Replying to this old thread, because it came up when I googled MP5 max amps out of curiosity. Bikemad was completely correct. At the time the thread was written. I bought a MP5 Vector conversion kit from Golden Motors in 2017. Perfect for my first eBike. With a 52V, 26Ah Lithium battery, 80 Amp continuous 100 peak, I could manage 45-48 Kph.
Switching bikes after 2 years, to a MTB with 27.5 inch wheels, I found a decent 27.5 inch rim, made with 36 spoke holes. Tough to find. I removed the Vector, and installed the Grin Baserunner controller/Cycle Analyst combo, and after a massive amount of experimenting, tweaking, and fiddling with various settings, field weakening etc, with no wind, and a long stretch of smooth road, about 50 Kph. No matter what though, there was at most only half of the off the line grunt the Vector delivered.
After getting rid of the Grin SXXtrunner, I replaced it with a Nucular (how it's spelled) I had to wait 9 months for it. I don't like waiting. To me, instant gratification takes far too long. It was worth the wait. Right from the motor, I upgraded the wiring to 10 Ga., which required a slightly bigger wire hole in the Pie. It autoconfigured itself, and at 15% field weakening, it jumps off the line, and hits it's max of 57 Kph, in just under 10 seconds. (faster with other riders, I weigh 300 lbs) With the rear wheel off the ground, spinning freely, it indicates 74 Kph. I use a second throttle on the left bar, and can modulate the regen braking, so precisely, it's rare to use the rear disk. Before, regen was for long downhill runs, if I remembered to use it. I also injected 5 Ml. of ferrofluid into the Pie, and the temps are no higher than before, my max temp on a hot day, less than 90C. And I still have a little headroom with my batts max amps to play with, which is how I came to find this thread.
I have heard rumours that Nucular hopes to establish their headquarters somewhere in Europe, as unfortunately, they currently are in Moscow. Obviously, their production, due firstly to COVID, and now, to the terrible events in Ukraine, is very very slow. Estimated at more than double what I experienced. Even still, they managed to put out an update to the firmware. Unlike Grin, their hardware uses standard protocols like LEVCAN and CANBUS. The display, has levels that you can set brightness on, (the cycle analyst was blinding at night) and even an autodim, that is configurable. And greatly appreciated, since I ride in the winter here in Canada, there is a automatic defroster, on the display. The controller, and onboard computer/display, cost about half of what I spent on the Grin junk.
This is not an ad for them, I really do hope they are able to keep going, but even if they are not, the genie is out of the bottle, and it's clear that it's possible to to get enough performance out of 48V, and a 1000/1500 Watt hub motor now. China will probably have a clone out soon. Or Grin, probably at 4 times the price.
Big thanks to Golden Motors, as they made building my eBike possible, and accessible. After 5+ years, and many thousands of Km, of hard, brutal use, in temps from -20 to +30, the Magic Pie 5 is the last remaining piece of my first ebike. And I don't intend on replacing it. There has been so much growth in the tech in 5 years, I hope it continues. As it is, for the first time since I built my bike, I'm satisfied with it's performance.
