It seems that my KP-E charger had started to malfunction and didn’t charge my batteries completely. After the faulty charger had completed, the voltage was showing about 81.5V in Cycle Analyst, instead of the 82.1V that it used to, when the charger was still working properly (the CA has always shown lower values than my multimeter and 82.1V in CA while bike is powered on equals about 84V in my multimeter when it’s powered down). I had also measured the cells and they all showed steady voltages, so I didn’t suspect it would be because of a bad cell, jumping too high earlier than the others, cutting off the charge. Actually the charger was my suspect #1, since earlier in the summer it had blown some blue smoke with a loud “pop” once when I had connected power to it. But it had started to charge – and visually it was doing it’s job. So I kept using it. But I should have been more suspicious since the voltages weren’t what they should have been.
And since the pack wasn’t charging full anymore, one day when I was driving back home from work, the voltages started dropping really fast and the pack was showing near empty. I had barely driven 25Ah and it should have still had plenty of power (batteries are rated for 40Ah). Luckily there was just enough juice to get home, but when I got there all the cells were just below 3 volts (near empty), except for one that had dropped to about 2 volts. I immediately charged this cell higher with my Ultramat RC charger (in the picture) and it bounced up back real nice. I balance charged it couple times, matching the other cells at about 3 volts.
Rebalancing a cell
Yay! Voltages looking good!
Luckily Jarkko was able to provide me with a new charger, as his own KP-E was laying around unused. And it seems his charger did the trick and charged the pack full. So I owe him my gratitude for getting up and running so fast again. After the first charge with Jarkko’s charger, the pack showed steady 82.1V again, even after couple days of being idle.
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.
It’s been pouring cats and dogs lately, so during this rainy midsummer weekend I finally added some extra protection to front and bottom of the battery/motor compartment to prevent water and other crap splashing into battery cases and the motor. I used some 3mm plastic sheet, fixed with rubber-padded clamps to the tubular frame. It didn’t rain in the morning, but it had rained whole yesterday and all night and there were lots of puddles here and there. And the motor was completely dry once I got to work. So it seems to do it’s job just fine. Next I’ll be adding the side fairings, which will add some extra protection, especially on rainy days.
What I also did was that I added a proper bottom plate for the 12V battery, under the empty gas tank. So it’s much better secured there now. Also in my (never-ending) to-do-list there’s adding some protection for the front sprocket as a chain guard of sorts. And I’ve got a new shiny headlight that I’d like to install as well.
Luckily I’ve got only this week left at work. Then it’s seven weeks of holidays for me… Oh yeah! (Maybe some time to work with the bike too.)
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.)
Well, I had no luck with the Daytona’s proximity sensor either. It seems that the same problem persisted no matter what sensor type I used. The magnetic field from the electric motor messed up with the speedometer itself. So I decided to remove it altogether and just installed another mechanical cable driven speedometer that I had in store as a backup. Looks and works just fine, even if the chinese “quality” is evident from the text (rmp instead of rpm). Also installed a new speedo cable as the old one was pretty worn out from the hub connection end.
With the new speedometer
Still haven’t had the time to do anything else, like installing the new fairings. Hoping to do it as soon as possible… I’ve also received my new shiny Japanese-built headlight with chrome-plated metal housing, which is a little bit smaller than the current banged & scrached up original one. Going to look purdy, for sure.
Yesterday I made an base for the “idiot lights” and CycleAnalyst from aluminum sheet. There’s green leds for the turn signals, one blue for the hi-beam and one red for the main contactor on/off switch, which will be on when the throttle is operational. Now the instrumentation should meet the requirements of the law. I’ve also ordered an optical sensor for the Daytona Speedo (which at the moment is detached). But the Daytona is now only “nice to have”, since I’ve got all the information I need in this setup (even speed). It will add some “prettyness” though.