Making an ebike ?

[alexis57]

Hi guys,

I'm french but for now, I'm living in Japan and because of this, I cannot buy same things as people in america. (within acceptable prices)
I'm interesting about ebike and I looked for informations on internet and I found this forum.

I'd like to make a ebike (I don't know which one yet) but it's only to be able to ride without using pedals. (of course I will)
I was thinking about buying a 1000W hub motor or a kit :
http://fr.aliexpress.com/item/passion-ebike-48V-1000W-bike-bicycle-engine-High-Speed-brushless-gear-Hub-Motor-Rear-wheel/32298441530.html?spm=0.0.0.0.rzZHt9
http://www.leafbike.com/products/diy-bike-conversion-kit/20-inch-electric-hub-motor-kit/newest-20-inch-48v-1000w-electric-bike-kit-front-wheel-918.html

Actually I prefer to buy only the motor and buying controller, battery and charger in another way. Cause my main goal is not only making a ebike but also learning about it.

- My desired max speed would be 50Km/h - 30 MPH
- Cruising speed : why not 20MPH - 30Km/h same as if I'm using pedals
- My body 60-70Kg
- Flat and short hills.

I'll read this forum, it's my main informations source.

About my knowledges : I'm in Japan for 2years in master circuit design (electronics) but I've already got a master in general engineering. I like DIY. I repaired a lot of cars/petrol engines. I really like finding a new project for learning about it. Ebike is this new project

Thanks guys !

 

[contador]

Wellcome,you are in the right place.
If you dont want to pedal ,a direct drive hub motor may fit your needs.
Nine continent or any clone .You are going to want to choose between a faster winding higher rpm
Or a slower one which means more torque.
As for the battery 48volts will give you more speed than 36 volts.
10 ah may be short in the long run,so if you can afford paying a little more
15ah or more should be just fine.

 

[999zip999]

Find an older comoly steel bike. Steel and cheap with room in the triangle for the battery. 21speed for the freewheel of 11t so you can pedal with it. Rim brakes o.k. with good pads and a torque arm so thr axle doesn't twist in the comoly frame. 48v 15ah or better. Plus ect.

 

[d8veh]

What's the law in Japan? I thought that they were limited to 250w, 24 km/h and they can only give power while you pedal, i.e. throttles not allowed.

 

[alexis57]

Thank you very much =)
I want to pedal but I would like to be able to not pedal when I want...
A slower one means ? If slower and more torque (means being easier able to climb hills), it's okay I don't need speed. Just be able to go to 30Km/h without pedaling.

I thought making my own battery (it's not the first time I make something with 18650 but first time with this much power)
48V of course and 10Ah for beginning, it's easier to add another battery if I'll need.

Mmmmh I thought buy this kind of bikes :

There are A LOT, almost only this kind of bikes in Japan !! Maybe I could buy one for really cheap, there are A LOT abandoned / not used.
I could put the battery in the front in the basket!

I'm gonna buy quickly the motor (maybe the kit for beginning), I keep you in touch !

I don't know about the law in Japan but I'm not crazy, my goal is not to do bad things. I am and I will stay a respectful biker.

For the controller, I just can buy a Chinese one ? With a throttle.
http://fr.aliexpress.com/store/product/Greentime-High-Quality-48V-1000W-45Amax-BLDC-motor-speed-controller-Sensor-Sensorless-Electric-Bike-Scooter-Controller/313864_492963725.html?spm=0.0.0.0.1Ylls8

To me, It's just an experimentation then I want the cheapest one just to learn. (I know that some people couldn't understand this)

I don't have any idea about where buying components.. (motor, controller etc...) many many websites don't ship to Japan... Except aliexpress and alibaba.

 

[contador]

Thank you very much =)
I want to pedal but I would like to be able to not pedal when I want...
A slower one means ? If slower and more torque (means being easier able to climb hills), it's okay I don't need speed. Just be able to go to 30Km/h without pedaling.

I thought making my own battery (it's not the first time I make something with 18650 but first time with this much power)
48V of course and 10Ah for beginning, it's easier to add another battery if I'll need.

Mmmmh I thought buy this kind of bikes :

There are A LOT, almost only this kind of bikes in Japan !! Maybe I could buy one for really cheap, there are A LOT abandoned / not used.
I could put the battery in the front in the basket!

I'm gonna buy quickly the motor (maybe the kit for beginning), I keep you in touch !

I don't know about the law in Japan but I'm not crazy, my goal is not to do bad things. I am and I will stay a respectful biker.

For the controller, I just can buy a Chinese one ? With a throttle.
http://fr.aliexpress.com/store/product/Greentime-High-Quality-48V-1000W-45Amax-BLDC-motor-speed-controller-Sensor-Sensorless-Electric-Bike-Scooter-Controller/313864_492963725.html?spm=0.0.0.0.1Ylls8

To me, It's just an experimentation then I want the cheapest one just to learn. (I know that some people couldn't understand this)

I don't have any idea about where buying components.. (motor, controller etc...) many many websites don't ship to Japan... Except aliexpress and alibaba.

Then you are going to find a lot of information here:


http://www.ebikes.ca/

http://em3ev.com/store/


If thats the bike you are going to get,you could consider Lipo batteries as an option,they are cheaper,lighter and smaller in size.But you will need to learn basic care and feeding of Lipos.

On the other hand,try to find a bike with gears, with just one single speed you will find uncomfortable if not impossible to keep pedaling when the motor is turning at certain speed...

Feel free to use the search window above on this page :wink:

 

[alexis57]

Hi !

Ok, I'm almost ready !

I think I'm going to chose LiFePo4 batteries for the stability (and they are less dangerous)
38120 10Ah in 16s1p
or
with 32650 cells

But I'm not sure about the 48V or 36V and 1000W or 500W ...
I don't really need speed but I prefer being able to climb hills than going fast.

1000W 500W :
Is it possible to take a 1000W motor with a 1000W controller but limit the power to 500W ? ( to not stress the batteries ) I think it depends on the controller but wires have a bigger diameter then more less then less efficient..

48V 36V :
I don't really know which one choose.. On youtube I can see people with 36V go to 50Km/h and with 48V too ...

 

[d8veh]

Lifepo4 is very heavy for a lightweight bicycle. I would use a battery with Samsung, Sony or Panasonic 18650 cells, which will be about half the weight.

 

[alexis57]

Lightweight is not compulsory.
Samsung, Sony or Panasonic are really expensive for an "experimental" ebike... I'll see later when I want to make an efficient ebike.
Moreover, they are LiPo ones... I don't want to see my ebike in fire in the middle of Tokyo.

Edit :
Is it LiPo ?? I see 3.6V nominal. But on this post : http://endless-sphere.com/forums/viewtopic.php?t=57291 the guy said "These cells are great for those who want an alternative to lipo with less of a risk for catastrophic fires."

If yes, actually, buying 13 of these just for test the motor and the bike is pretty good. (even if I wont have many kilometers) 20A is enough.

I found VTC5 Sony, for 10Ah (4x 2500mAh) x 13 for 220€ for 13x4=52 pieces it's correct but I'm afraid about the fire...

 

[d8veh]

They're the same cells as what's in your laptop. Do you worry about that catching fire?
You don't have to make your own battery. Most ready-made ebike batteries already have those cells. Easiest is to get a bottle battery that has them.

 

[alexis57]

I don't worry because it's made for it.
Actually, VTC5 aren't make anymore then I'm thinking about 25R or HE2.

Yes, I'm thinking about it too but much more expensive (I'm in Japan and the shipping is really expensive, I'm gonna look for in a real/physical shop here)