Hub or mid drive?

Joined
Jan 16, 2011
Messages
712
Location
Vilvoorde / Flanders / Belgium
Emiel, as assist 250W is enough.

The biggest motor I have around is a Revolt 160S 58KV. With Euan 400A controller. (Custom build)

Was ment to electrify an old Suzuki ER50, but that project went nowhere.

Other motor I have available is a SYM 125cc scooter motor with drivetrain (wrecked SYM GTS Evo scooter)
 
Joined
May 31, 2013
Messages
3,980
Location
South Benfleet, Essex, England, UK
I agree that the ridiculous 1000W and above motors are unnecessary.
Euro law is 250W and you are speed limited to 15MPH 25KPH. Anything greater than this then the trike/bike is only allowed "off-road" and any accident (your fault or not) makes YOU liable as you had no legal basis for being on a public road or path. People seem to forget their responsibilities and how the law views breaking the rules.
 
Joined
Sep 16, 2018
Messages
1,356
Location
Netherlands
I am looking ad a 350w motor for as I use a trailer. But probably better to stick with 250w for as I go over the border. In the Netherlands there are to many bikes, so you can do what you want.

I noticed the power of 250w and don't understand why you need a lot more. Maybe up to 500 in the mountains.
This time I go for a Bafang mid drive. More possibilities with settings and a bit more power for the trailer. But no torque sensor. That is the only thing that makes me doubt between the Tsdz2 and the Bafang.
 
Joined
Sep 16, 2018
Messages
1,356
Location
Netherlands
In short. Mid drive is giving the most power and gives you the longest range. On a normal bike, the position is also the best.
On a trike, a hub motor doesn't bring that advantage of position of the weight. You can compansate that with the battery.
A rear hub motor on a recumbent is a good option. I prefer mid, for how easy it is to mount and also makes it easy as you want yo put it on an other bike.

Pedalec is for me a big no.
Only allowed on the road and not on cycle lanes in the city out here. So noting better than a car, especially not in the rain. In the city, you won't be any faster than a city bike in the Netherlands. In most cases a city bike will even be faster.
Also a helmet is something that I will never wear. That's the biggest no for me and most Dutch people.
 
Joined
May 31, 2013
Messages
3,980
Location
South Benfleet, Essex, England, UK
I too think the Mid-drive is the best option, as it allows you to create a machine to your personal preferences.
If there is one drawback with Bafang it is the restrictions it places on Chainring choices. The best I have managed (with adaptations) is 2 rings 46 and 34, but the changer had to be mounted on an outrigger attached to the post on the bottom bracket. OTHER mid-drives that just act as a chain-chucker somewhere along the chain's length are available e.g. Cyclone.

What I have found to suit me is Bafang in conjunction with a Nuvinci N380. However, at the moment I am Bafang & Battery Pack rich as I am running my trikes without e-assist in order to redress muscle wastage.
The ability to swap out my front chainring(s) for a Bafang and e-assist my trike at any time is very appealing. I do not have to carry the weight of e-assist (motor + batteries) until I have to, but the trike's general characteristics will not change when I choose to do so. ;)
 
Joined
Sep 16, 2018
Messages
1,356
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Netherlands
For the tsdz2, they have adapters, so you can put a wider range of gears on it. But I only was thinking to put a slightly bigger one on. I don't need 2.

That you can swap it easily and fast is the nice thing of a mod motor.

That cyclone system looks like how I wanted to do it in the beginning. Wanted to build the motor behind the seat and turn it around. So a I could connect it to where you normally place the disk brake.
I still like that system. But a mid motor is easy to swap and has everything as a set.
 
Joined
Feb 20, 2013
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869
Location
Axedale, Victoria, Australia
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axerail.coffeecup.com
Bafang or not Bafang. That is the question.

The Bafang is, out of the box, a single chainring affair but there is a choice of chainrings available. Which one do you get? That is another question.

Try and work out which two chainrings of a "standard" chainring set you could do without. Lose the high and low and, you guessed it, you lose all your lowest range and your highest range of gears. Lose the middle and highest chainrings and you only have the lowest range of gears. Lose the lowest and middle chainring and you only have the highest range. Which matters most?

My first two-wheeler position, after all I would have assist, was to lose the low and middle chainrings and settled for a 46t instead of the original 48t high chainring. The biggest problem, assist off, was when starting off. Think about what it would be like with only the high chainring. Drop the size of it and you start to lose high speed. Chain angle on the lowest rear wheel gear was also severe. Not a problem with a tadpole due to the longer chain. I have also "fiddled" with a mid-drive but still found myself wanting a lower gear in some places where I ride.

I fixed the problem with a modification. I found a chainring set with a 5-spoke spider and removed the low chainring that I ended up adding to my Bafang with the addition of a steel disc, two kitchen cutting board spacers, 5 short 5mm bolts and longer 5mm fixing bolts to bolt the assembly to the motor. The additional low chainring sits on the inside of the large one. I don't have a derailleur on the assembly but since I manually put the chain on the lower chainring, I haven't moved it back. Due to Covid, I haven't used it much anyway.

In short, my view is that higher ranges are not the problem but there is with the loss of the lower gears. Try starting off on a steep slope with just a high chainring and you'll see what I mean. Come to think of it, I could probably do without the mid-drive now. I will have to look into it further.

You can find details in a posting of mine in a thread here somewhere. Just ask a question on my eLecTricks thread if you want.
 
Joined
Sep 16, 2018
Messages
1,356
Location
Netherlands
With me it was Bafang or Tsdz2.

Ad first I was afraid that I would miss the front 3 gears, but I don't live in the mountains, so a single is working good for me. But yes, that is something that can be a problem as you switch from hills to flat or the way around. But maintain bikes have solved that by putting an 11 or 12 gear in the back. I have 9s wide range and that works for me.
I wanted 2 gears on it, but I don't need it, but it is possible.
 
Joined
Sep 16, 2018
Messages
1,356
Location
Netherlands
I received my Bafang 350w 36v mid motor with 860c display.
I removed today the Tsdz2 from my trike and I am placing that one on my Gazelle. Than I have a great city e-bike.

I ordered with the bafang, a gear sensor. That turns off the motor by shifting. That lowers the wair on the chain and makes shifting go easier.
Going to build that motor on my trike in the coming days.
 
Joined
Jan 16, 2011
Messages
712
Location
Vilvoorde / Flanders / Belgium
I'm adapting my Bafang to work with a 46T and 40T. I don't dare to go lower, as the Alfine 11 I use is limited in torque. (and 40 is over the edge already, luckey I'm restricting the motor.)

But I already know, once funds are available, Rolhoff, here I come. And geared for low top speed with assist (25mph). It's plain nuts to go over 15mph in normal Belgian traffic, and even on dedicated bikepaths 25mph is "not conductive to good health".

I did look at the best combinations of IGH's, but with the knowledge 8 months ago, I didn't think about torque. The Envolio Cargo is rated for 100Nm. Shimano Nexus, don't even think about it. Shimano Alfine11, 130Nm. the Alfine 8 goes a bit over that. But the Rolhoff is the holy grail with 220Nm.

If low speed and torque is the thing, cassette is the way to go. Untill the chain snaps, you're good to go .
And trikes have the advantage here. Trikers just relax in their reclining chairs @ 0.5mph (if the gearing allows it)
 
Joined
Oct 19, 2012
Messages
2,384
Location
Wakefield, UK
I'm using an N330 Nuvinci hub with 750W or will be when it's finished. They're only rated at 350W but there's a chap here who runs 1300W through a N380. He uses a Bafang motor which hits peak torque immediately unlike the Tongsheng I'm using with it's torque sensor. I'm hoping that will allow me to get going steadily before giving it some beans. If the Nuvinci expires I expect I'll revert to a more standard rear end.
 
Joined
Sep 16, 2018
Messages
1,356
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They are getting cheaper by the day.
The torque sensor makes that you can easily change your speed. It rides more like a normal bike and it reacts to your input. Not like the other sensor that reacts on movement and Kers hoping, as long as you pedal.

As I get a hub motor, I will also use a torque sensor on it.

They have other firmware for the Tsdz2 that brings more torque. I keep it stock, because I don't need it. It is strong enough and I like how it rides now. It is smooth.
The bafang rides different and I tried it on soneone else his trike. The bafang had more torque and because I want to ride with a trailer, I went for the Bafang.
 
Joined
May 28, 2013
Messages
120
Location
Ottawa
So, while the welder is still gathering dust, and I start to have free time again I'm looking to modify my commercial TerraTrike GranTourismo. They used to have a Falco based hub motor conversion kit, but issued a recall, and have now gone over to the Bosch mid-drive on a replaceable boom. Price point is oof!

In my case, before I'd pay shipping and custom's fees I'm buying the GT all over again. So, I've started researching, factoring in my mass, the trike's mass, the gear I anticipate carrying, and thanks to the folks over at Grin Technologies (not advocating or shilling for them - I'm just really impressed with the info they make available - including a very good pro's and con's discussion on mid vs hub drive bikes) I'm seriously considering the GMAC direct drive or something similar - the Grin Technologies Cycle Analyst V3 seems to have a way to program in a virtual freewheel effect so that you don't fight the resistance of the magnets - they draw just enough power to overcome it. I may still skip that, and go for a freewheeling hub motor - that way I won't fear a motor or electronics fault keeping me from getting home, or at least to a vehicle accessible pickup point. There are enough places on the routes I plan to ride/commute that calling for a pickup means a very long uncomfortable walk pushing the trike. (Cycling shoes just don't have the best flex for walking y'know? :))

On the flipside, she-who-must-be-obeyed, discovered riding an upright is no longer for her various joints, and we lucked into an ad for someone selling off one of the Chinese made Zmerk suspension trikes with e-assist already built in - she's now fairly sold on recumbent trikes. It's a hub motor system - so far, no service required other than shortening the boom to allow it to fit her, and a T-cycle cockpit mount to put the controller in a better spot. It's quite quiet, and I have to work to keep up with her when her knees give up and she engages the assist. She has now developed bad habit of wanting to talk to me at the top of a hill where we usually have to wait for the lights to change, and well, I resemble a very tired horse with the huffing and puffing I do.

I'm hoping to use this conversion experience to help me work out some kinks for a possible build - y'know, knowledge in the tool chest as it were!
 

Ian

Joined
Nov 7, 2021
Messages
13
Ignorance is bliss. I am planning a Warrior with e-assist later on. Above 250w pedelec is illegal here. I was wondering if a Sturmey Archer 3 speed hub gear would take the extra torque or disintegrate under the load. This would allow me to fit a 20 inch rear wheel. A derailleur will hang very low an so require a larger wheel. This will resolve what hub to use and the size of the rear wheel to build. I like the idea of less maintenance of hub gears. Any thoughts would be appreciated. Have a Merry Christmas.
 
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