3000W alibaba hub motor good?

[zombiess]

Thanks for sharing the pictures.
You have convinced me not to buy this motor

I am not afraid to gamble on some products, especially ones that are < $600. I had a few motives in purchasing this motor.
1. Find a cheap setup for a bike I want to build based on a Genesis frame, but one with a higher KV than a Cromotor. KV of this is yet to be determined.
2. illustrate some of the issues and risks involved in getting a "good deal" from Alibaba, etc and that the advertised price is not what you pay and how difficult it can be to get exactly what you want.
3. Show that the Cromotor is not from Alibaba for $300, Geryborg has it built to their own spec. Could be from one of the same manufacturers you see online, but the choice of materials is different. There is some truth to you get what you pay for.
4. Sometimes it's fun to try something different. Variety is good and I have two bikes with 9C motors that works awesome!

I am not disappointed with this purchase so far. I will reserve that judgement for when I open it up and make some measurements and try to use it.

With that said, there are good quality motors (some with very high power, not sure where this one ranks yet, but it's no higher than a 5/10 from what I see so far) available from other sources for decent prices, but fitting them into a bicycle frame isn't exactly easy. I'm not sure how difficult this one will prove, but I should be able to use it. If you want to build a custom swing arm, John in CR offers a killer motor for a great price.

If someone does want to buy this same setup, you need to be very specific in what you are asking for. CNEBikes rep on Skype and email had good English and was pretty easy to work with, but there was a lot of back and forth communication to verify I was getting what I wanted. I would estimate I spent about 4 hours communicating with them to get this setup, (They got it mostly correct). Be prepared to wait several weeks for delivery once you pay since they build to spec. The gold rims took more time and so did the 16mm axle. It added about 1.5 weeks to get those options.

For those who want internal pictures, I should be ripping it apart later tonight or this weekend. Hopefully I can upgrade the phase wires. I need to measure the KV of it as well.

 

[Animalector]

Agreed about the back and forth communication I didn't try Skype just stuck with email so things werea bit slow. Some advice, Don't ask more than one question per email otherwise things get missed you will get an answer for one and not another. Still waiting for mine.

 

[zombiess]

Here are the dirty details many of you want.

13.23 KV (RPM/V) Woot! it is a high speed wind, made a mistake and did not have my 3 spd switch connected when I first measured. Disregard if you read my post stating it was 9.67 KV, that was at 66%. Funny what happens when you lay down to go to sleep and realize you measured the phase to phase inductance at 62uH and know for a fact that the KV should be higher than 9.67. This is what nerds think about when they lay awake in bed.
Stator is 40mm
Magnets are 42mm
23 poles
62uH inductance
At 30V it was drawing just over 1.8A no load and with a 22" tire was going 26mph.

Looks to have good copper fill, but I didn't bother counting strands since I'm not that anal, the wiring bundle is actually thicker than the phase wires leading to it. Shame they used such small gauge phase wires, they should be replaced with thicker ones as the motor should be able to produce some decent torque. I might just do that, never a fun process, but thick phase wires, high amps, 22" OD tire and good copper fill = fun motor


Weight with 17" rim is 24lbs, I will be installing some Shinko SR244 tires

Uses the same hall/wiring combo as a 9C to a Lyen controller. You have to be careful when finding the hall / phase combo as there are two false combinations that draw a lot of current, first one I found was backwards so I just swapped two phase and two hall wires and realized it was the same as my 9C setups. Took me all of 2 mins to find a working combination and another 2 to fix it so it ran forward. Always use a current limiting power supply if available and program your controller for very low battery and phase amps when trying to find the right combination!

I removed the junk freewheel, it's not even sealed, get rid of that thing ASAP, it could break your leg when it fails. Only way to get it off was to take off the bearing cover and then use a screw driver to tap the pawl and knock it loose. They did not design it to be removable.

Controller > Phase
B-G
G-B
Y-Y

Controller > Hall
B-G
G-B
Y-Y

Here are the pics of the internals. I ripped it apart for you guys, hope you appreciate the effort. I was curious myself, needed to get the pole count anyways. Opening it was a pain since one of the bolts was stripped from the factory, had to drill it out. What a joy that was, drilling a stainless steel screw, took me 10 mins.



Check out the gap on that magnet... nice!

 

[0gri]

Thanks for your work Zombiess. You have clearly been very busy! The motor does look a little 'thrown together', but aren't most of the Chinese motor products a bit like this (I'm thinking of Justin's old 9C factory visit video!). Overall it doesn't look too bad, at least on screen. Do you think that this could be the basis of a Cromotor? 9C also do a similar motor. I, like many others, am looking for a cheap and powerful wind, which may need some machining (lathe and or mill), to fit into bike for ultralight moped build. What would you recommend? Thanks again for your research work, helping ES members to continue to develop and enjoy the world of e transport.

 

[zombiess]

Thanks for your work Zombiess. You have clearly been very busy! The motor does look a little 'thrown together', but aren't most of the Chinese motor products a bit like this (I'm thinking of Justin's old 9C factory visit video!). Overall it doesn't look too bad, at least on screen. Do you think that this could be the basis of a Cromotor? 9C also do a similar motor. I, like many others, am looking for a cheap and powerful wind, which may need some machining (lathe and or mill), to fit into bike for ultralight moped build. What would you recommend? Thanks again for your research work, helping ES members to continue to develop and enjoy the world of e transport.

Just trying to share some info, I'm still a curious tech guy and try to help others out. Yes I sell Cromotors and Greyborg parts, but I don't see this really effecting my sales because it's not in the same league quality wise and needs some work to see it's full potential. It is a high KV motor which is a good option to have and the reason I purchased it for a specific build. Greyborg does not offer a high KV motor... yet... This motor needs some major work to the phase wires if you want it to handle the current it should be capable of and that's a difficult job for many, but it's certainly a motor that can be hot rodded. It suffers the same issue as the Cromotor with being limited to just a single rear gear, but with the Cromotor that extra space is taken up by 10mm more stator and on this motor the space is just wasted.

I need to see how the wheel aligns in the drop outs and make sure it stays centered, install a disc brake, make sure that will work/clear everything. The work is not done yet. The wheel build is not even close to what I'm use to because I pay Volt Rider's to do my builds, but this appears to be mostly passable as long as it's balanced after the tire is mounted. The rim appears to be slightly oblong as though it's out of round or some spokes are a touch longer than the others, but it will work. Rim is low end but should work fine, much beefier than the typical China ebike bicycle rim.

If you are doing a moped build, talk to John in CR and get a Hub Monster, I do not see this motor being the correct one for your build, this is more bicycle oriented.

This motor is not a basis for a Cromotor, it's just using the typical lamination pattern many motors use. Pretty much none of the parts of this motor are what you will find in a Cromotor. I am happy to see that it has some thin lamination's. I really dislike the way the wiring comes out the axle as I see that being a possible problem, but it is what it is, I've worked with worse.

Maybe tomorrow I'll open it back up and try to dig out the phase wires and add thicker ones. I'm seeing some possible potential here.

 

[0gri]

Thanks for your comprehensive reply Zombiess. I also noticed that the laminations appear quite thin. The 9C version of this motor apparently has a 50mm wide stator, which sounds more like the cromotor (albeit V1 - probably pressed steel armature in stator). I can understand that Greyborg have business interests to protect, but its a bit frustrating when then won't release dimensional drawings of the cromotor. I think that most of the spec. info. on the cromotor has come from your efforts pulling it apart and getting busy with the digital caliper and the camera. Does it look like its possible to turn down the shoulders on this motor to enable it to fit into narrower dropouts? Greyborg don't encourage this with cromotor, but I don't know if that's simply because they don't want us to open it up, or strength/safety issues. Also, does the axle hole look as if fatter phase wires would fit through? I am also frustrated by single speed only. On my current build, I shaved everything down (axles and side cases) to allow for 203mm disc bolted direct to motor cover, and modified a 7 speed cluster for 9 speed indexing (Sheldon Brown - 7 of 9 on 7). I think that these larger (wider) motors could probably handle at least four rear gears with a little careful machining of the cluster. On a slight tangent, I just watched your youtube vid., on a cromotor bmx build. At the start it says the kv for cromotor is something like 18kv, has the motor wind got slower with subsequent production runs? I think I might buy the 9C version of this motor and strip it down to reveal all - Zombiess style! Then members might be in a better position to decide what to invest in. Thanks again for your contributions to the community.

 

[zombiess]

What 9C motor has a 50mm stator? Do you have a link? I'm interested to see it. Pricing? KV? Wattage? Bicycle compatible? I'm starting to think I might be starting to have a ebike motor hoarding problem. I still have a sample "Deep Dish" Greyborg motor that they decided not to carry. Even have it built into a 26" rim. It's the same diameter as a Magic Pie but built with very high quality internals and a 30mm stator. Downside is it too can only use a single speed freewheel because of the way the wire exits on the freewheel side.

Greyborg doesn't care if you open the motor, or make a technical drawing yourself.
The video of my on my full suspension "BMX aka kids MTB" is my high speed Cromotor, 18KV. Only 2 of them were ever made and I had one reserved because I needed a very hard to drive motor to test controllers with. Most what I have learned on the Xie Chang controllers has been done with this motor. It's harder on a controller than a Crystalyte 5302, a lot harder; but I haven't had any issues getting controllers I have built working on it. These will most likely never be available to the public, at least not in this 18 KV speed, it's too fast and current hungry for anything but a really small tire as you saw in the video, 18" OD tire on a 14" MC rim.

I'm usually as cheap as the day is long when it comes to my own stuff (just look at my high speed kids MTB you saw in the video), but have moved up to higher quality parts in the last year because they have a better Price/Performance value. I just recently spent $200 for a Chris King headset to be installed on my Greyborg Warp frame, could have gone to a Cane Creek for around $160 but decided I wanted the best for my demo bike and never have to worry about it.

Greyborg has more stuff to come in the future...

 

[0gri]

I thought that might get your attention! Note this is all info. from Sunnychen at 9C, and I'm suffering the usual problems getting straight, consistent and relevant answers (no disrespect intended - but clearly language/translation issues). He also seems to have gone quiet since requesting low Customs Declaration value, unless its due to the Chinese holidays. He says the motor is 12x5 wind (not sure how to interpret this - poles x no. of turns/pole?), 3000w, ISO disc compatible, calculated approx. 12kV at max. efficiency of 87%. US$240 ea. (MOQ 5). Also available Sabvoton controller (I think that this is the relatively new programmable sinewave device), rated for 48-72v, 3000W (Price of controller is either US$260 or US$180 depending on which message I read!). Picture of spec. sheet attached. Need to reduce resolution of motor image in order to upload. What do you think? In fact this is an open discussion, what do we all think?

 

[0gri]

Here's the photo of the hubbie. Is the axle on yours (Zombiess' - Nicole motor) held with a key and keyway? Removeable? What about on the cromotor?

 

[John in CR]

Ogri,

That's a scooter hubbie and no way to fit it directly to a bicycle frame without serious mods to both. Once you get away from bicycle motors then the options for big power open up. You need motor specifics to make much of an evaluation. Stator width and number of laminations is a good start. BTW, the Kv comes right from the test report and is 13.7rpm/volt, and I doubt seriously that it's a 5 turn motor as the 12x5 (12 strands by 5 turns per tooth) would indicate. That's roughly the Kv of a 5 turn 9C with a 30mm stator, so 50mm will be significantly slower.

My knee jerk reaction is that motor doesn't have the thin laminations like Zombiess motor that's the topic of the thread. I used well built 40mm motors with a Kv of 16 for years, but they had the 2 per mm laminations and thinner is better, especially for higher power and higher speeds. That's because the iron losses will be lower and once you get into high power and speed, efficiency becomes critical if you want to keep the motor sealed up. That's because higher speed inherently requires higher power. That in turn creates more heat without higher efficiency. Without increasing the size of the exterior shell, you're stuck only being able to dissipate the same amount of heat at the same temps.

Unfortunately the design and construction of hubbies is still dominated by people without real understanding of heat transfer. I run my motors many times their rated power, and have no fear of getting on the highway and doing high speeds for long distances, but that's only because I accept the compromise of opening my motors to the elements to increase heat transfer by an even greater margin than I increase power giving me a cooler motor than stock at stock power. OTOH, hubmotor manufacturers generally haven't caught on to some very easy ways to double the heat transfer rate. Combine that with picking up a few points of efficiency with better laminating steel, and suddenly a 3kw motor can become a 5-6kw motor, while keeping it sealed and highly water resistant. It's time for the ME's, actually the ME's for whom Thermo Dynamics class was fun and interesting (a narrow cross section), to step in and help the guys who have the rest of the motor design work down pat. Better hubbies are needed and wanted.

Personally, I believe a better starting point is with those having stators in the 265mm diameter range. I ran one at staggering torque and power, but low quality laminations really limited that motor. Larger diameter offers more surface area for cooling and more torque for the same force at the magnetic gap.

John

 

[zombiess]

Here's the photo of the hubbie. Is the axle on yours (Zombiess' - Nicole motor) held with a key and keyway? Removeable? What about on the cromotor?

Not sure about the keyway. I almost went down the road of buying from Sunny Chen or Kenny, but I did a lot of research and did not hear anything confidence inspiring. Then a few months later Greyborg showed up and sparked my interest in taking the risk. If you want to purchase, make sure you do your due diligenge. Even Greyborg had issues with one of their orders where the company made the motors with the wrong axles which forced Greyborg to manufacture and replace 100 axles at their own cost.

I am not saying don't bring another motor to market, just be careful and know there are pit falls. Read my thread on the several thousand dollars of Hygia brakes I purchased and how that has turned out... Hint, I lost all my money because the brakes are defective.

 

[0gri]

Thanks for your reply Zombiess, and all contributions welcome John, but you're preaching to the converted. I'm a Natural Sciences major, and 20yr physics professional, so the basics are not new to me, I'm simply trying to get to grips with Chinese marketing. There seems to be alot of secrecy surrounding who can source what, when, how, whereas I'm more inclined to take the Zombiess or Methods approach with an Open Source mentality. Most people on ES will have access to local machining or friends who have the necessary facilities, so modifications are not usually problematic. They just require a little thought. As Animalector put it at the head of this thread, we want good value good quality equipment without paying too much, or too many middlemen. We all have something to contribute, regardless of background and experience. Anyway, back on topic - Sunnychen 50mm stator, 160mm axle shoulders, or Nicole 40mm stator, 142mm axle shoulders? Both are described as 3000W. Neither are intended for cycle use, but looks like both could be! And what about the Sabvoton controller anybody used one?

 

[zombiess]

If you intend to do business with Asia you REALLY need to learn how business works there, especially China. If you don't they will take your money and run a gang bang style anal sex train on you. Sorry, but that crude analogy it's the only way I know how to get the point across. I try to avoid dealing with China too much directly as I have heard many countless horror stories in person from people who have worked with manufactures there in many different businesses. You need to learn how to communicate on their level, the language barrier is a very real hurdle and even if you can get past that hurdle, you will still have to make sure they don't start substituting parts on you, or "improving" the design, etc.

I'm not saying all Chinese businesses are like this, but it is a fairly standard MO and once your money is gone and you receive a product, consider the transaction final, even if you did not get what you specified or it doesn't work as advertised.

I strongly suggest that if you want to go down this route you set aside $5-10k USD that you can afford to lose and try a small sample order, but even that does not guarantee your large order will be exactly as you specified, seen that many times.

 

[0gri]

I get your point Zombiess, albeit slightly off topic! I was lead to believe that 9C were a reputable business. Justin has been working with them for years. I would have thought that the relatively unknown companies were the ones to be wary of. If purchases are made through Paypal are they not protected? I have had many small purchases from China, and a few bigger ones eg. Ping and Keywin. I'm yet to get stiffed, although I appreciate, there's always a first time. As you said earlier, due diligence is a must. Can we get back to the thread topic and discuss these two products? What's the axle in the CNE motor and the cromotor like? Do you have an overall diameter measurement of both too?

 

[zombiess]

Axles are both 16x1mm threads with 10mm flats. I have posted detailed measurements of the Cromotor at www.greyborgusa.com. I have not measured the length. Hope that helps. If you want to order one read all my posts in this thread, you must ask for specific options to get them. I spent a lot of time through email and Skype communicating with CNE. I will be dropping off the motor to have a tire mounted later today or tomorrow. I am curious to see how it performs and find any mounting issues. I am unsure of the axle steel quality, but all my setups use really good torque arms on both sides which don't allow any play. It's probably why I have never had an axle issue even though I am extremely abusive on parts. I have to be abusive because I would rather have something fail on me then resell stuff and have it fail on customers.

Sadly while gaining the info I posted here I really did a number on my lower back so its not doing so well right now.

I do believe this could be a decent motor and I am thinking of importing a few after doing some testing. I want to talk to Greyborg about other motor options first as I much prefer to give my money to them because its much much lower risk and I know I get high quality goods. They are a middle man and so am I, but I see huge value in working with Greyborg over dealing with the manufacturer. I try to add value to the motors I sell by providing detailed specs, solutions to problems such as designing and manufacturing c washers and supporting the product. Almost all of the detailed info on the Cromotors that is posted has come from me. I also work very closely with Greyborg and provide them feed back. Do not discount all middlemen as we are not all the same.

Another thing with this biz is do not expect to make a killing in profits, at least not flow quite a while. This is the first year I should be turning profit and I have sold 100 motors, controllers and other Ebike stuff since I started last year. I do this because its fun and justifies me playing around with expensive Ebikes. I also believe electric is the future and is better for many. When this stops being fun for me I will quit.

9c is a large company, but I know Methods and Justin have had issues with them. I won't go into details as it is not my story, but if I was you I would contact them and ask what business with them was like. That is what I did and I decided to not risk it.

Good luck what ever you decide to do. I will help with any info I have, but truthfully most of it is already posted on here since I am not a secretive person. Info helps others and I like to help if I can, it is why I belong to this forum. Very few of my posts are about selling stuff. I love the tech section.

 

[0gri]

Thanks for your input Zombiess, I appreciate your collective approach. I've been re-reading some of the threads from 2011/2012 to which you have made excellent contributions. I am hoping that we haven't totally hijacked Animalector's thread, and hope he chimes back in when his motor arrives. I haven't yet decided who/what to deal with, but I think I'll send my wonga to whoever appears to be most convincing regarding both product and assistance. Speaking of which, it looks like I might need one of your throttle tamers, unless I can reverse engineer it from your posts! Is the microcontroller code open source?

 

[Animalector]

I'm not expecting much different from ZombieSS motor as they should be the same. I guess I'll find out, mine are cross-laced, not radial, but I got a 19" MC rim not 17, so that would be the difference.

Hopefully today
Andy

 

[sacko]

Thanks for the updates, much appreciated.

Is the plastic 'cushion' necessary? I don't see the need for it.

 

[zombiess]

Thanks for the updates, much appreciated.

Is the plastic 'cushion' necessary? I don't see the need for it.

I don't know, but its sexy so I left it after I opened up the slot some mor for the wire to pass through. The 2 biggest fails I see on this motor so far are the wires exiting on the axle flat making mounting more difficult and the phase wire being the same size as what comes on a 9c motor. Thin phase wires kill most of this motors potential to be decent. It needs the same size as the cromotor. If I ever stop being lazy I will cut them off and replace the through axle wires with some bigger Teflon coated wires I cut off somewhere. I need to stop being lazy though and that isn't looking so good right now.

 

[Animalector]

It's arrived. ... ARRIVED....
Quick unboxing and it is as per the photos i received.

Tires are pretty cheap long but hey something to start with boxing was excellent.

Andy

 

[John in CR]

It's arrived. ... ARRIVED....
Quick unboxing and it is as per the photos i received.

Tires are pretty cheap long but hey something to start with boxing was excellent.

Andy

If you pop the cover, please let us know if there's a gap in one of the magnets like with Zombiess. That's a serious and to me, unforgivable issue.

 

[zombiess]

If you pop the cover, please let us know if there's a gap in one of the magnets like with Zombiess. That's a serious and to me, unforgivable issue.

Come on John, don't you realize this is a high quality motor :lol: it is about what I expected it to be. The gap in the magnets is a big dissapointment because I know it will effect overall performance to some level. No 9C or Cromotor I have ever opened up has had any gap between the magnets.

 

[t3sla]

The gap is to aid in cooling

 

[Hyena]

Nope, they're just at the forefront of fashion :lol:

BTW, I have tested a similar motor and found it to be marginally better than a crystalyte H40 which I guess is exactly what you'd expect given it's construction and spec. The stock wiring as stated is a bit poor but the big axle and bearings allow for easy upgrades to a bigger gauge.
The needlessly wide axle spacing makes it difficult to fit to most bikes though. For sub 5000w applications I think I'd recommend the H40 as an easier fitment option.

 

[sacko]

What are the likely effects of having the gap in the magnets?