Hi all! I have recently aquired an old 1986 Honda Nighthawk, and I would like to convert it to an electric motorcycle. I have gutted it, and am ready to start buying parts in January, however I am quite overwhelmed. It seems no one has attempted to convert a shaft drive bike, or if they have I can’t seem to find a whole lot of info about it. I do know that the final drive ratio is 3.4:1 I am worried that this will not allow me to reach a top speed of 65 MPH. The requirements for this bike to work as a daily commuter are as follows. It needs to be able to go 30 miles, maintain a speed of 65 for most of it, and climb a moderate hill once. Most of the miles are highway (55 MPH speed limit), and traffic is usually light. Weather is great 99% of the year, and I will most likely not have a place to charge my bike while at work.
Since this bike is shaft drive, it kind of makes it unique and is why I really want to use this frame. I have read a few other conversion sites out there that have a final drive of 6:1, 5.??:1, etc, and they seem to reach 50 MPH or so and unless I am mistaken that is a higher reduction of shaft RPM vs Wheel RPM than what my shaft drive has. I think this means that I will have a slower acceleration, but a higher top speed. Since I am unsure how I will mate the motor to the shaft drive (I was hoping to order a custom mating shaft), I may have to use a gear ratio and chain. This can lower the top speed to allow for more hill climbing power. Not sure what ratio I should shoot for as an overall. Any ideas would be greatly appreciated.
I am also worried about range, and I am not sure I wholly grasp the Ah rating on batteries, other than more is better :D. Again, some kindergarden level eduaction here would be helpfull. I would like very much to try to get into some Lithium Ion battery packs, but the cost is quite high and I do not have a lot of funds. This will be stretched out over quite some time in order to accomodate the pocket book.
I am also finding myself short on some parts, I do not have any instrument cluster, etc. If I want to register this bike, will I have to have the original speedo? I think I fall outside of the original bikes specifications, even though the frame will hopefully not be modified, it will be a new bike entirely. I hope I can register it as such. The california DMV can, and usually is, most perplexing with these matters.
I have been planning on an Advanced Series wound DC motor, but am not sure how to go about selecting the right motor. I would like the Advanced DC X91-4001 motor, but I do not want a double shaft. I am sure they have an option for me, but I am really worried that I will buy a motor that will be underpowered for my application. I want to stay in the 72V range, but I am considering a 96V application as well. The problem is I don’t understand that difference and trade offs involved with that kind of decision. I know enough to understand that the difference is two more batteries I have to cram onto the frame. I have a hard enough time trying to envision six batteries on the frame, though I am positive it can handle that and be pleasing to the eye. I would like to make some custom fiberglass fairings for it to make it look nice and provide some aerodynamic qualities to help it along. I will most likely use the bikini fairing for the front that it came with. Anyhow, so much to think about and worry about. I could really use eveyone’s help and expertise in this!