Mid Drive for off trail and Hub Motor for flat commutes, true or false?

[nabs]

Seems like a lot of people are saying you should get a Mid-drive if you want to go off road or on hills, which seems to be true.

But is it actually true that hub motors are superior for commutes and flat rides?

Looking for a commuter bike. What type of motors do people here generally prefer for their commutes?

 

[Wicky]

An oldie hill climbing mule from 2014 but I'm still happy with it (KTM hub drive) on and off road and still going on strong - though discontinued a year or two ago

KTM eRace P 29 - Review

In all honesty, really we are fans of E-MTBs with centre-motors. With their low and central centre of gravity, they can be ridden on demanding trails as easily as their motor-free siblings. However, rear hub drives do have certain advantages. They work directly via the rear wheel, so have great...

ebike-mtb.com

Best get some test rides on a variety of different models / types.

 

[Woosh]

But is it actually true that hub motors are superior for commutes and flat rides?

yes. Compared to middle motors:
Hub motors don't get splashed by surface water, relieve stress and strain on your drivetrain and cheaper to buy.

 

[Nealh]

Pro's and con's on both accounts, my first emtb build was with the Oxydrive Bafang hub kit and I use to give it series stick. I would use it in similar conditions that EddiePJ also rides in and never regretted it, the hub kit gave me less hassle then my later BBS01 kit. The same hub is still in use now on my commute/town bike and has about 7k + mile son it now.
I currently don't have a working emtb kit bike but use my 700c Boardman with Aikema hub for all off road riding.


Like commuting there is little to choose , though hubs in the main give a more relaxed ride as you aren't so tied down to being in the correct gear. Mid drive kits have heat issues with controllers, grinding out /labouring the power is a sure way to blow the controller.

 

[Andy-Mat]

Seems like a lot of people are saying you should get a Mid-drive if you want to go off road or on hills, which seems to be true.

But is it actually true that hub motors are superior for commutes and flat rides?

Looking for a commuter bike. What type of motors do people here generally prefer for their commutes?

I actually think the opposite.
The reasons being that hub motors drive the wheel directly, and do not put any strain on the chain, giving it generally a longer life and often a "get you home" feature if the chain breaks and you can still pedal or use the throttle (if one is available), even though the chain is now in the saddle bag!
And I have done exactly that from a forest trip of some miles!
Getting started can be a bit fraught though on the bike I had at the time, and of course, no torque sensor is a must....
Mid motors use the chain as part of the drive mechanism, and may give a higher gearing for flat road use, reducing the "speed" needed from legs and feet pedaling, making the ride pleasanter!
But they are a total disaster if the chain breaks....WALKIES! Though a friend with a large car may be called to the rescue of course!
Furthermore, as all the motor and muscle effort goes through the same chain on most models, the chain is subject to far higher wear. Not forgetting the mid motor price and apparently they go wrong far more, the Bosch plastic gears of a few years ago being a prime example. Then there is the upkeep costs if there is a problem, as some of the firms have very "obtuse" mid motor guarantees......
Also, a mid motor needs to have a better way of powering the rear wheel to my mind, without a chain.
I have never owned a mid motor, though I have ridden them a few times. Their prices are often (IMHO) horrendous, for no positive effect that I can see!
If you can read German, look on the internet for just how many complaints are from Bosch powered bike owners in Germany, Austria and even Switzerland!!
Plus there are quite a few Bosch complaints here on Pedelec too!
I hope this helps you further.
Andy

 

[Audio2]

Just carry a chain repair tool.

 

[Andy-Mat]

Just carry a chain repair tool.

What if its very cold, what if its raining or snowing or hailing and you dressed for a warm ride, or lightning is hitting the trees around you, what if its very muddy, what if you simply have no time for it?
Simply no need to if you have a cheaper, more reliable Hub drive bike!
Just use the PAS to get home and do the job when you have the time and interest!
It will usually happen far less often on a hub bike as well!
Just "funning" with you as I don't think you thought that quip fully through!
And I believe anyway, a mid motor rider is better off with a new chain, of the correct length, oiled up and properly packed somewhere on the bike, probably lighter than the tools and far quicker to fit.
And if a chain broke, you probably need a new one anyway, generally speaking.
In over 8 years of e-biking, I only once had a chain break after a small accident on a big rock up in the forest.....I removed the chain completely and simply got going by peddling to activate the PAS system, luckily one with no torque sensor of course, though possibly a tie wrap might help to simulate torque , though I have never even seen such a sensor! Guessing only!
My present bike has a strong guard, welded to the bottom of the frame, to make that area of the chain ring far less likely to hit anything....Something new to me personally.
regards and have a great day!
Andy

 

[Benjahmin]

I'd say hub for commute. These motors are as near bullet proof as you'll get. Plus you don't have the motor dictating your cadence range. With a pas system, at the end of a long working day, you can ghost peddle home if you want.
I have 3 front hubs (none used for commutting 'cos I'm self employed) one with 7k miles plus on it. No issues, no broken spokes, no broken forks. That said if/when I convert again it will be a rear hub.

 

[Nealh]

Even though a hub bike is rideable to a degree with a broken chain, I always carry a spare and a breaker.

 

[Danidl]

I actually think the opposite.
The reasons being that hub motors drive the wheel directly, and do not put any strain on the chain, giving it generally a longer life and often a "get you home" feature if the chain breaks and you can still pedal or use the throttle (if one is available), even though the chain is now in the saddle bag!
And I have done exactly that from a forest trip of some miles!
Getting started can be a bit fraught though on the bike I had at the time, and of course, no torque sensor is a must....
Mid motors use the chain as part of the drive mechanism, and may give a higher gearing for flat road use, reducing the "speed" needed from legs and feet pedaling, making the ride pleasanter!
But they are a total disaster if the chain breaks....WALKIES! Though a friend with a large car may be called to the rescue of course!
Furthermore, as all the motor and muscle effort goes through the same chain on most models, the chain is subject to far higher wear. Not forgetting the mid motor price and apparently they go wrong far more, the Bosch plastic gears of a few years ago being a prime example. Then there is the upkeep costs if there is a problem, as some of the firms have very "obtuse" mid motor guarantees......
Also, a mid motor needs to have a better way of powering the rear wheel to my mind, without a chain.
I have never owned a mid motor, though I have ridden them a few times. Their prices are often (IMHO) horrendous, for no positive effect that I can see!
If you can read German, look on the internet for just how many complaints are from Bosch powered bike owners in Germany, Austria and even Switzerland!!
Plus there are quite a few Bosch complaints here on Pedelec too!
I hope this helps you further.
Andy

Your second last paragraph says it all.. . I have at this stage purchased three electric bikes, .. I am on my second and I purchased a bike for my wife last October. The first purchased 11 years ago was a small hub unit Urban Mover , the second with a Bosch mid motor about 5 years ago, and the third with a hub motor. Had I been willing to spend the extra 300 I would have purchased her a mid motor drive also. All three bikes are in working order, although the older urban mover could well use a battery replacement ..it being the earlier 200w motor, 28 volt pack.
The cycling experience is just much more natural with the mid motor. There are other obvious advantages which is that the motor is operating at maximum efficiency.
Now the so called problems... When and how often does a chain break?. I have been cycling on and off for 60 years and I don't recall that problem. Yes the chain has slipped off a cog ,and wrapped itself around the rear axle,.. bringing me to a rapid halt with a locked back wheel, and paradoxically chain slipping has been more of a problem with the first ebike, after 5 years. So that the argument that you can cycle along without a chain is correct..I have done so.
Of course all the power in a mid motor travels through the chain,and there might be a expectation that it will wear. However higher specific Ebike chains are available,and fitted to midrange bikes.
The wear on the wheel with a hub will be higher.. the spokes are shorter, hence less flexible, the starting torque higher ,and spoke loosening more of a problem. Again I had this problem and had to get the wheel rebuilt. This problem worse with smaller wheeled bikes.
The complaints in Germany are in the context of many millions of commuter machines in operation,.
Hub motors are a cheaper technology ,and these Continentals value efficiency over price.
What is being ignored in your answer is what happens in the case of an electric failure?. Battery etc . The frictional losses and magnetic reluctance losses,(except where there is an internal clutch), on a hub are much higher. My experiences with my Urban Mover was that riding it without power was like treacle. On the mid motor, there is no power loss.

Now the original question was reliability for commuting , and I would suggest there is very little in it.. although the Mid motor would win if steep hills are included.

 

[Woosh]

the frictional losses and magnetic reluctance losses,(except where there is an internal clutch), on a hub are much higher.

from this comment I can see you haven't ridden modern hub motor bikes (like my 16.5kg Faro which has an Aikema motor with 1:12 reduction) for many years!
The motors inside the hub motors are no less efficient than those powering the mid drives. The only difference is hub motors have the stator in the middle while some crank drives have their rotor in the middle, the latter configuration (with the copper wires farther from the middle) yields better heat dissipation.
The mechanical loss through the reduction gearbox is about same for both strategies. What may give the impression that crank drive is more battery efficient is the fact that statistically, most crank drive bikes have torque sensors and most hub drive bikes have cadence sensors. That's down to commerce. You have to pedal hard to ride fast or climb hills with a torque sensor to extract more power output from the motor while those with a cadence sensor don't have to.

 

[BazP]

What if its very cold, what if its raining or snowing or hailing and you dressed for a warm ride, or lightning is hitting the trees around you, what if its very muddy, what if you simply have no time for it?
Simply no need to if you have a cheaper, more reliable Hub drive bike!
Just use the PAS to get home and do the job when you have the time and interest!
It will usually happen far less often on a hub bike as well!
Just "funning" with you as I don't think you thought that quip fully through!
And I believe anyway, a mid motor rider is better off with a new chain, of the correct length, oiled up and properly packed somewhere on the bike, probably lighter than the tools and far quicker to fit.
And if a chain broke, you probably need a new one anyway, generally speaking.
In over 8 years of e-biking, I only once had a chain break after a small accident on a big rock up in the forest.....I removed the chain completely and simply got going by peddling to activate the PAS system, luckily one with no torque sensor of course, though possibly a tie wrap might help to simulate torque , though I have never even seen such a sensor! Guessing only!
My present bike has a strong guard, welded to the bottom of the frame, to make that area of the chain ring far less likely to hit anything....Something new to me personally.
regards and have a great day!
Andy

Isn’t riding a hub motor bike without the means to pedal assist illegal?

 

[John F]

from this comment I can see you haven't ridden modern hub motor bikes (like my 16.5kg Faro which has an Aikema motor with 1:12 reduction) for many years!
The motors inside the hub motors are no less efficient than those powering the mid drives. The only difference is hub motors have the stator in the middle while some crank drives have their rotor in the middle, the latter configuration (with the copper wires farther from the middle) yields better heat dissipation.
The mechanical loss through the reduction gearbox is about same for both strategies. What may give the impression that crank drive is more battery efficient is the fact that statistically, most crank drive bikes have torque sensors and most hub drive bikes have cadence sensors. That's down to commerce. You have to pedal hard to ride fast or climb hills with a torque sensor to extract more power output from the motor while those with a cadence sensor don't have to.

from this comment I can see you haven't ridden modern hub motor bikes (like my 16.5kg Faro which has an Aikema motor with 1:12 reduction) for many years!
The motors inside the hub motors are no less efficient than those powering the mid drives. The only difference is hub motors have the stator in the middle while some crank drives have their rotor in the middle, the latter configuration (with the copper wires farther from the middle) yields better heat dissipation.
The mechanical loss through the reduction gearbox is about same for both strategies. What may give the impression that crank drive is more battery efficient is the fact that statistically, most crank drive bikes have torque sensors and most hub drive bikes have cadence sensors. That's down to commerce. You have to pedal hard to ride fast or climb hills with a torque sensor to extract more power output from the motor while those with a cadence sensor don't have to.

Interesting tgread. I've had 2 Woosh bikes. The first was a crank drive which I had for 6 years and did 6000 miles. I bought it because I believed it would be better on hills (hardly a problem in York anyway) It was great but the thing that annoyed me most was having to be in the correct gear when applying power and certainly not change gear when under power otherwise I got some crunching noises which didn't sound good at all. I slowly came to recognize the shortcomings of putting that extra power through that that very narrow chain.
My rear hub bike doesn't suffer the above. Also, to my pleasant surprise, it goes up hills better than the crank drive, contrary to what many folk on this forum say. So what's that all about then? I'm firmly in the hub camp. I like the simpler construction, and now consider crank drives unnecessarily complex.
Interesting comment above on the vulnerabilty of the sensor. Are they easily damaged? Perhaps a home made cover superglued on might be an idea !.....

 

[Andy-Mat]

I'd say hub for commute. These motors are as near bullet proof as you'll get. Plus you don't have the motor dictating your cadence range. With a pas system, at the end of a long working day, you can ghost peddle home if you want.
I have 3 front hubs (none used for commutting 'cos I'm self employed) one with 7k miles plus on it. No issues, no broken spokes, no broken forks. That said if/when I convert again it will be a rear hub.

I also prefer hub, and both of mine have rear hub, which from a technical viewpoint I prefer, except if I get a rear puncture, though I can usually repair without removing the wheel....
Andy

 

[Andy-Mat]

Isn’t riding a hub motor bike without the means to pedal assist illegal?

As you actually have to pedal to get the PAS to operate, who is going to notice?
But if you wish to remain legal, you can walk if you wish, but I would be astounded if the police even said anything after seeing no chain!!!
Its the best reason to have hub over mid motor I find, plus of course the generally lower maintenance costs of course!
I have never had a bike with a torque sensor, does anyone here know if you can "fool" it with something like say a tie wrap, if the chain breaks?
Andy

 

[Woosh]

I have never had a bike with a torque sensor, does anyone here know if you can "fool" it with something like say a tie wrap, if the chain breaks?

no, that won't work. The torque sensor only operates when you have a cadence signal as well so that the controller knows that you are moving, not just resting your foot on the pedal at traffic lights.

The torque sensor has a special quality, it acts immediately like the throttle.

 

[Andy-Mat]

no, that won't work. The torque sensor only operates when you have a cadence signal as well so that the controller knows that you are moving, not just resting your foot on the pedal at traffic lights.

The torque sensor has a special quality, it acts immediately like the throttle.

Many thanks.
I am now very happy that I have never had one on a bike!
Regards
Andy

 

[BazP]

Many thanks.
I am now very happy that I have never had one on a bike!
Regards
Andy

Like Danidl above, I have never had a chain break in many years of analogue cycling and 5 years of electric cycling. I do carry spares for most contingencies including spare links and mech. hangers etc. but on the balance of probabilities I would expect to have more trouble with a complicated electrical motor, be it hub or crank, than a mechanical hardened steel chain.

 

[Danidl]

from this comment I can see you haven't ridden modern hub motor bikes (like my 16.5kg Faro which has an Aikema motor with 1:12 reduction) for many years!
The motors inside the hub motors are no less efficient than those powering the mid drives. The only difference is hub motors have the stator in the middle while some crank drives have their rotor in the middle, the latter configuration (with the copper wires farther from the middle) yields better heat dissipation.
The mechanical loss through the reduction gearbox is about same for both strategies. What may give the impression that crank drive is more battery efficient is the fact that statistically, most crank drive bikes have torque sensors and most hub drive bikes have cadence sensors. That's down to commerce. You have to pedal hard to ride fast or climb hills with a torque sensor to extract more power output from the motor while those with a cadence sensor don't have to.

Woosh, you are better than that. My arguement about efficiency is that motors have a natural speed range over which their efficiency is high and it drops off when rotating much slower or higher... with a mid drive that is possible. With hub drive it is not.
Secondly the other point is what happens when the cyclist is peddling faster than the motors speed. In a mid drive a very light clutch disengages the motor and gear assembly. Where is the clutch on on hub drive? .. even if present the planetary gears are rotating and this is pure drag. .. especially when there is no power assistance.

 

[flecc]

In a mid drive a very light clutch disengages the motor and gear assembly. Where is the clutch on on hub drive? .. even if present the planetary gears are rotating and this is pure drag. .. especially when there is no power assistance.

It's no different, the clutch on hub motors is between the motor and the planetary set. The latter set rotates with the wheel without any gear rotation so no drag.

In fact there have been mid drives with gears that had to be rotated by rider effort when pedalling without power, the original Panasonic mid drive unit for example. And on the small chainwheel Bosch motor all rider effort goes through a planetary gear set.
.