Today was the day I took the first test drive! And oh boy it’s so smooth to drive… Feels like a much lighter bike than it previously did (it should as it has lost quite a lot of weight), and the throttle was smooth as butter. Amps were set to only 30% of the full controller power and the “throttle up rate” was also toned down, so it ramped up amps gradually. Everything seems to work great and there was no odd behaviour. I think I can now say with confidence that the conversion was a success! Next up: inspection… After that: “beauty pass”.
The batteries are now in place and everything works! The battery case structure seems really sturdy and I think it’ll do great. Only because it was in the middle of the night (literally) and I was dead tired, I decided against taking a small test drive with the bike. I really need to go through everything I’ve done (tighten any loose bolts and zip-tie wires etc) in daylight and figure out some sort of proper mounting for the DC-DC converter (which in the picture sits on top of the bike for the time being). With the batteries in place the converter doesn’t fit anymore below the gas tank. There’s enough room behind the upper box but I need to mount it there somehow. I might drill some holes to upper battery box (batteries removed) so that I can mount it on it’s side. I’m thinking of drilling the sloped corner areas in the top box as there’s room for bolt ends inside and I can first bolt some sort of a mounting plate there where I can bolt the converter on to. But in the long run I might actually consider a more expensive but a lot smaller converter to replace this bulky chinese one…
Finally! This saturday I took my bike on a trailer to the welder (Stadin Metalli) so that we could make the battery box connection tabs that can be attached to the frame. We didn’t have time to finish the boxes on saturday, but yesterday I got the finished boxes. Thanks Sami! They are both made from pretty thick (4mm) aluminum sheet and seem to be a really tough construction. (They look like they could withstand a nuclear war.) The lower box will be bolted to the original engine mounting points with 10mm threaded rods and the upper box is bolted to the lower box with 10mm bolts. The lower box also has a tab that is bolted to the motor adapter plate. This is mainly to support the motor plate to the boxes (not the other way around) and should make sure that the motor mount is stable. There are also some additional tabs on the upper box that will be used to mount the fiberglass fairings (still to be done) to cover these clunky things from prying eyes. And the upper box will have a fiberglass cover that will be latched on top of it.
Late yesterday evening I drilled some holes to act as cable conduits and cut them open upwards. Then I used steel wool to roughen all the surfaces for painting, washed them dust-free and then layered the black primer paint in several passes. This morning I went to see how they were, and as they looked really great, I layered the final glossy black paint on top of the primer. And this evening I will cut an adhesive rubber mat that will isolate the lower compartment battery poles from touching the upper box and will make sure there won’t be any kind of possibilities for any other unwanted “special effects”.
I’m hoping the boxes will be dry enough this evening so that I can finally start placing the batteries inside the bike. And maybe even take a first test drive! (We’ll see.)
Yesterday I finished up some final cleanup and tried to figure out why the 12V battery had drained dead while the bike had sat there for couple of days. I suspect the DC-DC as everything else is key-switched (the converter has key signal switch too and should be shut down, but who knows)… I’ve now isolated even the 12V negative side from the DC-DC with a relay when the bike is shut down. And I’ve also added a physical battery cut-off switch for the 12V system, at least until I can be sure there’s nothing there draining the battery, when everything should be shut down.
I also got the aluminum battery boxes and test fitted them in the frame. Tomorrow I’ll transport the bike to the welder so we can create the attachment tabs so that they can be bolted down. They’re welded from 4mm aluminum so they should be pretty bomb-proof. Hoping to be able to make some test driving tomorrow… We’ll see.
And today I called to the inspection office and talked with the technician about the inspection. Hopefully this will be pretty straight-forward and the bike will become street legal (if nothing profound needs to be corrected). Then the real fun begins…
Yesterday I reached a major milestone. With the help of my sister’s husband, we changed the rear sprocket, cleaned up the rear wheel hub and installed the new chain. And before that I had finally finished up the wiring and gotten the motor running. I brought the batteries besides the bike so that we could test the motor spinning the wheel. Now the bike is pretty much ready for road once I can get the batteries mounted up!
As some extra good news, I contacted another welding company and they should be able to do the aluminum battery cases during the next week. I think I’ll chill out before that and concentrate on my family for the time being. Finishing touches can wait until I get the cases.
Bad things first. The battery boxes aren’t still ready. They were supposed to be ready last thursday and I had planned to take my bike to the welder so that we would have fitted the attachment points to the boxes. The welding company doing the boxes has been way too busy with other deals, as they’ve had people sick and “more important” customers in line. Yeah, life is like that… I know. (But it’s still annoying as hell.)
But on my personal front I’ve been busy fighting my own battles. During the last friday, weekend and yesterday evening, I’ve built a sort of “motherboard” for the bike where I’ve bolted down the major components, installed it into the bike and started wiring things together. Yesterday I got 95% finished with that. Only a little bit of finishing and double (and triple) checking all the connections, and I should be ready for the first test spin of the motor. Tomorrow I should be installing the chain and the new rear sprocket, so that we could see the wheel spinning too. Only if I could get the battery boxes as soon as possible, and I could actually be driving it for the first time…
Above: Tentacle monster, waiting to be installed into the bike!
I decided to ditch the previous battery isolation switch and bought a sturdier one, with easier structure to be bolted on to the “motherboard”. Kudos to Jarkko for tipping me about it. Below are some pics of the progress. Kinda feels the same as assembling a computer… (The whole mess of wires will be hidden below the seat and gas tank, as well as behind the side panels. And the loose wires will be zipped down tight.)
During the last weekend I plugged in the isolated DC-DC converter to my test bench and it seems to be doing it’s job, which is supplying 13.5 volts for the 12V system. The 13.5V is a similar voltage as the gas engine’s alternator used to provide and is suitable for charging the battery. The converter is installed parallel with a small 3Ah gel battery that I’m going to use to replace the original large flooded lead acid battery in the bike. The DC-DC will charge the battery and supply the main power to the 12V system. The battery is there just to supply the key-switch power and to share the load in event of energy spikes or when the drivetrain battery voltage is too low and DC-DC decides to turn itself off. I think I’ll eventually install a 12V lithium battery in it’s place, as this tiny gel battery was just a spare I had bought for other purposes. The DC-DC uses the drive system’s 72 volts as the keyswitch current and it shuts itself when the bike is powered down.
Below is the final EV system setup before I dismantled it for the purpose of installing the components to the bike. I’ve now also installed the 6A reverse protection diode between the fuse box (in the middle) and the key switch relay. The DC-DC is the black box in the right bottom corner. I think I will add one more relay for the contactor/solenoid, so that when the on/off kill-switch in the handle bar is turned off the contactor will be shut down, but the lights and everything else in the bike will stay on. (The notification LED will also be moved in parallel with contactor relay, indicating the status of the contactor.)
I also managed to wire the bike’s original electrics back on, so that the headlight, tail light, speedo lighting and turn signals all started working again, using just the battery. And I’ve now pretty much removed all the components related to the gasoline engine, except for some wires and connectors (which shall stay there until some day when I’ll completely rewire the whole bike for this much simpler setup).
Below is my temporary setup before the future reworking of the whole instrument cluster and installing the café style handle bar (will be done only after the registration). The Cycle Analyst is now where I can see it. It will eventually end up to replace the old speedo cluster, combined with the 60mm chrome daytona speedometer. The Magura Twist Throttle has been installed along with a separate on/off kill switch. I still need to figure out how I will mount the CA speed sensor, as the magnet is made for spoked wheels. Jarkko seems to have mounted his into the break disc holes of his kWsaki, but mine has no such holes to mount it into. But maybe I’ll figure out something… We shall see.
And here’s the motor installed in place. Feels pretty sturdy, even without the third mounting point, which will be supported to the battery boxes. I think the current mounting points are already enough to support the motor, but the third point is there just to provide additional stability. From the looks of it, this motor seems like a perfect fit for this frame. The right side is in perfect line with the body and nothing sticks out. And with the threaded bolt setup, I can fine tune the exact chain alignment with just a couple of bolts. What I have also done is that I have removed the old battery rack and have started figuring out how I will mount the electronics onboard. I think at first I will mount most of them where the old battery used to be, between the fiberglass side panels, below the seat. There they will be pretty well protected from the rain and dirt. As I examined the gas tank (now empty), I think that by cutting it’s bottom I can eventually fit most of the electronics inside the tank. But that will wait (just a precaution) until I’ve successfully registered the bike as an electric motorcycle. That would actually be the first and only thing I’ve had to cut, as I’ve managed to do the entire conversion so far without any modifications to original components. And I’m a bit hesitant to do anything like that until this conversion has been proven rock solid.