DCMotorworks said:
about using the 24v controller at 36v for accessories, from my experience the short answer is no. I used an old dead controller at 36v (it wouldn't power a motor any longer or give warning beeps etc. but it still worked just to run the lights and horn). my findings were: the horn developed problems at 36v. the rear LED light burnt out some resistors and quit working and the headlight melted the plastic reflector after a month or two, diminishing it's beam. DC
I have a stock 24V EVG as well, the controller cannot take more than a peak of 35V, not only because of the caps being 35V but also because the voltage regulators cannot take more, they will die if you try it with a battery that is giving more than 35V. I am running it with 8s LiPoly cells, so the peak voltage that I use is 8 x 4.2 = 33.6V and this is as high as I dare to push the bike.
The only thing that completely died on me is the horn, when I tried using it the sound kept going for much longer, then slowly died with a whiff of smoke.
Later I found out that the relay controlling the horn is too sensitive and wired in a weird way: the current through the light-on LED will always run through the horn relay. If the pack voltage is above 30V then the current is high enough to keep the relay engaged after you release the horn button, so the horn keeps going (and dies) until you switch off your lights....
Also, I lost one row of taillight LEDs. Since it is sealed, I don't know if a resistor died or a LED or a solder joint. It sees quite a bit of shock and vibe because I moved the light from the seat to my rack, which is a one-arm clamped to the seat post. This avoids that I accidentally cover the light with the laptop bag that I often carry.
I plan on upgrading the bike and controller to higher voltage by adding a DC/DC and higher rating MOSFETs and diodes.
At this moment the bike is very usable, but I often pedal faster than the stock motor at 30+Volts can go.