WELCOME
This website is about removing the speed limitation
on electric bikes. I own an EVO MD-1 bike equipped
with the Shimano STEPS E6000 system. The Shimano
computer is programmed to cut the assistance at 25
or 32 km/h (depending on country). Mine is (was)
limited to 32 km/h. I searched the web to find ways
to remove the speed limit. There are a few
electronic solutions that consist of a battery
powered device that modifies the speed sensor
reading such as the badassbox.
These solutions are however quite expensive.
I decided to build my own version. Since I don't
know much about electronics, I made a mechanical
version that cost less than 5$. The principle is
quite simple and therefore reliable. Being
mechanical, it has the following advantages:
- It is simple.
- It is easy to make and install.
- You don't need to modify the Shimano electronics or open the motor.
- No risk to damage the Shimano electronics.
- It is fail safe.
SHIMANO STEPS SYSTEM
The Shimano system needs to have a speed input to
work properly. If you remove the speed sensor magnet
from the wheel to disable the speed sensor, the
computer will cut the motor assistance. If you
install the speed sensor magnet on the pedal crank
arm, this will reduce the measured speed and could
give you more top speed. However, the Shimano
computer already has a sensor that measures the
crank arm speed. Therefore the computer will
recognized that the wheel speed matches the crank
arm speed and will disable the motor assistance.
CONCEPT
To go faster, you need to modify the speed reading
of the Shimano computer. It could be done by
modifying the wheel diameter in the computer.
However this has been locked by Shimano and requires
a Shimano dealer access. The way around this is to
mount a magnet on a small wheel that will turn
slower than the bike's wheel. The original magnet
that is located in the wheel is moved away but left
on the wheel. So if the system goes wrong, you could
easily move the original magnet back to its place
and continue your ride.