just makes up for the rider’s shortfall, making the them feel younger, stronger or fitter, while still giving them a true bicycling experience.

 

Of course, it always depend on how steep the hills 'really' are...

People at work have asked me why I don't get a moped. Simple, it puts me on the road and wouldn't be much better than Bikey. I spend 90% of my time on cycleways and shared pavements for my journey. Safety thing I guess, for me.

 

There is another parameter that goes with front or rear wheel drive.

 

With rear wheel nearly all the riders weight is on the rear wheel so the driven wheel gets more traction. I noticed that on an icy day on my old front wheel drive bike. On ice the front wheel would spin briefly before biting (I went very carefully after that as I realised there was black ice about).

 

With front wheel drive the motor pulls the bike evenly regardless of which direction the front wheel is pointing. Rear wheel would see a substantial current increase if the front wheel was turned at a sharpish angle during pulling away (since the bike is not tilted at low speed). Of course, the motor isn't doing all the work but they kick in quick enough after a turn of the crank or two. Very minor of course since how often due you not pull away in a straight line

 

Just some idle thoughts. I'm quite happy with front or rear wheel drive.

 

Vikki.

 

E-bikes with crank drives fit this model as they are designed so that the rider quickly reaches a pedaling cadence that allows for maximum power output from the motor, and encourages the rider to maintain that cadence to continue getting the maximum amount of assistance. I have had several years riding experience in this mode, and frankly have the feeling that the rider is sometimes serving the motor (and controller) as much as the motor is serving the rider.

 

Although true, this is mainly due to Japanese law and it's ill effect on the design of their bikes. It's not true of the Taiwanese Cyclone system for example, which has it's motor throttle controlled like a hub motor.

 

 

I think the hub motor systems really fit the bicycle paradigm better, as the power source is separated from the drive train and gearing. Hub motors are more like having an invisible helper - remember feeling really great and then realizing you were cycling with a tailwind?

 

The flaw in this is the drag that almost all internally geared designs have on the overrun, as in pedalling without power. Only Tongxin with their Nano motor have overcome this with true free running and light weight. All the others have the cycling experience spoilt to some extent.

 

In the end what matters is whether the bike is fun to ride or not. No machine or test bench can provide these results"

 

Completely agreed, the personal experience is paramount.

 

As for front vs rear hub motors, I think the front motor is just a better fit for most bicycle frames as it allows a rear battery and better weight balance.

 

Weight balance on two wheelers is very unlike that on cars etc, and front/rear balance is not necessarily important. The bicycle and rider combination generally has a huge rearward weight bias anyway. I prefer a rear weight bias and converted my my front hub motor bike to rear motor to improve it's handling and comfort. Likewise a low centre of gravity far from being important in two wheelers is often undesirable.

 

I think the bicycle paradigm is perhaps better for the person who used to do more riding in the past, and is now either older, less fit, or has a longer or more difficult commute. In this situation, the bike just makes up for the rider’s shortfall, making the them feel younger, stronger or fitter, while still giving them a true bicycling experience.

 

Yes, I fully agree with this, there's a clear separation from the "moped replacement" market many designs occupy.

 

 

Of course, it always depend on how steep the hills 'really' are...

 

And this is the crunch, legal hub motors performing increasingly poorly on inclines over 10%, especially with heavy riders. Then the crank drive can become the only sensible option.

 

My conclusion is that a crank drive adding to the rider effort and designed with the cyclist in mind could still be the best option for an optimum cycling experience, but so far it doesn't exist.

.