Brushless Gearless Hub Motor $110 on Ebay- Thoughts??

[3wheels1life]

Hi everyone,

I found this hub motor on Ebay.. is it any good/worth buying?
http://www.ebay.com/itm/36V-350W-Brushless-Hub-Rear-Wheel-Motor-Electric-Bike-EBike-Bicycle-Conversion-/360667761614
I would appreciate hearing your expertise.

-3wheels1life

 

[spinningmagnets]

Looks like a Conhis?

http://www.conhismotor.com/ProductsList.asp?id=113

 

[3wheels1life]

Thanks spinningmagnets.

To me it looks like this one by conhis. It's missing the plastic end pieces (for the axle) though.

http://www.conhismotor.com/ProductShow.asp?id=84

Is it actually direct drive? Do you know more about it?

Could it support 7 speed freewheel, 1 speed freewheel?
Are the specs the same as those on the above url?

Is it any good (do you have experience with it)?

Thank you.

-3wheels1life

 

[3wheels1life]

Hi everyone,

oops.. that was the wrong link, the ebay item is very similar to this one (see link below)

http://www.conhismotor.com/ProductShow.asp?id=85

But the Ebay hub motor has the flange for the spokes on the side (not one in the middle) and the flange is not cut out like the one at the url above.

Thank you.

-3wheels1life

 

[dogman dan]

It looks like a 400 clyte, but even smaller diameter. A dd motor that small will be handicapped a bit on very steep hills, but it may not be that big a problem depending on what rpm winding they used.

It looks ideal for those who don't climb a mountain, but who's biggest need is stealth. It should run very quiet, with non of the low whirring noise of a gearmotor. Perfect for NYC, or the bike path with a no motors law.

If it is a slow motor, one that goes 15 mph on 36v, you could ride with others on bike paths and they would never notice you were a cheater. You wouldn't be obvious, noisy, or going too fast to be real.

 

[spinningmagnets]

I agree. I recognised it because I had been looking at Conhis motors as a potential mid-drive. By giving the motor some gears to work with, its smaller diameter would not be as much of a handicap. I am happy with the power of a MAC as a mid-drive, but I can't help but to wonder how quiet I can make a mid-drive, and the direct-drive 408/406/etc are no longer available (unless you order large lots, like Justin for his edgerunner).

As a regular E-bike motor the small diameter makes we want to suggest that it would be "adequate" in a 20-inch wheel, but in a 26-inch it would just be inadequate.

 

[dogman dan]

Actually, it's rotor won't be quite as small as in a gearmotor, and if they give it a slower winding, it should still climb hills fine. Especially if you overvolt it . But not the choice for a trail bike needing to tackle extreme grades.

Even if it's comparable in rpm to a 2807 9c, it would still get up a 5% grade with no problems at all. But yes indeed, it would likely run better in a 20" rim. I have to agree, 20" rim on big motors means radial spokes, which I think suck. So a great motor for a folding bike that wants to be quiet.

Looks like a great petite motor to make a mid drive with, as you were thinking.

 

[3wheels1life]

Thank you dogman and spinningmagnets.

Will this motor (on the eBay link) work well (or is the diameter a major problem?) for riding on streets/bike paths?
Also, do you think there will be any problems with it due to this?
How could I test it to make sure it works without a controller (just for short period)? I'll get a controller later.
Are conhis motors good?
Do you know if it will work with 7-speed freewheel from the dimensions given?

Thanks.

-3wheels1life

 

[3wheels1life]

I forgot to ask,

Will it work with 20" or 26" rim?

Thanks.

-3wheels1life

 

[dogman dan]

Send me one, and I'll let you know how good it is. :wink:

290 rpm on 36v. That's medium fast. It will work fine on 26" rim, but would tackle hills much better on 20". Fast enough to run 20", it's not a slow motor.

The dimensions given don't help much, but it should work with a 7 speed. If not, put a single on it. Freewheels are very affordable.

More or less, ALL hubmotors however crappy are suitable for riding the speed you should be going on bike paths and multi use paths.

You can test a newly arrived motor. The ES WIKI should have the halls sensor testing procedure in there someplace. Testing the phases is very easy, if the motor resists rotating really a LOT, the phases are shorted. Beyond extremely unlikely that you would get one shorted out, unless there is obvious damage to the wires as they leave the motor axle.

The first tool an Ebiker needs is a digital voltmeter. The second is a wattmeter, however cheap. The third is a motor/controller/throttle tester. Those are well worth the 30 bucks.

 

[3wheels1life]

Thanks dogman for your advice.

I was planning to use it on a 10-speed 26" bike (5 gears in the casette). I plan to use it on streets/sidewalks/paths.

Will it work well for that in this setup? I'm sure you have more experience than I do with hub motors.
Thank you.

-3wheels1life

 

[3wheels1life]

I ordered one of these the other day, will see how it goes.
Thank you everyone.

-3wheels1life

 

[torker]

The price is right. Let us all know .

 

[3wheels1life]

torker,

I will let you all know on this thread.

Also, how many Ah will be good for a 36v 350w hub motor to last 1 hour? I'd like to get the most cycles out of a lifepo4 (likely ping).

Thank you.

-3wheels1life

 

[dogman dan]

If you run at a rate of 350w, which should get you close to 20 mph, you'd use 350 watt hours in one hour. So buy a battery with 350 usable watt hours.

A 36v 10 ah ping would just do it, but if you want maximum lifespan, then a 15 ah pack would be better for a few reasons. 36v x10 ah = 360 watt hours.

Lower discharge rate, when used at 350w.
Able to handle more than 350w use
If used at 350w for one hour, you'd be using less than 100%. Keeping it closer to 80% depth of discharge helps lifespan. 440 wh. in the 15 ah.

Also, 36v 15 ah is still relatively light and easy to carry. About 11 pounds or so, fits in most bikes frames, or not so bad if carried on a rear rack.

Maximum size you'd consider is 36v 20 ah, or 48v 15 ah, about 700wh. Bigger just gets too cumbersome to carry on most bikes.

 

[3wheels1life]

Thanks dogman.

Here's the details.
I received it and noticed a few things.

It will not accommodate a 5 speed rear freewheel. Even thought the motor is much thinner than the (Raleigh) forks, it would have to be modified (thanks to the design, it is pretty much centered with the same amount of room on both sides). On both sides of the motor, the axle is designed so it cannot be moved sideways (by making the axle thicker than would fit through the dropout as it gets closer to the motor itself). Perhaps it can be modified...
Also, on a Schwinn frame with 125mm spacing it will not fit (though it fits fine on a Raleigh with 135mm spacing). To fit it on the Schwinn, I'd have to widen the forks.
It is heavier than it looks I still have to test it and see how it works.

I'll have to get the wheel built (later).
Do you think a 24 tooth single freewheel would be adequate for using it as a single speed? Or would a 3-speed freewheel be adequate?
As a side note, it does not spin nearly as easy as the regular hub (non-motor). I have to push it a bit to get it to move (though it is not stuck). Would you know if this is geared or gearless (internal) by how hard it is to push?

Thanks so much!

-3wheels1life

 

[Gregor]

Most geared hubs have a freewheel built into them, so they have very low "rolling resistance". Three speed freewheels are fairly easy to find on ebay, but most of them are from china (long wait for shippping). If you can find one locally, take your hub along to make sure it fits before you buy it. If you want to convince yourself that it is direct drive, just short 2 of the 3 phase wires, and the resistance to spinning should be much more difficult. Cheers and good luck.

 

[dogman dan]

Exactly. It looked to me like it was a direct drive. To pedal it easily, but not waste your power, just give it a tiny tickle of throttle. At 50w drain, your battery will last hours, but you can pedal like it's freewheeling.

Or apply 100w of throttle, and get a tiny bit of motor help, and still go a long ways on mostly pedal power.

Yeah, heavy, no avoiding having a big bundle of copper in a powerful motor.

To fit on 125 mm frame, if you can't bend the frame because it's alloy, you might try cutting 5mm off the axle shoulder of each side. Easily done with a simple hacksaw.

Use whatever fits on the freewheel. Most use only the highest gear on an ebike anyway. So nothing really wrong with a single speed. You might be able to get a smaller top gear if you can cram a 3 or 5 speed in there.

Dishing the rim to the left side might make fitting more gears possible.

 

[3wheels1life]

Thank you for replying.

How can I test the phases without a controller (just to make sure it works)?
Is a controller really needed to test it?

Thanks.

-3wheels1life

 

[dogman dan]

Testing phases on a brushless motor is easy. Put the motor in some droputs, or grab the axle with a wrench. Turn the motor, and note the resistance. It's supposed to have a quite noticeable resistance.

Then touch two or more of the big power wires to each other. If the resistance is a lot more, it's because they are now shorted. If the resistance is the same, then the phases were already shorted before.

I never heard of a new motor arriving with shorted phases, unless shipping damaged the wires at the hub causing a short in the wires, not the motor itself. It's just so easy to factory test that, even in china the defects get found.

 

[3wheels1life]

Thank you dogman.

I tested it today. With two of the phase wires touching, it became much harder to turn (*this means the motor and phases are working properly right?* ). Does this mean it is a direct drive and brushless motor?

Thanks for all your advice, your help has been much appreciated!!

-3wheels1life

 

[Gregor]

To answer your earlier ?, yes you do need a controller to test a brushless motor for its actual rotation, watt output, etc. You can use either a sensorless controller in which case you only hook up the main 3 phase wires, or you can get a sensorless controller that uses the 5 hall (smaller) wires also. These can also be fould on ebay,but once again, most of the cheaper ones are from China. You might want to check with the seller of the hub, but if I were you I would get a sensorless controller with an output of about 400 to 500 watts. Cheers...

 

[3wheels1life]

Gregor,
Thanks for the advice. I just bought a 350w controller from eBay. I will let everyone know (on this thread) how well it works when I test it with the motor.
Then, I've got to get the wheel built, etc.

-3wheels1life