Speedo Thoughts

Recently I’ve been planning the final speedo cluster that I’m going to build to replace the original bulky blob of instruments. From what I’ve gathered, the law requires that I have a speedometer, and I don’t see why Cycle Analyst couldn’t handle that part just fine. I’m actually already looking mostly at the CA’s digital speed and almost never glance at the original speedo, even if it works just fine and shows just about the same speed. The CA now handles the trip distances and total travel and it’s very well illuminated and easily visible even in the dark. As the bike has now pretty much “reborn” it doesn’t matter if I’m not anymore logging the old total distance, which had already passed 90K kilometers with gasoline.

Also the law requires that the turn indicators have some sort of instrument panel lights and the high beams should also have one. I’ve bought these 12V led indicator lights with chrome bezels that I was planning on using to do just that. Two green for the turn indicators, a blue one for the high beam and a red one for the solenoid on/off indicator, telling when the bike is “armed and ready”. With these I could create a very minimalistic (and legal) instrument panel with all the info I could ever need. I also have a blue led voltage display that I was thinking of using to show the 12V system voltage, so that I know if there’s something wrong with the 12V battery or the DC/DC. I was thinking of placing the CA on top, 12V display below it and two of the led lights on it’s left side (left turn and power) and two on it’s right side (high beam and right turn). Nice and compact.

I’ve also been wondering what is causing the kinda high-pitched chirping sound from the front of the bike. I had noticed this sound already even when I was still driving with gasoline, and now after the conversion it started the annoy me a lot more, as the bike is otherwise so quiet. The sound was related to speed and I thought it was coming from the brakes. But today when driving to work, I tested to bend the speedo wire cable a little bit and it disappeared. The sound returned after a while and everytime I adjusted the cable while driving I managed to silence it. So the cause for the sound was the spinning speedo cable. Since the cycle analyst uses a separate magnet sensor, I could ditch the whole wire cable. The sound could also be fixed with just a new cable (or lubing the old one), but now I’m not so sure if I’ll ever install the daytona speedometer I had bought, even if it’s pretty. The daytona speedo uses a cable adapter to convert the signal into electric, as it’s also an electric speedometer. But if I’m not looking at it, why bother with the whole cable setup?

Balance Check

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…

Café Racer!

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? ;)