Finally started the batteries

Assembled the first three battery packs.  There will be 20 in total.  Each pack is 30 parallel (all positives connected to all other positives, and all negatives connected to all other negatives) 3.7 volt 2.3ish Ah cells, which makes each pack 3.7volts and about 69 Ah.  When I bolt 20 of these packs together in series (positive buss bars to negative buss bars) the voltage will be 74.  I may add one more pack to get it up to about 78 volts…we’ll see.


The buss bars are made out of 1/4″ copper refrigeration tubing into which I inserted 8 gauge solid copper.  I’m guessing the ampacity of this combo to be between 150 and 170 amps each which would be at least 300 amps total carrying capacity.  The controller is capable of delivering 200 amps continuous, but that’s basically at “wide open throttle”  Most of my driving will be probably less than half of that.

The ladder rungs are 12 ga solid copper, and the teeny tiny fuse wires that go to each cell is 28 ga tinned copper.  These tiny wires should be good up to around ten amps before they melt, which is their intended purpose.  If one cell takes a shit, it will hopefully melt the fuse wire, and save the rest of my pack.  Without fuse wires like this, one bad cell could conceivably destroy the entire pack.

Here’s a closeup showing the fuses:

The negative side looks the same.

The “ladder rungs” bend around the tubing, and I make these really tight on the battery holders.  Then I run a bead of hot glue on the underside.  They seem pretty solid this way.

It’s a lot of soldering, but whatever.  It’s no big deal if you’ve got a modicum of will, and a speck of patience.  I’ve seen guys crying the blues about how much work it is to make these packs.  Only a total pussy would call this work.  I yell at the radio while I’m making them, and the times flies right by.


Gas tank, side panels, ammeter, start switch


Ready to ride?  Not quite, but I’ve made some nifty side panels, cut the bottom of the gas tank out, semi-installed an ammeter, and have the starter relay wired up with a new bar-mounted switch.

I had a latching relay on order last post.  It arrived, and works just fine, but when I looked at the wiring diagram for the relay I could not for the life of me figure out how to reset the relay without the use of multiple switches.  The problem was that in order to reset the relay I had to be able to apply a pulse of electricity with a reverse polarity.  If you’ve ever wired a switch imagine rewiring it so that you can supply both positive and negative from each side.  Once you start thinking about it your conclusion will be the same as mine which was “fuck that.”  I think they make these to receive the reset pulse from a different power source.  Since the ground is always ground, it would require switches on the ground and the positive in order to reverse the polarity.  Fuck all that.  They do make latching relays that have separate terminals for the reset pulse, but I’m a bit tired of ordering relays so I just stuck a simple switch on the bars, and used a normal, high voltage relay that I already had.

Relay is on the left, the flasher relay is the orange one.

Closeup of a side panel that I cut out of some 22ga steel.  They looked stupid as big plain solid sheets of steel so I snazzed them up with the vents.

Here’s the little starter switch I added.  I thought the led might be helpful as the motorcycle is pretty much silent until it gets moving.  You do hear a “click” when the relay activates the main contactor, but that’s about it.


Here’s the ammeter that I stuck where the old filler cap was.  It should tell me the current draw as I’m using it.  Not super-necessary since I’ll have a cycle analyst that should tell me the same thing.  I just thought it might be something neat to fill the hole with. (that’s what she said?)

If I had the batteries all done it’d be rideable right now.  So far I’ve processed about 560 cells.  Of which, about 150ish were fried, and about 50 of my ‘B’ grade cells have been set aside to use as a 12v battery to run everything but the motor.  I’ve got about 360 ready to be assembled into packs, and have more coming in the mail in a few days.  I need 600 for the main pack.  I’ve been processing these during all waking hours for about 2.5 months.  It’s a slow process, but the batteries are a huge expense to buy new.  600 new 2600mah 18650s can be purchased for about $3000 if you can get them for $5 each.  If you get them from used laptop batteries bought via ebay you can get 600 for about $750 to $800 depending on your luck.  The downside is it takes 3 or 4 months to test and sort the 800 you need to get 600 good ones.  Most of that time doesn’t require you to do much.  You just have to keep cycling batteries between charging and testing.

This video outlines the process:

Got the 12 volt system mostly wired.

I nearly have all the 12v stuff done.  I’m really just waiting on a relay that I want to use to turn on the 72 volt contactor.  It’s a special relay called a “latching relay” that uses permanent magnets to keep the switch connected after an intermittent pulse of power is applied.  This way I can use the start button to turn the main contactor on.  If I used a regular relay I’d need a switch.  There is no kill switch on these aftermarket handlebar switches or I’dve just used that.

Relays and contactors are simply switches.  Switches that utilize electromagnets to close a circuit.  The purpose of the smaller, latching relay is to allow normal 12volt switches and wires to power its magnetic coil, closing the circuit that I have connected to the 72volt main contactor.  So a little switch is turning on a big switch, which allows higher voltage and amperage to power the motor.  The 72 volt switches and cables need to carry 72volt, and 200amps continuously, which would totally fry/melt most 12 volt components which usually carry less than 15 amps @12volts.

The 12 volt system is most of the normal motorcycle wiring…horn, headlight, brake light, turn signals, keyswitch, etc.  It sounds simpler than it is though.  For instance, the two left and two right turn signals are switched by a handlebar switch that gets its power delivered through a flasher relay (which basically just turns the power on and off to makes the lights blink).  Simple right?  Right.  Then you have to also connect the four turn signals to the hazard switch.  You can never feed one side off the other, or all blinkies will flash whether you switch left or right.  Then the two rear blinkies need to also be connected to the brake light, which is connected to the front brake lever as well as the rear brake pedal.  Then all the lights also have a running light feed, and maybe some led indicators that tell you if you forgot to turn your blinkies off or if you’re driving around with your high beam on.  Then I’ve got all of this stuff running through a little fuse box, and a main light switch, plus a keyswitch on the bars.  Needless to say it’s a lot of fucking wires, switches, connectors, and soldering.

That, and I’ve not used anything from the original bike.  Well I did salvage the original rear brake switch, which I mounted in a different position.  But all the wires, switches, and connectors are new.


Cut down the brake light, and welded a bracket to mount the license plate in a way that doesn’t mess up my pretty fender.


Headlight, running, and blinker all on at the same time:


Little key switch in a mount I made from a couple of pieces of bar stock welded together.  I decided not to run the spedometer/odometer.  I’ll be using a cycle analyst anyway which makes that blob redundant.:

I still would like to wire some led “dash” indicators, and I need a little light shining on the plate to meet legal requirements.

Next I need to start getting serious about the battery packs…


Starting the electrical

Much of the fun/easy stuff is done, and I’m moving on to the electrical systems.  There are basically two…the 12 volt system (all the lights, ignition, horn, etc.) , and the 72 volt system (the main battery, controller, motor…all the drive stuff).

The systems do connect via the ignition and main contactor, but that’s about it.

I’ll be making a 12 volt battery out of my “b grade” 18650 cells.  This will eliminate the need for a DC to DC convertor.

I made a little compartment out of flattened PVC to house the controller, fuse box, flasher relay, starter relay, and contactor under the seat.  All these components will eventually be hidden by some kind of side cover.

The PVC compartment painted black:


The left side showing the fuse box which has a red LED that lights when a fuse blows:


See the little spring through the hole?  It’s a simple little suspension system I created to ease the vibration of the controller.  Not completely necessary, but I have an aversion to violently shaking delicate circuitry, and because why not add in some unnecessary complexity?


In the picture below you can see the business end of the main contactor, it’s precharge resistor, and the smaller coil suppression diode.  And that thing towards the front of the compartment is the original brake switch that I rigged up in a slightly different position than original with a little bracket I made from a piece of duct strapping (the little silver band with holes in it).



I don’t have the relays in yet.  Maybe tomorrow.  I’ll be sure to post an electrical schematic when I get one done.  As of right now I’m working off of the controller schematic, and a generic flasher/hazard relay schematic, and a few other EV diagrams.

Oh yeah…got all the rear brake bits reassembled and the new chain installed.  Everything is precisely aligned like I knew it would be.


Baked a chocolate cake

Step 1: Make a pan

Step 2: Stick some foam on it


Step 3: sew together a bunch of pleather left over from your daughter’s Cleopatra costume


Got my new rear sprocket in the mail.  50 teeth.  I was stoked to finally get this.  Was going to finally reconnect all the rear brake stuff, and stick the new chain on, but then I saw all kinds of rust on the swingarm, and it’s been freezing, and I’m getting my annual cold.  Got all the bits wirewheeled, and clear coated, and have the swingarm totally ground to metal then repainted, but it’s too cold for my shivering self to muster the will to install it all.


Lots of updates

Chopped the fenders, sanded the shine out of the chrome, then clear coated with engine enamel.  Started prepping the tank to strip that god awful pinky red paint off.  The plan is to leave it bare metal clearcoated.  Front end is looking a little Steve McQueenish.


Also got the front end nearly done.  Brakes are now rebuilt and working great.  Also cleaned up the front wheel and disc.  New braided line to replace the five pounds of connectors originally used.


New tiny headlight to replace the giant heavy original.  Tossed the heavy-ass fork ears that used to mount the old headlight.  Installed motocross rubber fork boots to replace the totally rotten originals.



I’ve fixed up these little headlight brackets I made, and they are now painted black.


Tore off the massive original instrument panel, and replaced it with a tiny little speedo/odometer that has a few little led indicators in it.  It runs off the front wheel just like the original.  I’ll also have a little digital instrument panel called a “cycle analyst” that will help me keep track of my battery charge level as well as current draw, and other stuff.  I might hook it up to my drill or something to see if I can put the original miles on it.  Haven’t decided yet.

Started working on the seat pan.  Most cafe/brat/trackers completely ditch the rear fender, and weld on a rear hoop, but I like the way this chopped fender looks, and where it’s mounted.  The downside is it makes my seat design quite a bit more complicated.  So I’m making a fiberglass pan.

Here’s the seat area after I cut off a shit tonne of tabs, hinges, and a big lock assembly:

Here’s the start of the pan:


Hate to cover up my pretty fender with a big ugly plate.  I might relocate it later to the bottom of one of the shocks.  It’s against the law here to run it vertically, so I don’t know if I’ll want it sticking way out.  Another little plate rule allows me to run this 1974 plate because this bike is technically an antique.  The law says that I can run an original plate like this, but that I have to have the real plate with me.  I can keep it under the seat or something.


New smaller, louder horn:



The motor is mounted

I have the motor in the bike!  Woot!


And the 14 tooth sprocket is installed.

I welded up this work of art to assist the aluminum plate:

You can see it installed here:

And here:

It fits very tightly, and really hugs the motor to the frame.  Combined with the 1/4″ aluminum plate, it’s pretty damn solid.  But anyway…how about that welding?  I’m starting to get my welding legs under me.

I’m still running a battery testing mill in my living room, still tearing all kinds of crap off the bike, and almost have the front end back together.  I just got my new seals, stainless banjo bolts/washers, and stainless hose for the front brake caliper, and will get that rebuilt tomorrow.  I swear I saved 15lbs on all the crap I tore off the front end…I’ll try to remember to stick it all in a box and weigh it  All the bolts holding the disc on the wheel are rusted beyond belief, and I’ve ordered stainless replacements (Home Depot did not have anything I could use).  I want to post a pic, but will wait until it’s more complete.

I’ve also started hashing out a wiring diagram to work from.  It’s a bit of a mash-up of some other electric vehicle diagrams I found.  I’ll post that when I get it done.

I’d also like to set up a complete bench test of all of the major components, but to do that I need to bite the bullet and get a charger.  They are so fucking expensive I will probably wait until after the holidays.

Doing what I can…

…with what I have on hand.

Ideally, restoring, rebuilding or converting a vehicle starts with the essential (motor, drive train, electrical, brakes, etc.) then moves on to cosmetic stuff like making stuff shiny, painting, and style upgrades.  With this project I’m doing what I can with what I have while I wait for stuff to arrive in the mail.

The obvious absentee is the motor.  I’ve created a precise 3d representation of the motor in cardboard, and have a prototype motor mount also made from cardboard.


I’m totally scrapping this design, but the process of aligning everything up and marrying the motor to the frame was totally  worth it.  The string is the exact chainline.  Everything is also plumb vertically to match the rear sprocket.  I have a 1/4″ thick aluminum plate that I will make the motor mount from, but am waiting for the motor to arrive before I cut anything.  The final design will use a lot less material, be mounted on the outside of the top rear mount, and I will not be using the forward mount.  I’ll be welding something across the bottom of the frame, and will mount to it instead.  I’ll also have a strap around the far end of the motor for additional stability.

But I’ve been messing with other stuff while I wait for the motor…

Cleaned up the forks today, but I’m waiting for the new boots to arrive before I can reinstall them.  Before and after…

Cleaned up the rear wheel a couple days ago…

Also in the process of rebuilding the front brake caliper which was totally fucking seized with rust.  It’s a miracle I was able to get the pistons out at all.  Took hours.  I’m waiting for some new seals and pads to the old ones were pretty rotten.

Got in some motocross handlebars, and installed those with new switches (ignition, horn, turn signal, hazard, high/low beam etc.) and the brake fluid reservoir, and lever.  Have not decided what I want to do with the instrument panel, but I will be replacing it.  Waiting for my new twist throttle for the electric motor, and also grips.

I’ve also been continuously fucking with batteries.  Sorting the bad from good, and measuring capacities.  Only when I have that completed can I start assembling them into packs.


I will continue doing what I can until the motor arrives.


Holy shit getting that motor out was a lot of work.  First of all it felt like it weighed 200lbs, but I can’t find the engine specs anywhere online that list the weight.  Second of all, I swear I only had an eighth of an inch on each side of it to wiggle it out.  I only disconnected the bare minimum to get it out.  All the wiring harnesses were still attached, and I didn’t even remove the carbs.  The process was jack, pry, wiggle, jack pry wiggle…for about an hour.

The weight of the electric motor is listed as 39lbs and my estimated battery weight will be around 60lbs for a total of 100lbs.  If I guess that the old motor weighed 150lbs, the battery weighs 10,  3.4 gallons of gas weighs about 20,  and 2.6 quarts of oil weighs about 5 for a total of 185lbs shed.  So the finished bike should be about 85lbs or more lighter than the original.  If I shed 15lbs of fat, that’ll get me a 100lb savings.  I’m not including all the supporting crap, because I’m guessing that the supporting crap for both engines will be approximately the same.

Tore lots of other shit off too as you can see.  The heavy-ass chrome fenders will be going too, but I’m not sure if I will create the replacements out of one of these.  I have to see if anything closer to what I want is available.

The one thing I took careful note of was the precise location of the sprocket.


I took another picture like this measuring horizontally to the edge of a mount welded onto the frame.  I also etched a line on the frame then popped a mark with a cold punch so I’ll know exactly where the ruler was even if I paint it.  The shaft the sprocket was bolted to was hollow, so I found a piece of dowel that was a hair smaller, wrapped it a couple times with tape to fill the hole exactly, and sharpened the dowel in a pencil sharpener to get the precise center, and I lined the end of the ruler up with that before I clamped it.  I did this with the goal of creating a motor mount to locate the electric motor shaft exactly in the same spot as the original.

As I was tearing shit off, I was constantly reminded that old, dirty gasoline engines are fucking gross…filthy, greasy, stinking, and filled with noxious petroleum-based chemicals.  One benefit of electric motors is that they are dry and clean.  Maybe I’ll price out a belt drive system so I won’t have a sticky, filthy chain to deal with.

Hobbies are fun.

Step 3: tear lots of shit off of the bike