Electric Bicycle (Custom Mounting)...
Currie Technologies - Electro Drive...
Spring 2006
This is a
continuation of the "Currie Electro-Drive" kit posted in Sept
of 2005.
The defective
controller took almost 3 months to return from California, but to Currie Tech's
credit they covered the shipping in both directions.
The last weeks of November
were getting too cold to do much riding but I did run a couple charges through
the battery pack and determined that the previous rack assembly was too weak as
it broke twice before the snow started to fly.
The rack pictured
to the left is the proper height for a 26" wheel, but still lacked adequate
hardware to accommodate the sprung rear end.
The assembly is substantially
stiffened by the addition of 2 additional struts of 1/2" by 1/8th"
steel plate arranged in a classic tri-angle config.
The rack can now
take my full bulk of 155lbs of raw bone muscle and sinew without any flex.
All hardware is
either fixed with lock washers or has double nuts cinched tight to resist
loosening from road vibrations.
The original
Currie Tech controller/power pack tended to make the bike marginally unstable
when mounted so high on the back rack. Also making the bike tip over easily when
parked.
The saddle bags
shown to the right were originally intended for use on a skidoo (picked-up on
special for under $15 at Princess Auto).
The bike sat like
this for over 2 days as I considered as many options for mounting as
possible.
Pictured below is
the solution that I finally settled on. The use of wood as a light weight
material was the turning point as I had considered fabricating either fiberglass
or welded steel inserts to give the bags some form and rigidity for mounting.
Again more band
steel is used to tie things together as well as an assortment of nuts and bolts.
Once I was
resolved to this path the hardest part was cutting the first hole in the saddle
bags.
Before it was all
said and done a total of 24 holes ranging from 3/16th" to a gaping 2"
were cut into the bags.
The bags are
secured to the rack with the wire hold-down and 2 heavy rubber bungee's quite
securely.
The nip & tuck
resulted in a fairly rigid assembly that is quite tight to the bike with no
rubbing on the tire or interference with the brakes.
The
controller/battery pack is pictured here.
As stated on the
previous page Currie Tech's design was for mounting on the down-tube of the
bicycle frame (which isn't possible on this bike).
Again giving
Currie Tech a measure of fairness, I deviated from their instructions and may
have contributed to the premature failure of the controller by restricting
air-flow due to mounting the controller on the rear rack.
The guts are
carefully husked from the black ABS housing and laid out for detailed
inspection.
Before getting
into mounting the components into the bags I spent a few minutes tracing the
wiring into the hand scrawled schematic shown below.
Note: the Fan is
an addition that I opted to insert to actively keep the controller cool.
The controller
shown to the right is quite different than what was with the original kit, in
that it has 2 additional IC's and is completely potted in some form of gelatinous
goop.
The potting
material feels cool to the touch and hopefully has adequate thermal transfer
characteristics to keep things cool.
The rating on the
back of the controller is 24Vdc 40Amp Peak/28Amp Nominal, the fuse is also 40Amp.
Given that I've
probably violated any and all warranty coverage by merely opening the
Controller, I opted to cut back the tin shrouding and mounted a 24Vdc fan to continuously
blow directly on to the electronics.
The fan was
scavenged from a large Oki-Data printer and has a current draw of 80ma. Although
I'll be sacrificing almost 2 full watts to active cooling, it will be a small
price to pay if this controller survives the summer.
The mess below is
everything mounted within the left bag (except one of the 12V 12AH batteries and
the charger) which are mounted in the right hand bag.
The controller/fan
are mounted such that fresh air is drawn through a metal mesh guard covering a
2" dia hole through the side of the bag.
The power switch
is covered by the bag when zipped closed but is still able to be turned on or
off easily through the material.
The completed
bike has been out for a quite 2km run through the bush, but there is little to
report as most of the run time was spent walking the bike through 8 to 12"
sections of snow where the sun apparently never shines. But overall the feel of
the bike is much better due to the lower center of gravity and the splitting of
the batteries on either side.
In closing, as the
warmer weather is close at hand I look forward to getting this rig out for more
testing.
As an aside, as I
live in the province of Ontario, where this set-up is explicitly outlawed as
described in the Highway Traffic Act (even to this day)... Like so many others
in Ontario I've written directly to the Ministry of Transport requesting that
they revise the HTA to allow electric Bikes in the province to no avail. It
seems odd that Ontario and one other province are still hold-outs while the rest
of the Canada has made provisions for their use. Though the HTA does make
allowances for me to drive my 6000lb tractor that likely measures almost 30ft
from loader to bucket when the back-hoe is attached without any restraints such
as lic, insc or registration.
For now I'll
resign myself to the seedy under-belly of a criminal life as I skulk about the side roads
silently at 18km/h on the flat stretches and up to 30Km/h down hills pedaling
like a fiend.