After about 6 months building a motor and a year building controllers (going through 3 different designs) I finally
got to put everything together
To start, this is the victim:
It's a BeOne Team Replic from 2001 which I bought new and has around 40000 km on it (all hand-pedaled).
The motor is going to sit on the luggage rack (made from 15mm square alu tubing):
Drive is to a sprocket in the rear wheel:
I don't have a hall sensored throttle, I'm using a cable operated throttle (from a 3rd brake handle) to a potentiometer:
Power will come from 20s 5Ah Zippy Lipo, guarded by simple beepers:
The controller is a 6 FET 4115 with all 150 V hardware and 20A current sensors. I use a plain metal box
with a u-piece of aluminium for cooling (no cooling paste as dissipation is low, less than 0.5 W per FET)
This by the way is the bottom of the controller circuit board, lots of work !
The controller and batteries go in the triangle of the frame. A sheet of wood will be clamped in, batteries will
be on one side (in a laptop bag), controller on the other side.
With the throttle hooked up:
Last picture: motor is mounted and connected by chain (via chain tensioner) to the rear wheel:
And that's it, my first e-bike build
I haven't tried it out yet 'cause, well, I'm kind of chicken. It's the absolute
opposite of stealth and with the amount of police on the road here I'm sure to get stopped. It's not a question of whether,
just a question of how far I'll get before that happens
There's lots of stuff for them to comment on (no cover on fast
spinning motor, electric connections in motor are bare metal, no lights, front fork is kept from falling out by hose clamps,
thing is driven by long haired hippy scum)...
Technically it's legal though. Power is limited to 500-ish W by setting the battery current to 7A (at 20s lipo, so around 80V).
Using a throttle is legal to 20 kmh, above this (to 25 kmh) the battery current limit is around 2A, so you have to pedal
to go upto 25 because the 150 W from the motor won't get you above 20. At 25 and over the rpm limiter cuts in and
prevents the motor from spinning faster.