Rear hub vs mid drive

John Thompson

Active Member
I'm interested in a cross country/packed gravel fire roads bike that will involve some pretty good hilly climbs, for somewhere around $2000. How big a difference are entry level mid drives vs good rear hub drives at this price point, in terms of power for these types of climbs? Comparing something like the Voltbike Enduro vs a hardtail like the Magnum Mi6?
 
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this article is a bit old. mid drives also have torque sensing and can have shift detection. plus they are more efficient don't need as large of a battery and they let you have a decent cadence.
 
This is a good and common question that has been hashed over so many times here. The search function works well so rather than asking folks to retype thoughts already shared, I suggest do some searching.

That said, the general (but not universal) consensus has been that for "cross country/packed gravel fire roads bike that will involve some pretty good hilly climbs" a good mid drive bike with a torque sensor will get you up hills better than all but the very best, power guzzling hub motor, with less battery power used.
 
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OP, spend some time using the ebikes.ca motor simulator. There are some very capable hub drives. You can actually simulate the power used and plug in the road grades.
 
You can find high quality mid drives for that price point on sale. If you can go up to 3K there are some very nice full suspension mid drives around which is perfect for country roads / light trails. I wouldn't go hub motor in your case.
 
You can find high quality mid drives for that price point on sale. If you can go up to 3K there are some very nice full suspension mid drives around which is perfect for country roads / light trails. I wouldn't go hub motor in your case.
How can we negate hub drives without knowing the grades being ridden up? BTW I do tech support for mid drive system. I also ride or have built MAC and eZee geared hubs.
 
How can we negate hub drives without knowing the grades being ridden up? BTW I do tech support for mid drive system. I also ride or have built MAC and eZee geared hubs.
Of course we can not completely negate them. I am sure a beefy hub will deal with most hills easily and they have many advantages.

But when you ride exclusively on fire roads, light trails etc. usually you come across one of those extremely steep sections which slows you down to a crawl, may have to deal with rocky terrain etc. and your speed is usually low, IMO a full suspension mid drive is the safest bet under those riding conditions. Being able to fix flats easier than hub motors is another plus.
 
That said, the general (but not universal) consensus has been that for "cross country/packed gravel fire roads bike that will involve some pretty good hilly climbs" a good mid drive bike with a torque sensor will get you up hills better than all but the very best, power guzzling hub motor, with less battery power used.
Several of the opinions here mix up Direct hub drives with geared hub drives. Statements about hub drives that mix the two types are generally glosses. Direct drive hub drives are inefficient at low speed especially on hills. Geared hubs are much more efficient than direct, but can't sustain full power runs uphill of more than 15 minutes, or they overheat. Full power on my hub is 15% grade at 310 lb gross load and can adjust from 0 to 6 mph on that grade from a dead stop. 350 W geared hubs that are state law compliant may be much less capable.
I agree with the opinion, PAS is ****. Much too fast with too much acceleration for roads outside very rich cities that fill potholes in hours. there is one hub drive bike now with torque sensor xstream catalina, and mine may follow the leader. Until then I use throttle only.
One trades off having to unsecure wires & torque arm when changing tire on hub drive, with not having to change chains for thousands of miles. 5000 in my case, 2 1/2 years. I get 2000 miles per knobby kenda tire, usually without flats. Mid drive chain life has been reported as low as 500 miles in one case with 11 speed sprocket. BTW changing tube on the hub motor end with torque arm is quicker than than changing the derailleur end, since I usually have to wind up the chain take up with chanllocks and adjust it a couple of times putting back on.
 
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OP, spend some time using the ebikes.ca motor simulator. There are some very capable hub drives. You can actually simulate the power used and plug in the road grades.

But one can only stimulate the motors sold by Grin. We outsiders with the cardboard belts won't know whether our cheap motors will burn until we smell smoke.

If budget doesn't matter though, get the mid drive and learn how to use the gears. Now you're prepared for any hill.
 
But one can only stimulate the motors sold by Grin.
Not true. The list is expanded considerably MXUS, nine continent, Bafang mids and hubs, customizable inputs, and more. I just saw Q100 has been added. No Bosch, Shimano, or top tier mids unfortunately.
 
If your trip is going to be long and far from any big cities then consideration must be given to reliability. A non geared hub drive has one moving part, no gears or belts. That simplicity makes it more reliable. It may not be ideal for steep hills but it will help you. On flatter terrain the direct drive hubs are speed demons.
If you have a van following you for support go mid drive. If your alone direct drive hub.
 
If your trip is going to be long and far from any big cities then consideration must be given to reliability. A non geared hub drive has one moving part, no gears or belts. That simplicity makes it more reliable. It may not be ideal for steep hills but it will help you. On flatter terrain the direct drive hubs are speed demons.
If you have a van following you for support go mid drive. If your alone direct drive hub.
That’s a bit overstated. A well maintained mid drive can be very reliable. A clone hub drive can be very unreliable and easily overheated. Stator Aid injected into a direct drive hub can cool things down considerably. IME there’s really no one size fits all. The devil is in the details. I’m speaking from experience and currently running with mids, DD, and GHD. Each has its place.


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airflow.



The idea behind Statorade is brilliant and simple. A direct drive hub motor generates heat internally at the stator, but this heat has no easy path to escape since it is surrounded by trapped air. It is possible to cool the motor with vent holes and active airflow from outside, but this exposes the motor to the elements. Alternately, filling the motor with oil will cool the stator windings quite well, but with significant increase in motor resistance from fluid drag and an enormous sealing challenge to keep the oil from leaking

With Statorade, only a tiny amount of fluid is needed to achieve the same effect. Nanomagnetic particles suspended in a low-viscosity oil concentrate this liquid in the magnetic air gap of the motor. That is exactly where it needs to be to transfer heat through fluid convection between the motor stator to the motor shell, where the heat can then be easily shed to the environment via passing airflow.

Statorade Ferrofluid Heat Flow Diagram


The magnets on the rotor trap the fluid in the gap so that it can’t splash around and leak out through the ball bearings or cable wiring as happens with normal attempts at oil cooling. And it turns out that only a tiny amount of Statorade fluid is needed to achieve heat transfer, resulting in negligible effect on the rolling drag of the motor.
 
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