I got interviewed by Motouutiset.fi, a finnish motorcycle web-magazine and they published an article about my little project. You can read it here. I’ve been told that google translate does a “decent” job, for those of you non-finnish speakers. Personally I couldn’t have hoped for a better writeup. So I really want to thank Motouutiset and Erkki for writing such a great article.
Here’s some helmet cam recording of my today’s drive to work with my motorcycle. Recorded with Contour+2 camera. I started recording at Myyrmäki-halli (Vantaa, Finland) and ended up at my work adress in Espoo. The camera seems to pick up wind noise pretty loud and you can barely hear the chain noise (which is more audible to ears). Also there was some corrupt sections that I had to cut. And I chopped it a lot shorter (the whole trip is about 20 minutes).
Not so wonderful weather this time… 5 degrees Celsius and my fingers froze. Brrr…
A co-worker of mine took a short “take-off” video, before I rode back home from work. (Wonderful weather to take a bit longer detour through the local fields.)
On Saturday I visited the motorcycle expo and oh boy there were nice bikes. I really liked some of the custom bikes. And I got to sit on Brammo Enertia (commuter) and Empulse TTX (race bike). But I like mine more. ;-)
I have now driven more than 300km with the conversion and charged the battery pack nine times from about 1/3rd left. Everything seems to work real smooth. So I decided to check the cell voltages for any oddities, as I am relying only on bottom-balancing and there is no battery management system (BMS) used in my bike. As I went through them, every single cell of the 25 cells reported values within 0.01V from each other after driving to work and using almost 30Ah of energy. All the cells had values of 3.27-3.28V using the meter that gives a bit higher numbers than the other one I’ve used. So I’d say the pack is still in excellent balance, and there shouldn’t be no bad cells in the pack. I’d say I am now very confident with the bottom-balancing method. Also while opening the battery boxes for the inspection I added some extra insulation in the bottom pack, to make sure that the cells won’t bounce around and that the poles will have zero chance of hitting the bottom of the top box, which could potentially short circuit them.
Everything else went just fine, but as I worked in a rush, I managed to drop the DC-DC converter (stupid me) as I had to disconnect it so that I could get the upper battery box lifted. And I forgot to check it’s operation after the work was done. This morning I tested the 12V voltage and it looks like that I’ve either broken the DC-DC or disconnected some wire (also a very likely scenario) when I put the bike back together. The small lead-gel battery reads only 12.2 volts and the voltages do not jump back up to 13.5V as they used to do when the DC-DC worked and the bike was turned on. I’ll need to debug it this evening… Sigh.
EDIT (23pm): Just a disconnected wire. Failed crimping. Fixed…
Finally had an evening to work with the bike, so that I could install the new cafe racer seat and the led flashers. And I’m loving it! I had earlier began to doubt if the new handlebar wasn’t such a good idea, as after a few days to work my back started to hurt. I wasn’t feeling that comfortable… But now with the much lower cafe seat I’m sitting much more upright again, and it feels really great. Didn’t stretch the back and neck as much. Also what’s nice is that with the new seat I can reach the ground with my both feet, heels on the ground. Didn’t like sitting as high as earlier. I might consider some day also upgrading to shorter rear shocks so that I can lower myself just a little bit more (maybe by 2-3cm). But I’m not sure if I want to mess with the driving geometry, as now the bike feels quite perfect. Honda had it “just right” the day they made this bike.
As I installed the new seat I had to create some sort of mount for the license plate. I took a bit of aluminum, cut it into shape and drilled some holes and bolted it on the small license plate holder that came with the seat. Still a bit rough, but I’ll finish it later on and I’ll paint it black. Also placed an adhesive reflector above the license plate, as our law requires to have one, even if I don’t see the point (the led tail lights are pretty bright). I’m planning on taping it below the seat, just above the license plate. Now “it’s just there”.
Kinda feels like the handling has just improved again a little bit. And not sure if this has anything to do with the mods, but this morning I made a new record low in energy consumption when getting to work, as I only used 52Wh/km even if I didn’t spare in acceleration. But I’ve lost some weight too. So maybe that really did help… The bike does feel lighter, but I think that’s mostly due to better seating position.
Took a while to figure out the wiring for the tail led lights, as they had both the tail/brake lights and turn signals integrated into one unit. They are really great quality, with solid chrome plated aluminum bodies. They weren’t cheap, but man are they pretty… Although I still need to figure out how I’ll remove the old flasher mount supports that are wrapped around the forks. I’m afraid I’ll need to remove the forks so that I can do that. That’ll have to wait until the bike is stored for winter. Then I’ll rebuild the whole instrument cluster and install new headlight mounts. Now the headlight is sitting too high, which looks a bit “goofy” to me.
Something I also did was that I wired the new handlebar on/off switch as a safety feature, which controls the power for solenoid through a relay. It will shut down the motor, but keeps everything else powered on.
PS. I know it doesn’t “do the ton” (reach 100mph), which the “true” cafe racers require from their bikes. If I switched to different sprocket ratio it could possibly reach it, at the cost of low end acceleration and energy consumption. But this bike is geared for city use, not to break speed limits. So I might never test it out. But hey, we’re in Europe. So why 100kph wouldn’t be enough? ;)
Last weekend was just way too busy, so I didn’t have time to install the new cafe seat and the chrome led turn signal lights, but yesterday evening I had at least a couple hours to work on the bike. I managed to fabricate a mount for the Cycle Analyst sensor magnet and to install the new handle bar with the bar end mirror. I found the wheel diameter (2082mm) and entered that to the CA setup. The magnet now works and the readings from the Cycle Analyst seem to be valid. I also installed a new handlebar on/off kill switch (previous one was glitchy and wasn’t used at all) but haven’t yet wired it. I’m going to wire it directly to the relay that is handling the solenoid control power, so the controller etc. will stay on, and this kill switch will disable only the throttle/motor.
I raised the bar a little bit with some riser bits that I had bought so that I could get a more comfortable riding position with the new handlebar. The new handlebar is a bit more “sporty” and narrow than the original one. But I think I like how it feels now. I didn’t want to go “full cafe”, which is usually way lower. That would kill my back. This new bar makes the handling a bit more steady at higher speeds (less leverage). But it’s still nimble enough at crawling speed. I also love the new bar end mirror. It gives me a perfect vision behind me and to my left side. Way better than the originals.
But now I really want to install the new headlight mounts so that I can lower the headlight. It will give the bike a bit more aggressive look. And the old speedo cluster looks like a huge blob with the new handlebar. But that will have to wait. I think I’ll work on that during the winter when the driving season is over. I expect that in about a month it will be too cold to drive. If not sooner…
So far I’ve driven about 200km with the converted bike and everything is working real great. And today was the fourth day that I came to work with the bike. All the readings so far have told me that the energy consumption has been approx. 60-63Wh/km when I’m back home (total of 35km round trip). This morning CA told me I had used only 55Wh/km on my way to work, with an average speed of 44km/h (the speed limits are 50-80km/h and there are several lights where I need to stop). So I am more than satisfied so far. With this kind of driving (typical in the area where I live) the range of the full pack should reach about 50 kilometers. Total pack energy of 3200Wh divided by usage of less than 65Wh/km makes about 50km. Each day when I’m back home from work, I’ve used about 2000-2200Wh and about 28-30Ah. The pack voltage has leveled off just below 80 volts (a bit less than 3.2V per cell) after the 35km trip, so it would seem that there really is still a considerable amount (more than 10Ah) of juice left, as there should be.