Introduction: Mobi - a Motobecane Upgrade

About: I am a student in graduate engineering school of computer science and electronics

Hey guys! In this instructable I will show you how to turn an old Moped motorcycle in an electric one !

Step 1: Parts and Inspirations

I wanted to make an electric moped for quite some time now. I used my summer vacation to do so.

Watching a lot of videos of YouTube and from other instructables post about electric bikes, I figured I would need quite a powerful motor and battery to have an enjoyable ride.
I went for a 1000W motor and a DIY 600 W/h battery. In total this built cost me around 200€ for the most necessary parts and 300€ in total.
Here is the main parts I used:
-MY1020 48V 1000W motor with the Kit (150€)

-E-bike Break Levers Kit (10€)

-11 new laptop batteries (4€ each)

-48V battery charger (25€)
The rest is some nuts and bolts, some aluminium plate, duct tape etc.

Step 2: Remove All the Unnecessary Weight/room

In order to have enough room for your electric motor and parts. I removed first the old seat. It's really easy, just like a bicycle one. Then I removed the motor, by taking the axis off the frame.I also removed the old 420 chain and the pedals.
You also need to remove the old throttle and brake levers and add the electric ones.

Step 3: Building the Battery

Since I bought a 48 V 1000W motor, I needed a battery with enough voltage and enough capacity for a trip of about 20-30 km. I went for a Li Ion solution since it's the cheapest. I bought 11 6-cells laptop batteries for 4€ each.
It's made of 13 rows of 5 cells in parallel. In total, it's a 48.1 V battery of 650 W/h.

Step 4: Adding the Motor

Okay, now is the important part!

I first build some kind of wooden plank to bolt the motor to the frame. It needs to be really in the same axes as the wheel sprocket is. Then you need to modify the existing chain, to fit the new length.

Once you have attached the motor controller, you just have to plug everything together.
The new brake lever will stop the motor when slowing down. The throttle is actually a potentiometer to adjust the speed.

I choose a 9 teeth sprocket with a 44 teeth at the back. This gives me a max speed of 53 km/h or 32 mph.


PS: You can say "Hi" to my dog Fidji ^^

Step 5: Adding Some Aluminum Covering

In order to ride safely , I build some battery compartment. I used some 0.5mm aluminum sheet and angles. Just measure the space between the seat and the luggage rack, and trace on the aluminum plate. I used some old inner tube to old the seat.
Finally, I add some of it around the motor.

Step 6: Final Words

This build isn't exactly done yet.

I plan on doing some modifications.
I add a light that I found in a garage sale for 2€.

Right now, I can go at about 50 km/h (30 mph) at full speed, but it doesn't have a huge acceleration.

I'm also planning on developing a android app with the speed and battery percentage, thanks to some arduino, a bluetooth shield and some other stuff. But summer is over, and I need to go back to school...
I'll update thin instructables throughout the months.
If you have any questions, about e-bike, or where to find parts, please feel free to post them in the comments, it will be my pleasure to answer them!

PS: I'll also post a Video asap ! :)

MacGyver Challenge

Participated in the
MacGyver Challenge