So I love my E36, but it always ran hot for me. After blowing a couple of terminal connections, some wires finally melted together, and it shorted out. I had always wanted to make it into a 48 volt, so why not now.
4 new 12v, 12amp batteries fit in perfectly. (I'd like to think that this upgrade was thought of in the design!) I also got a 60 volt controller, figuring that it would be more than enough for a 48 volt system. It also came with it's own throttle, which takes that variable out of it. I took apart the motor, and it was perfectly fine, but hard to reassemble. I'm 99% sure I didn't change the timing, because there were just two round holes for the motor screws (not adjustable, oblong ones). I read on a website, in a few places, that it's usually fine to overvolt a scooter motor 12 volts with no problem. I hooked it all together with new THHN 10 gauge wire, because that's what was coming off of the speed controller. It came out to be a nice, clean job.
I got on it, and it was noticably faster. But after about 100 feet, I smelled something funny... :) It was the motor. I let it cool and then I took one of the batteries out of the series (basically going back down to 36 volt) and it ran great -- exactly the same as stock. Here's where the questions come in:
The stock motor is a MY1020 36v 800W. It's 4 1/4" diameter and about 6" long. I assume just a better MY1020 would be the motor of choice? I've noticed that the 48v 1200watt is discontinued or something, so I found 2 others: a 36v 1000w or a 48v 1000w. A scooter support guy said that the 36v would be better, because it would be overvolted. But now I'm afraid because my 48v system makes very large shocks come out of the stock motor. :) I also read somewhere that the way to make the E36 a little faster is to put in a 600w motor... that goes against normal reasoning, as the 800w is stock. Anyways, I have a good amount of juice going through there. Should I get the 48v 1000w?
Also, how do I figure out how many amps, and peak amps, that are going through the system? Is it the 60v controller that's sending too much juice? I guess I'm unsure if different controllers send different amounts of power. I would think not because when I went down to 36v, the motor was running fine. (I actually took it around the block at top speed, and it was as good as usual. Everything in the system, batteries, controller, switches, were all ice cold, and the battery was only slightly warm).
BTW, I'm into high powered motorcycles and such, so of course I want power and performance to be the driving factor. I truly think there is no such thing as too much power, just as long as you're always in control of it. :) Thanks in advance for any input!!