by czach » Sun Jun 03, 2012 9:02 pm
So I posted way back in the fall of last year about my Enjoy's controller being dead. Spent the winter fiddling with it, never got it to work. This morning I went out to the shed, looked at the bike all in parts and said to myself:
"It ain't gonna fix itself..."
And got to work.
First was the goal, to get the thing moving again. I decided to go with a simple contactor control with as much safety as possible. Then I could turn on and off the motor while riding as needed.
So. First step was to run new wires from the 24 volt power block the battery sits in to the motor and a contactor. I have an Elec-trak, and a bunchof 36 volt contactors which are perfect for the Aprilia.
Why? Well, they will close on 24 volts. And if voltage drops much below 20 they will cut out. So since the 24 volt pack has a low voltage cutoff of about 20v it's perfect to use as a low voltage cutout. Likewise 14 gauge wire will provide voltage drop from the pack to buffer hard starts on the motor.
Wiring for the motor is simple. Battery positive to contactor, contactor to motor, motor to battery negative. I used bolts and electrical tape so I didn't have to cut the motor wires.
The control circuit for the contactor is a bit more complex: I wanted to turn it on and off from the little speed select switch. And I wanted the motor to shut off if either brake was pulled. And I wanted it to do nothing with the key out. So I put all of these switches and such in series so the control circuit went:
Battery positive (at the contactor stud)-contactor coil-key switch-brake switch-brake switch-black wire for speed control-orange wire for speed control-battery negative.
Then I bolted the contactor to where the old controller screw went into the top body of the Aprilia, put the pack in, turned the key, and hit the switch.
Brief second of power, then nothing. Battery dead from sitting for a year. Charged battery. Tried again, motor spun with no wheels. Realized motor was hooked up backwards. Reversed motor wires, hit the switch.
Bike wheel spun. Hitting either brake would shut the motor off, and stop the bike. Same with the key being off. Safety is not bad.
Took it for a little ride, worked well. Starting it in first gear is best, by second it would tear along. Important to pedal with the motor, get a lot of torque. Then I took it to the park. Worked very well, I would pedal up to speed then let the motor carry the bike for a minute, then switch off and coast. Going up hill was simple with some pedaling assisting the motor. Nice.
Then I hit some debris and the back tire blew out. Great. Rode bike with flat in first gear back to car, end of day.
I'll fiddle with this some more, but I think this is a good start. Yes, I could put in a controller, but I kind of like the "power or no power" simplicity of the contactor. I don't know what kind of shape the battery is in, but it was charging for 3 hours at 3.5a rate, so it's got at least 10.5ah of capacity.
And at least it's working for now. Anyone else done something like this?
Chris