5kW hub drive motor! (Washing machine DIY E-bike)

Vikingimike01

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Jul 1, 2018
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Hello, the bike was ordered, not bought from the shop. I'm angry at them for selling me a set of pedals and then telling me they won't install it... And I don't have the tools, and they are not selling tools like that...

The bike was about 500 USD. I am however planning on replacing them to hydraulic disc brakes, but the back wheel will be that by default, with the kit.

I'll look for a pair of those.

EDIT: The back wheel has a wobble in it! That's why it's so horrible! So does the front wheel! But that one is almost not noticable. But the back wheel, you can notice it at the axle. It will be swapped out anyways but- I'm very mad. And this bike is new!!!
 
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Vikingimike01

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Jul 1, 2018
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Hello! Back. I have everything on the bike fixed, and installed, other than:
Battery, controller, pedal assist sensor, alarm

I have a small problem with the battery. It's very big, oof. It's a 30 Ah 72v pack made from 2 different 15ah 72v packs wired in parallel. It's too big to fit in the frame. I can either put it on top (men's bike) or make like a rack on the back. The controller fits in the frame.

Where do I put it now?
 

bakaneko

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Nov 16, 2015
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glad everything arrived in tacked. If you don't have the tools, I would hold off on the pedal assist sensor for now until you get a sense of how powerful the motor is going to be at the different PAS levels. 5kW rated is what 1kW-2kW-3kW-4kW-5kW levels? I mean I don't know what it might be 1kW is no joke from a dead stop; might be hard to control. For big battery packs I've seen guys just mount it on the top tube on either side. A picture would help to get a sense of things. Also, keep the wires to both packs the same length.
 

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Vikingimike01

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yeah i did that. Anyways. I may have to mount it on the top tube

Its raining a lot here this week so cant really work on it
 

Vikingimike01

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Yes indeed. It has a 120 amp controller. Multiply by 72v nominal voltage, or 84v fully charged, you get wattage. Around 14 horsepower i belive
 

Vikingimike01

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Hey guys! I am having problems.

I set everything up on the bike. It came to installing the batteries. I used 2x 72v battery packs wired in parallel. Okay.
I wired everything up. Plug in the battery, i see huge sparks at the plug, and then hear a huge pop from inside the controller. And it doesn't start, nor do anything. What happened? It's supposed to be a 72v 120amp controller...
 

bakaneko

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Just checking. You double checked the wiring diagram and tested the final battery connectors with a multimeter to confirm the right wiring? Sometimes, the chinese electronics have weird wiring.
 

Vikingimike01

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weird wiring... Ahh i didnt check the battery but it seems to work correctly. Do you want a picture of the wiring? Could I blow the controller by having the negative and positive reversed? Probably didn't do that but still...
 

bakaneko

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Nov 16, 2015
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Do you have a multimeter? This is essential to just ensure everything is correct. I have a lot of wiring on my ebike generator hybrid and before plugging everything in, I test each new connection from the battery/generator sequentially to ensure everything is wired and voltage is correct. I saved myself a few times doing this.
 
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