Chaos - 2007
During the winter months, i removed the dual speed controller and replaced it with a single speed, in order to change between 406 and 409 speeds i installed a 3PDT ( Tripple Pole Double Throw ) relay.
This relay is a " Magnecraft W389CX-13 " , since it requires 24v for the coil, and my battery pack voltage is 72v, i had to install a resistor " Dale RU-25 760 ohm " in series with the On/Off switch on the handlebars
The reason for all this is that i can switch speeds on the fly, without having to look down at the controller to find the switch, and also keep my hands close to the handlebars. I mounted the switch on the same side as the throttle so that i would be forced to let go of the throttle in order to switch, changing speeds while under load would cause arcing in the relay and burn the contacts.
The single speed, 20 amp controller, is half the size of the dual speed, and fit perfectly inside the frame's downtube section, and the relay got sealed in hot-glue to waterproof the connections.
Next was the 72v 8ah Nimh pack.. During the last few rides of the season, i noticed an increase in voltage sag during my ride home from work. A few tests and emails to Justin from Ebikes.ca , and i took the plunge in opening the battery packs to investigate.
Marked with an " X " the bad cell, 0v, i soldered in a new cell to replace it, and since the pack was open and on the bench, i took advantage of this to re-locate half the weight from the rear rack.. into the frame !
I used nylon filament tape to secure the 2 rows of 15 x D 8000mah ( 8 amp/hour ) cells. 30 cells total provide 36v.
Started with a cardboard template and gave that to my friendly neighbor.
Ended up with this metal tray, painted black, lined with crazy carpet plastic material, and hot-glued spacers to provide an air channel..
Mounting a 15 lbs battery pack to an aluminum bicycle frame is nt as easy as it sounds, in fact, it's darn difficult to do without destroying the frame.. so multiple straps and brackets were required. I got my hands on some 3/4" thick nylon cutting board material, this stuff is tough, and you can cut/shape it without any cracking or splitting problems, i sliced a trip with my Jig-Saw, and then using a Dremel rotary tool i made a piece to fit onto the water bottle mounts of the Norco frame.
This setup prevented the box from sliding down or swinging from left to right..
Box 1 complete, now time for the 2nd box..
Again, template, box, paint, insulate, bolt back onto the bike.
Final result :