Front Hub DD motor identification.

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Brodie   10 µW

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Front Hub DD motor identification.

Post by Brodie » Jul 26 2021 4:38am

Hi everyone, new member here. I have been lurking and soaking up a lot of information before beginning my bike build. I am at the point now where I have ordered the battery, controller and nessecary attachments.

I was give an old 36v ebike with a front hub DD motor.
The battery was an old prismatic cell type that wouldn't charge higher than 33v.
So after a bit of reading on here I decided to move to a 48v system.
I have bought a 48v 15ah 30a continuous output battery, a KT 18Fet 45A sine wave and a KT LCD8H.
The plan is to run the controller at the half setting for a max output of 26a at 52v which is what I can figure a max charge 48v battery is.
But overkill on the controller but it won't have direct airflow where I was planning on mounting it so thought the bigger size might be better.

As for the motor. I am having trouble identifying it and need some help. From what I have read it should be ok to take the 1.3kw max that will get pushed through it.
Hopefully one of the experienced members here can tell me what I have via these photos.
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Cheers, Brodie.

LewTwo   100 kW

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Re: Front Hub DD motor identification.

Post by LewTwo » Jul 26 2021 4:52am

A DD Hub with radial lacing on a springer fork.
By any chance is that a "chopper" or "low rider" bike ?
The more I learn the more obvious the immensity of my ignorance becomes.
Weight Wennie E-Bike https://endless-sphere.com/forums/viewt ... 3#p1173723
Shaft Drive Grocery Getter https://endless-sphere.com/forums/viewt ... =6&t=90718
...and thanks to Justin!

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Brodie   10 µW

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Re: Front Hub DD motor identification.

Post by Brodie » Jul 26 2021 6:51am

Not quite my style.
The original bike the setup was on was a Giant Boulder 3.
I come from a motorcycle background and see this project as a good chance to build something closer to the start of the motorcycle but with different propulsion.
I am building a custom frame based off an old ladies road bike.
The motor is currently off to be respoked.
IMG20210606113710.jpg
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Still very much a work in progress. I have just bulked up the fork dropouts to be 8mm wide. Hopefully they will handle the power.
Still need to weld in a mid tube to mount the battery and controller to.

LewTwo   100 kW

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Re: Front Hub DD motor identification.

Post by LewTwo » Jul 26 2021 8:49am

Brodie wrote:
Jul 26 2021 6:51am
I have just bulked up the fork dropouts to be 8mm wide. Hopefully they will handle the power.
That could not hurt.
Might want to consider "bulking up" the pivot point as well.
The more I learn the more obvious the immensity of my ignorance becomes.
Weight Wennie E-Bike https://endless-sphere.com/forums/viewt ... 3#p1173723
Shaft Drive Grocery Getter https://endless-sphere.com/forums/viewt ... =6&t=90718
...and thanks to Justin!

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Brodie   10 µW

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Re: Front Hub DD motor identification.

Post by Brodie » Jul 26 2021 7:45pm

Not a bad idea, Thank you. Perhaps some tube welded into the fork uprights will help strengthen this area.
Having a closer look at my controller it would seem that the 45A is a peak power level.
It is rated at 22A continuous.
Does anyone have any experience with KT controllers and know if the setting to turn down the power works off the peak or the rated current?

LewTwo   100 kW

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Re: Front Hub DD motor identification.

Post by LewTwo » Jul 26 2021 9:14pm

Latest Chinese firmware strategy is to ignore that particular parameter. They are routing the "throttle" through the PAS system (even if the PAS hardware is NOT installed). The PAS system 'automatically' determines the required amperage. The only way to control the power levels is setting the PAS level.
The more I learn the more obvious the immensity of my ignorance becomes.
Weight Wennie E-Bike https://endless-sphere.com/forums/viewt ... 3#p1173723
Shaft Drive Grocery Getter https://endless-sphere.com/forums/viewt ... =6&t=90718
...and thanks to Justin!

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E-HP   100 MW

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Re: Front Hub DD motor identification.

Post by E-HP » Jul 26 2021 9:46pm

If you run a front hub, will that suspension design tend to lower the front end during acceleration? Not that it's good or bad, I just haven't seen a project using a front hub motor using that style springer fork before.

markz   100 GW

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Re: Front Hub DD motor identification.

Post by markz » Jul 26 2021 11:14pm

48v 15ah 30a continuous output battery, a KT 18Fet 45A sine wave and a KT LCD8H.
Your controller will ask for 45A but your battery can only put out 30A so your battery should have a BMS and that BMS will be kicking in, working the BMS board in the expensive battery rather then working the cheap generic controller.
Better setup would be a 45A battery 35A controller.

The springer forks arent a quality product so it will be interesting to see how long it lasts before it breaks. Hopefully you wont be going fast on that ebike, hate to see the fork collapse.

I have a front hub motor, rigid fork fat bike with 52V 40A & 36V ??A batteries with 35A controller, and the forks pulling 350lbs.

Don't forget about your torque arms.

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Brodie   10 µW

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Re: Front Hub DD motor identification.

Post by Brodie » Jul 27 2021 1:17am

So with the controller being a 45a max 22a continuous and the KT LCD8H letting me limit the max output using the c5 setting I thought I should be able to run this controller without issues.
If so the C5 setting of 04 divides the max output by 1.5.
45a÷1.5=30a. Provided the controller functions as it should I had thought the battery would be adequate at this C5 setting.

Has anyone seen this motor before or have any information about it that may help with my build?

I expect the forks to compress the spring as the motor takes off. This will lower the front as the rake increases. Not the best suspension method but I have a few smaller OD springs which I can fit inside the stock spring to help with this if needed.

markz   100 GW

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Re: Front Hub DD motor identification.

Post by markz » Jul 27 2021 2:44am

Limiting the power would be good. I do generic controllers, throttle only, no pas but I like cruise control because then I dont have to pedal to get power, just rest the forearms on the handlebar for more aerodynamics and get some extra mileage out of the batteries watt-hours.

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Brodie   10 µW

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Re: Front Hub DD motor identification.

Post by Brodie » Jul 29 2021 2:21am

Does anyone recognise the symbols that are on the inside of the motor?
The two outside ones I have managed to translate but the middle symbol is unknown. I am assuming it is a logo of some kind.

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