Quiet motor advice for low top speed but high torque

I'm trying to ascertain what is the quietest motor, whether hub or mid drive. I am not looking for top speed as this may go in a faired recumbent, so it is for help climbing hills. On the flat I do not need assistance. I would like it to be legal, which is 250W continuous where I am based in the UK.
I am currently using a TSDZ2 but would like something quieter and with no cogging or resistance as most of the time I will not need assistance. I notice that despite there being a freewheel in the TSDZ2, there is resistance.
As the bike is enclosed, sound amplifies so the quieter the better.
I do like the torque sensor in my current setup, and am apprehensive of the Bafang BBS in that regard.
From reading various forums the BBS01 or 02, or a MAC hub drive seem to be what a fair amount of people seem to be using. I haven't tried either; are they silent or indeed is there a quieter motor out there that would suit my needs?
Appreciate your advice or thoughts on the aforementioned.

Quieter is a DD hub motor, but it won't produce a lot of torque at 250w. A small wheel and a slow winding would help, but 250w is still 250w, and gear reduction is the only way to multiply the torque of a motor.

You could build a mid drive using a small DD hub. You could mod your actual system to make it more quiet, using a sine wave sensored controller, and improving your drive train to reduce noise. You could use a geared hub...

The best solution is higher power and a DD hub motor wheel. This would make it illegal, but a hub is not obvious on a faired recumbent, and you are not riding fast anyway. No motor is as silent as a brushless DD hub, and none has a comparable reliability, life expectation, and simplicity.

The 48v 201 rpm Q128 with a KT sine wave controller will give you exactly what you want. If you have casette (free-hub) gears, get the Q128C otherwise the Q128H. These motors give torque in spades and with those controllers are as good as silent. They're nominally 500w and 800w, but the label easily peals off, then it looks the same as any typical 250w motor. Nobody would question it.

If your sure about wanting low speed, the absolute maximum of the 48v 201 rpm versions on the road is 19 mph. The 201 rpm 36v versions run at 48v will go to the mid 20s mph. Whichever version you have, you can limit the max speed in the LCD settings to make it legal.

Sine wave will run quieter. If the gears are noisy, re do the lube as often as needed.

It would be fitted to a chainring on the left crank side (so not an in-wheel unit) and the motor would be mounted in front, on the boom ahead of the BB (not sure how yet, some mount would have to be fabricated).
The wheel it would be powering would be 20 inches but it may be used to pull a trailer as well so the weight of the bike could be fairly heavy, circa 100kg system weight (me and bike) without trailer.
I would like it to assist at higher cadences, between 70-110 as one spins at a higher rate with recumbents and with shorter cranks.

I have a 36V battery with my current setup so could use that, but will it be able to support the higher cadence that I desire or would I need a 48V battery?
With the Q unit can one decouple the motor when one pedals beyond a certain speed, say 15mph, so there is no resistance? Just found this from you on pedelecs, 'It also has the advantage that it's between the gears and the hub, so the hub becomes completely free when free-wheeling' so that's a yes then.
Will a Thun sensor be required, as I like the torque sensor in the TSDZ2, or is this torque simulation on the controller sufficient?
Do these hub motors run hot, as it would be placed in an enclosed vehicle?
It may have an IGH as well as a cassette but most of the time the hub gears would be used so I guess the H? The IGH would not be mounted in the wheel, it would be a mid-drive.
Any difference in running the 48V 201 RPM unit compared with the 36V 201RPM unit aside from the ability to achieve higher speeds? In terms of noise or weight/size?

Where does one find the controller and where is the best place place to purchase these hub motors (BMSbattery.com or elsewhere) and does one need to pair it with a CA or is a KT-LCD3 the right one to get? I just found your comments on the pedelecs forum; is this the KT sine wave controller https://bmsbattery.com/controller/698-sine-wave-controller-for-09-case-controller.html?
Is it the front or rear hub version of the Q128H that I need?
How do I attach a cog or sprocket to the hub? Are there bolt fixing holes on the hub itself? Can't find images online but there must be some somewhere.

Will also search for forum topics on this motor.

This motor/controller combination is really quiet; this is more of what I am looking for in term of lack of noise; he doesn't mention the parts aside from the controller though: https://www.youtube.com/watch?v=500NOesKoBQ
Noise in a hill test scenario would be good; if you know of a video that illustrates that, that would be helpful.

So if I go with the above, shopping list would be: Q128 with sine wave controller kit and anything else (if I use my existing 36V battery)?

I believe the Q128H is a screw-on Freewheel, where the Q100 CST has a splined Freehub which is cassette ready.

It may be a bit stressed in your application. These are lightweight units designed for typical loads of up to 250 lbs max. Clutches and gear life are reduced with higher loads.

If this is a daily commuter miles pile up quickly, and tend to put a bit more emphasis on reliability. It would be prudent to "overspec" a geared hub when its used for commuting. I would be looking at the MAC Upgrade Cassette or Bafang 500W Cassette geared hubmotors. Typically about 3000-5000 miles of power-on gear/clutch life. Less for the Q128H.

As for controllers the Grin Tech "Grinfineon" Sine Wave controllers are pretty robust and quiet.

For me, the service life on geared motors would make me consider a Direct Drive. Sure you get the cogging and other drawbacks but it is the most reliable booster rocket.

We're considering running a test on a Golden Motors Magic Pie Edge. This will go on the trike to replace the currently equipped with a TSDZ2. I've been developing a new under Boom mounted battery tray for Shark/Bottle battery packs as we prep it for a new hubmotor.

Here's a little rag on the MAC Motor:
http://www.triketech.com/Drivetrain/PowerAssist/HPV-MAC-V2.html

Thanks Triketech.
No, it's not a daily commuter so don't intend to do high mileage on a day to day basis although it may be used for long trips where the mileage would rack up, it would be used for the hills and a few traffic light starts. Trailer will unlikely be used much with this bike so the weight the motor will generally assist would be 100-130kg.
Can one decouple the DD motors? When one is pedalling without assist for the majority of the time one wants the least resistance as possible.
The Q128H is rated at 800W.
The TSDZ2 motor that I currently use doesn't peak at that wattage and has pulled a system weight of 180kg. Why would this geared hub motor be less reliable and more stressed?
I do know someone who is riding a similar bike, with Golden Pie motor installed; they moved from a 250/350W Crystalyte hub motor which wasn't quite powerful enough for their needs.

One can eliminate the cogging resistance of a DD motor by feeding it a very very low wattage. 25w or so will do er, the problem usually is having an assist level so low you get no more than 25-50w. This is solved by the more modern controller and display, that has 5 levels of assist, vs just one, or just three. Level one will do er.

At 25w,, 100 watt hours of battery takes you for 4 hours of pedaling without DD cogging. That's about 36v 3 ah. Not much to carry, to eliminate the need for a freewheel. And, you wont hear any internal gears.

Dogman - Interesting suggestion...what would the resistance in wattage be if the motor was switched off? On the other hand, can the motor be decoupled from the transmission altogether, given that the motor would be connected to the left crank/chainring via a chain and the right crank/chainring leading to the rear cassette or IGH?

So three options thus far:
Q128H - Light but possibly not reliable enough?
MAC - Heavier than Q but slightly more reliable?
DD, e.g. Golden Motors - Heavier again but the most reliable and quietest in this context?

I have also spoken to Lightning Rods, and he's thinking of making a lighter weight mid drive, slightly lower power than he normally builds, that's also quite quiet.

Triketech - Look forward to hearing about how the Golden Motor setup works on your trike.

aja said:

Dogman - Interesting suggestion...what would the resistance in wattage be if the motor was switched off? On the other hand, can the motor be decoupled from the transmission altogether, given that the motor would be connected to the left crank/chainring via a chain and the right crank/chainring leading to the rear cassette or IGH?

So three options thus far:
Q128H - Light but possibly not reliable enough?
MAC - Heavier than Q but slightly more reliable?
DD, e.g. Golden Motors - Heavier again but the most reliable and quietest in this context.

I have also spoken to Lightning Rods, and he's thinking of making a lighter weight mid drive, slightly lower power than he normally builds, that's also quite quiet.

Triketech - Look forward to hearing about how the Golden Motor setup works on your trike.

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I don't get where you got that info from. Can you show me any Q128 that ever failed?
Golden motors re not quieter than a Q128 with a sine-wave controller.
What makes you think that Golden Motors are more reliable than the other two?

d8veh said:

aja said:

Dogman - Interesting suggestion...what would the resistance in wattage be if the motor was switched off? On the other hand, can the motor be decoupled from the transmission altogether, given that the motor would be connected to the left crank/chainring via a chain and the right crank/chainring leading to the rear cassette or IGH?

So three options thus far:
Q128H - Light but possibly not reliable enough?
MAC - Heavier than Q but slightly more reliable?
DD, e.g. Golden Motors - Heavier again but the most reliable and quietest in this context.

I have also spoken to Lightning Rods, and he's thinking of making a lighter weight mid drive, slightly lower power than he normally builds, that's also quite quiet.

Triketech - Look forward to hearing about how the Golden Motor setup works on your trike.

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I don't get where you got that info from. Can you show me any Q128 that ever failed?
Golden motors re not quieter than a Q128 with a sine-wave controller.
What makes you think that Golden Motors are more reliable than the other two?

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I have no personal experience of the above motors and have no access to these setups locally, which is why I am asking other people on forums and elsewhere. My views simply express the views expressed on this thread and on general comparisons between geared and non-geared. I have been informed that a DD vs a geared hub is quieter and potentially more reliable due to its construction, if one uses the same controller.

aja said:

d8veh said:

aja said:

My views simply express the views expressed on this thread and on general comparisons between geared and non-geared. I have been informed that a DD vs a geared hub is quieter and potentially more reliable due to its construction, if one uses the same controller.

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Most of those people have never even seen a Q128 nor used a KT sine wave controller.

I can remember when the 4 cylinder Honda motorbikes came out in the late '60s. People used to say the same thing: "Too many moving parts, can't be as reliable as a Triumph of a Harley D." Later on, they had to change their argument to: "They don't have character, like a Harley does." By that, they meant that they weren't noisy, didn't vibrate and bits didn't fall off.

d8veh said:

aja said:

d8veh said:

aja said:

My views simply express the views expressed on this thread and on general comparisons between geared and non-geared. I have been informed that a DD vs a geared hub is quieter and potentially more reliable due to its construction, if one uses the same controller.

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Most of those people have never even seen a Q128 nor used a KT sine wave controller.

I can remember when the 4 cylinder Honda motorbikes came out in the late '60s. People used to say the same thing: "Too many moving parts, can't be as reliable as a Triumph of a Harley D." Later on, they had to change their argument to: "They don't have character, like a Harley does." By that, they meant that they weren't noisy, didn't vibrate and bits didn't fall off.

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Would be really useful to be able to try one out. Do you know anyone who has the Q128 KT controller setup in the Hertfordshire or South East Area? Perhaps I should enquire on the pedelecs forum.

https://www.youtube.com/results?search_query=q128h+motor

Yup today I ran outta juice half way home, its hovering at 30V cutoff is at 28V so I gotta baby it, just a little throttle, just a hair.... then the KT display cruise function kicks in at 25W or 50W and I can pedal home. Its odd because when on my first run after the inspection of the pack, I got 55 to 65km on 30Ah going 30-35kph. Today I got 25km on 24Ah and I left my 6Ah at home. But I should keep that 6Ah in the pannier bag for times like that.

As for quiet motor = Direct Drive
Get a motor with a low turn count = high speed
A three or four turn count motor.
then lace the direct drive motor into a 16" motorcycle rim which equates to 20-21" bicycle rim. This gets you huge torque then you would get in a 26" in bicycle rim. This also allows for excellent cooling of the motor because you arent pumping the same amps through smaller wire/longer wire = higher resistance = high turn count motor. A low turn count motor = larger wire/shorter wire = lower resistance = push more amps through the windings.

For a low or high turn count of the same motor, the torque is the same, its the wheel diameter that changes that aspect. There still is that Myth out there which should be smashed.

I just bought a Xongda XD 2 speed geared hub motor. I still haven't built up my wheel but research tells me buckets of torque and a top speed of about 30kph. I bought it directly from the manufacturer, motor, controller, brake levers, display, throttle, torque sensor, hi/low/auto switch, spokes & shipping was $250USD. Bonnie answered all my questions and was great to deal with.

BCBeaver said:

I just bought a Xongda XD 2 speed geared hub motor. I still haven't built up my wheel but research tells me buckets of torque and a top speed of about 30kph. I bought it directly from the manufacturer, motor, controller, brake levers, display, throttle, torque sensor, hi/low/auto switch, spokes & shipping was $250USD. Bonnie answered all my questions and was great to deal with.

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They're also very helpful after you bought your stuff, which is unusual for Chinese sellers.

Personally, I found the Q128 motor to be pretty lame at 48V with a regular non-sinewave controller. Is there a big difference between the normal Q128 vs the Q128C or Q128H versions?
With the "normal" non-C non-H version, the Cute 100 was way better, and smaller. What am I missing?

chvidgov.bc.ca said:

Personally, I found the Q128 motor to be pretty lame at 48V with a regular non-sinewave controller. Is there a big difference between the normal Q128 vs the Q128C or Q128H versions?
With the "normal" non-C non-H version, the Cute 100 was way better, and smaller. What am I missing?

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I had the original 36v Q128. It was gutless, so I soon took it off and changed it to a BPM.

I then got a 48v Q128H, which was chalk and cheese compared with that Q128. It gave plenty of torque at 20 amps. I now have the 36v Q128C at 48v but only 14 amps. It gives more torque than that original Q128 that was at 22 amps. The Q128C feels completely alive, but that Q128 felt dead, even though it was being fed 150w more.

I can only guess that the Q128 had bad magnets or something like that. I can't say whether the latest ones are the same. I know MXUS made two versions of the same motor with different wire and magnets: One for the Chinese market and one for export.

Not sure I understand your question, from many posts back. But yeah, if a motor is connected to the crank of the bike, you can decouple it with a freewheeling chain ring. This is part of any good mid drive setup, bafang, shimano, bosch, whatever, either built into the system, or added to the crank itself.

Stokemonkey, at least originally, did not have this, so when you gave the motor some juice, your pedals would start to turn.

Always, internal planetary gear motors make some noise. So again a DD motor is the quietest. But what I have no idea of is how quiet you are insisting it be. Every geared motor I ever rode was pretty quiet when riding at low power, and low speed. Its when hauling ass that they whine.

dogman dan said:

Not sure I understand your question, from many posts back. But yeah, if a motor is connected to the crank of the bike, you can decouple it with a freewheeling chain ring. This is part of any good mid drive setup, bafang, shimano, bosch, whatever, either built into the system, or added to the crank itself.

Stokemonkey, at least originally, did not have this, so when you gave the motor some juice, your pedals would start to turn.

Always, internal planetary gear motors make some noise. So again a DD motor is the quietest. But what I have no idea of is how quiet you are insisting it be. Every geared motor I ever rode was pretty quiet when riding at low power, and low speed. Its when hauling ass that they whine.

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I can't give a specific DB rating as haven't measured mine and need to wait till I get my next velomobile till I install e-assist on that (TSDZ2 is currently fitted to my open recumbent trike. With a trike you have the motor in front of you so you hear it more than an upright bike. In a velomobile, you have the same situation but without wind noise and in an enclosed shell so more amplification. A belt drive for the rear gears and a belt drive for the motor or a quiet Hub motor connected via belt to the left crank ring would bring the noise level down. Belt for the rear is tricky for two reasons - on a recumbent you adjust for leg length via the boom which then of course alters the amount of chain you need; you can either have a rear derailleur or tensioner to take up that slack for small leg length differences or remove some of the chain. Not possible with a belt drive running from the boom to the rear axle. My aim isn't for high speed, but for good assist at low/medium speeds (sub 20mph), up gradients in particular.
How do you set up a freewheeling chain ring with a hub motor? What did Stoke Monkey do and what do they do now and how did they implement it (or any other companies/individuals that have done the same thing)?
Is this the kind of thing that you mean? https://www.youtube.com/watch?v=Q6pYanJqqf0

I installed Xiongda 2 speed on my son's trike. This hub is freewheeling and is relatively quiet. Most likely one of the best low power kits out there. Check this thread: https://endless-sphere.com/forums/viewtopic.php?f=3&t=58490&hilit=xongda
Forget about Lightning Rods it's all BS.

Ecyclist said:

...one of the best low power kits out there. Check this thread: https://endless-sphere.com/forums/viewtopic.php?f=3&t=58490&hilit=xongda

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Well, it is a long thread to read, but if you do...
You will notice that many have had problems with it, and lots of them are using another motor today. For this, I would not call it ‘one of the best’.

I understand that you are happy with it and didn’t have any problems, but reliability is the average of all the experiences. There are many, very reliable kits that would deserve better to be called one of the best.

Actually I had a problem with mine. I had to replace a sun gear. Only because of very good customer service from Xiongda I still recommend it.
If you are looking for product with no problems you better forget about buying a kit to convert a bike. They all come from Chine and all Chinese products will have something to take care of.
It is a Chinese rule ah.....roulette.

Have you found Rassy's trikes. Lots of good info on using direct drive hub as "midrive"