Xiongda YTW-06 mini hub motor

neptronix said:
I've really been thinking about building up a 700c wheel bike with one of these for months. This motor looks like just the ticket. 3lbs is freaking sweet.

Also it looks like this motor only takes a single speed freewheel from here.. is that true?

neptronix, I'd be very interested in seeing what you build with this motor.

So I special-ordered this motor with a 120mm width axle since I'm using it in a single-speed. But the motor comes stock for 135mm dropouts and uses a 6 to 7-speed freewheel—no cassette version as of right now. I think a few people have managed to squeeze in 8 speeds with less space between the cogs.
 
zro-1 said:
That video looks accurate to what I've been seeing as well. Thank you for sharing that JohanK! What's interesting, and I think JohanK was getting at this also, is that this motor feels much less stiff when you're rolling the bike around than when you just spin it freely by hand. For example when I felt how little it spun, I was worried it would have a lot of drag, but even just walking the bike I really didn't notice any more heft to it than when I had the Q100 on the same bike. And that Q100 definitely spun more freely than this motor does right now.

One thing I'll still point out is that supposedly this stiff clutch gets better as it wears in. FarthingPenny had DMed me and mentioned that he was talking to Bonnie from Xionda and it sounds like this motor uses a needle-bearing clutch that is situated on a hardened part of the axle. I'm not planning on opening my motor unless I have trouble with it (sorry) so I can't say with any certainty how this motor is built, but it has to be some compact multi-stage gearing to get 17.5:1 in this tiny shell.

I'll have my throttle and wiring bits on Thursday, so I should be able to get this bike on the road hopefully by Friday, but if not then certainly over the weekend. I'll take some video of the motor in different scenarios for you guys to check out.
The noise is not loud during operation, only the noise is a little louder and a bit annoying idling, but it may also be because the wheel and the rims are made of carbon and therefore more clairaudience. I think the engine should always be run with a minimum of electricity. Without electricity you can already feel the freewheeling resistance and a little more noise.
 
zro-1 said:
neptronix, I'd be very interested in seeing what you build with this motor.

So I special-ordered this motor with a 120mm width axle since I'm using it in a single-speed. But the motor comes stock for 135mm dropouts and uses a 6 to 7-speed freewheel—no cassette version as of right now. I think a few people have managed to squeeze in 8 speeds with less space between the cogs.

Oh, i see. Sorry for not doing my research. I didn't know xiongda does special orders like that.

I think your ultra light weight bike is already more exciting than anything i could come up with. I was just gonna throw one of these on my wife's 30lb chromoly 700c Trek and call it a day. Looking forward to seeing how your build pans out. :D
 
Initial motor impression, copied from my build thread:

Good bits first:

The motor performs really nicely! The motor's power and top speed at 48V is exactly what I wanted. It pulls enough that I don't have to work very hard up the hills, though I do have to work (which is what I wanted—assist, not pedal-less climbing). The top speed is good. I don't have a speedo, so I can't tell you exactly how fast, but Strava reports my top speed at 28.2 mph. I'm positive the bike can go a bit faster, but the twitchy steering had me a little nervous so I was taking it easy. At top speed I was still able to contribute pedal input without just ghost pedaling, which was one of my biggest complaints with the fast Q100.

The bad bits:

There's only two, the motor is noisy—even with the FOC Phaserunner. I don't even want to imagine what this thing sounds like with a square-wave controller. My BBSHD is the quietest, and on the Phaserunner I would say that the Q100 was only slightly louder. The YTW-06 is definitely a bit louder than both. It's not dramatically louder in terms of decibels, but the tone of the sound is more like an electric motor sound rather than the deeper hum of the Q100. My other dislike is the clutch; it's noisy too. I didn't feel any drag when coasting with no throttle or pedaling, but I could hear the clutch. It is just about drowned out by my loud White Ind. freewheel, but if I'm pedaling with no motor, it almost sounds like my brakes are rubbing or something (they're not, I checked twice).

I have read that both of these things get better as the motor breaks in and things seat with each other better. I will be sure to update either here or in the motor thread if and when that happens.

First impression conclusion:

With only the one 2-mile test ride, I can't make any proclamations about the motor yet. The weather this week is going to be awesome here in Atlanta, so I'm going to be getting 50-60 miles on it at least. So I will post again next week with my real ride impressions of the motor.

My first impression is that the smaller size and lighter weight make this a very nice mini hub motor. It is definitely without a doubt worth the $75 + shipping. If you're already running a Q100, I'm not yet certain it's worth swapping out just for the size weight differences. if you don't yet own a Q100 or the one you have has died, this motor should be at the top of your list when looking for a replacement/alternative. The motor seems to pull just about as hard as the high-speed Q100 did—which is pretty crazy for such a little motor. I think I can tweak settings in the Phaserunner to get this running even better. I was a bit conservative on my initial settings, and I didn't go near any of the advanced settings other than adjusting the throttle input levels.

This initial test was done with a 480W power limit from the Phaserunner, so with my 48V nominal pack, this motor would only see about 10A. It felt really good for just 10A and I can't wait to see how it is when I bump that to 12 or 15 Amps.
 
Kinda sad to hear that it's on the loud side with a FOC controller. I'm sure that the higher pitch is more audible, due to the high rpm and how the human ear works.
I expect other dual reduction motors to have the same effect.

If anyone can get a video of the noise, that'd be really helpful.
 
I've still not actually bought anything for my upcoming first build, and this motor really catches my eye. I have a few questions that I hope someone here can answer:

1. How much is shipping? Is it any better than BMSBattery?
2. What is the max voltage of the controller they send with it by default? Could it handle 13, 14s?
3. How does the torque compare to a Q100? I know this one has 40 Nm, but I can't seem to find the value for a 201 RPM Q100C.

Thanks.
 
The controller is available in 24/36/48V. You pick what voltage when you place your order.

Shipping is the same as BMSBattery, about $60 to Atlanta, GA USA.

The torque you get from either the Q100 or the YTW-06 will depend on a bunch of things, but most specifically, the amount of amps you put into the motor. The gearing would have an effect as well, but motor torque is really about how many amps the motor can take without melting or stripping gears. I'd assume that the 40Nm of torque Xiongda quotes is based on the power output of their controllers. They state that the motor is 300W max so that would be only 6.25A at 48V or 12.5A at 24V which I doubt very much they actually set the controllers at but I'd assume that 40Nm would be when the motor is getting 12.5A.

I'm currently running the motor at 48V, 10A and it's barely getting warm. I'm confident I can run this thing at 48V 12.5A (600W) and still be well within the safety zone for this motor. Even at 10A it's pulling almost as hard as the 328rpm Q100 at 18-20A by my seat-of-the-pants feeling. I think at 12.5-15A this motor will actually pull harder than the Q100. I don't know how it would compare to a 201rpm Q100 at the same power levels.

I would say that if the sound doesn't improve as the motor wears in, then if you don't mind a higher-pitched slightly louder motor noise, then get this. If you want similar performance/size and don't mind a little more weight, but don't want to hear the motor as much, get a Q100.

EDIT: also, this motor can only use a freewheel. So if you need a motor with a cassette, then the Q100c is your motor.
 
Here is the power graph, just for reference.

The maximum efficiency point is 333W on 36 volts / 11.1A on this ~230rpm wound motor pictured. I believe that this motor may handle 350-400 watts continuously on 36 volts. 48 volts might put you in 450-500 watt continuous territory in a 26 inch wheel or smaller.
These are just some conservative estimates based on the data sheet.

Keep an eye on those motor temps at 600w. It might be hard to find out where the stator heat is. Measure the temp on both sides of the case and the axle as well. As with most geared motors, if it feels hot on the outside, it's scorching on the inside because the thermal path from the stator to the case on these motors tends to be extremely poor.
 

Attachments

  • YTW-06 power.pdf
    100.7 KB · Views: 292
neptronix said:
The maximum efficiency point is 333W on 36 volts / 11.1A on this ~230rpm wound motor pictured. I believe that this motor may handle 350-400 watts continuously on 36 volts. 48 volts might put you in 450-500 watt continuous territory in a 26 inch wheel or smaller.
These are just some conservative estimates based on the data sheet.

Keep an eye on those motor temps at 600w. It might be hard to find out where the stator heat is. Measure the temp on both sides of the case and the axle as well. As with most geared motors, if it feels hot on the outside, it's scorching on the inside because the thermal path from the stator to the case on these motors tends to be extremely poor.

That's good info. I'm new to these small hub motors, so I'm not familiar with all of their traits and what to watch for. I should note that while I'm running this motor at 480W max right now (in a 700c wheel), I almost never use full power except for three steep, but relatively short hills. All the other times I'm either using 70% throttle or just 30% throttle. In fact, so far I'd say I'm using 30% throttle about 75-80% of the time I'm using any power, and that's only for about 70% of my total commute. The other 30% of the commute I don't use the motor at all.

When feeling the motor I'd been touching the center of the shell, the inside of the spoke flanges, and the side cover on the brake side. I hadn't thought of checking the axle itself, but that makes great sense. I'll try feeling the axle tomorrow after my commute to see how the temps are right by the cable exit.

Since I'm only using full power for short spurts followed by long periods of very low power or no power at all, I think I'd probably be able to run on 600W, but that may not hold true for everyone. If this motor follows many hub motors, it can probably run reliably on double the rated power, so for most people, this may be a 500W max motor. I'll of course post here if I do anything that cooks this motor.

Also, as far as the noise goes, it seems to be getting better to my ears—I don't think its because I'm getting used to it. I do think the motor has gotten a little quieter, but I only have about 30 miles on it so far. This weekend I'll try to get a video of me riding past the camera at full speed, from a stop, and coasting. That should give you an idea of what it sounds like to others as you pass by them. I'll try to do a second video in a month or so if I notice that the sound levels have continued to go down.
 
Yeah, for your use you could certainly get away with overpowering the motor. When i use the term 'continuous', i mean literally running the motor at that power level for 24 hours, IE it will sustain that indefinitely. So there's lots of wiggle room between cooling and heating cycles in the kind of riding you do :)

I'm not familiar with your controller, but if there is a way to tune the phase amps down so that the motor has a really flat response curve, or maybe even a kinda putzy low end torque, creating sort of a mid-high band for the torque ( the opposite of what's native for an electric motor ), then you could probably run that motor reliably for quite a long time, even at the 600w you're thinking.

I did this with my MAC, and that's how i was able to beat the hell out of it for many years... the clutch was never hit with a spike of low end torque.. I dogged the original 500W unit with thick laminations along at 1600w for a long time... and it survived Utah and Colorado's hills!

It would be great to get a video. I'm kinda on the edge of ordering one.. just concerned about the sound, because i was thinking it'd be a great knee rehab / mental health motor for riding in nature with.. but if it sounds like an RC car.. i might ditch the idea and buy it's bigger brother, the bafang G310.
 
Has anyone measured the output wattage at 48v with the stock controller? What is the top speed at 48v with what side wheel? Do they program the controller for max speed based on wheel size? I'm wondering if telling them I'm putting it on a 16" rim then building a 26" would it go faster?
 
BCBeaver said:
Has anyone measured the output wattage at 48v with the stock controller? What is the top speed at 48v with what side wheel? Do they program the controller for max speed based on wheel size? I'm wondering if telling them I'm putting it on a 16" rim then building a 26" would it go faster?

I haven't tested this motor with the stock controller.

In the first post, I mentioned that this motor is available in different gearings. The lower ratio gears will have the motor spinning faster, but at a loss of torque. So, you could get a faster geared motor and put it in a larger wheel, but the bike will require much more help off the line and will get up to speed slower (even though the top speed may be faster).
 
I wanted to update you guys about the motor. I've been running the motor at 48V nominal and 12 Amps for a couple of weeks now. The motor has performed very well at these power levels in a 700c x 25c wheel. My commute is pretty flat though with an total climb height of just 300 feet over the course of my 5 mile commute. There are a couple really steep hills, but they are short and I'm up them in under one minute. Here's my impressions so far:

  • Noise: The noise has gotten better with the motor being about as quiet as a Q100 at this point.
  • Clutch: The clutch is still ridiculously tight. It still is almost as noisy as the motor under power as it is when I'm coasting or riding without assist.The motor does not really freewheel when off the ground. With a firm flick, I'd say it spins maybe 90º before stopping. I plan on opening this motor at some point to get a look at the clutch and see if there's something I can do to improve it.
  • Power: The power is not bad. At full torque throttle (I'm using a Phaserunner controller for those that haven't read the full thread) the motor can accelerate without any assistance nicely on the flats. However it still needs a ton of help starting from a standstill on an uphill slope. There is one steep hill stop I have on my commute where the motor really can't get going without me really putting some heft into the pedals (I'm riding a 46x16 single-speed). Once I have a little forward motion though the motor starts to really pull before I have crossed the intersection—maybe 3 or four pedal strokes. Again, on the flats or only modest hills from a stop this thing pulls right away.
  • Speed: This motor seems to top out at about 28-30 MPH on a fully-charged 48V pack in a 700c wheel. I am confidant that this motor could be run on a 52V (14S) pack if you're not dealing with too many hills to bump that top speed up to about 32-ish MPH.

At this point, the clutch is my biggest complaint about the motor. If I can adjust or change something to make it better, this will be a fantastic motor. At his point I feel its an OK motor, worth the $75 bucks, but the noise and drag are annoying. I would say, if you're up in the air about getting this or a Q100, get the Q100H at it's lowest possible gearing (201 rpm). The two features of this motor that make it better than a Q100 are the lighter weight and the cable that exits inside of the dropouts instead of at the axle end. If those two things are important to you, then get this motor, but know it is not an exact equal replacement to a Q100.
 
I posted in another thread that I burned out my charger connection on the battery, so since the bike is going to be down while I wait for new parts to arrive, I decided I'm going to open the motor up and take a look at the clutch. While I'm at it, if its not too difficult, I'll get a look at the other bits too.

I'm really hoping there's something I can do to improve the clutch. At this point its really the only part of this motor that I don't like.

When I get it back together, I may try cranking the amps up to 15 and see what happens. :twisted:
 
Thanks a lot for the update. Looking forward to seeing it's guts. Pretty impressed that it's taken the power you've given it so far!

My guess is that it's like the MAC.. it can dish out a LOT of power, but at a certain point the heat buildup gets exponential. When you try 15A, take a few hand temp measurements here and there, at least.
 
neptronix said:
Thanks a lot for the update. Looking forward to seeing it's guts. Pretty impressed that it's taken the power you've given it so far!

My guess is that it's like the MAC.. it can dish out a LOT of power, but at a certain point the heat buildup gets exponential. When you try 15A, take a few hand temp measurements here and there, at least.

To clarify, I doubt I'll keep it at 15A unless its an amazing difference in performance. If I can't perceive any increase in heat with my hand, then I'll leave it at 15A as long as it has noticeably improved performance. It there isn't much difference, I'll drop it back down to 12A to improve the life of the motor and battery.

I may not have time to crack the motor open until this weekend, but I'll post pics and impressions as soon as I do.
 
I have a weird feeling you're gonna find that it doesn't have a clutch :O
 
Yeah, and.. it might not be a bad thing if the rolling resistance is tolerable. One less part to break on a motor that is suspiciously cheap to start with :)
It would be the perfect motor for a PAS setup. Also, without a clutch, it can do regen.

Pop that bad boy open and let's see!
 
neptronix said:
I have a weird feeling you're gonna find that it doesn't have a clutch :O

I had never considered that. It would be totally awesome if this little geared hub motor didn't have a clutch. Being able to do regen with the small 13s2p pack I have would be pretty awesome. I'd just have to figure out how I'd implement the trigger to activate regen braking.

Unfortunately, I forgot about a business trip to Palo Alto I have on Monday, so I'm busy getting stuff ready for that. So, I'm not going to have the time to pull the wheel off and attempt opening the motor this weekend. I'll do it when I'm back on Thursday though.
 
zro-1 said:
neptronix said:
I have a weird feeling you're gonna find that it doesn't have a clutch :O

I had never considered that. It would be totally awesome if this little geared hub motor didn't have a clutch. Being able to do regen with the small 13s2p pack I have would be pretty awesome. I'd just have to figure out how I'd implement the trigger to activate regen braking.

Unfortunately, I forgot about a business trip to Palo Alto I have on Monday, so I'm busy getting stuff ready for that. So, I'm not going to have the time to pull the wheel off and attempt opening the motor this weekend. I'll do it when I'm back on Thursday though.

Nah - I asked Xiongda a few months ago, and they sent me details of the internals: they say it's technically not possible to use the motor as dynamo.
 
I contacted them on alibaba and they only offered me a winding that does 28kmh ( 17mph ) for a 700c wheel. No mention of the 12.25:1 version. I had to refer to this thread to find that out.

My plan..

I have a nice roadbike with drop bars and can hit 27mph on a flat pedaling sans motor if there's a slight grade or a tailwind, so i think the 12.25:1 ratio version would be more appropriate for a constant mild boost with PAS. I'm going to keep the phase amp to battery ratio extra gimpy ( maybe 2:1 or less ) so that it only gives me ~100w of boost from a stall and forces me to shift and pedal hard to get up to speed until the midrange kicks in and the wattage climbs to 200, 300, and peak at 350w, as that's what the efficiency curve tells us is the sweet spot for this motor :)

This motor will give WAY more power with the higher reduction ratio on 48v+, but i'm just looking for lightness and the simplicity of running a tiny 10S battery and the lightest hub that money can buy.
 
qwerkus said:
Nah - I asked Xiongda a few months ago, and they sent me details of the internals: they say it's technically not possible to use the motor as dynamo.

Did they provide any images/diagrams/specs that you can share here? That would be very valuable info in this motor thread.
 
Back
Top