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Re:BYD has reportedly received 10 GWh of orders from Tesla f... by sudosysgen on Thursday October 21, 2021 @10:25PM (#28953104)
I have KunTeng controller and disply, with a GS Motor hub drive, pushing 2.5kW peak right now with a 1.5kWh battery pack.

The motor itself is capable of 6kW+peak power with a bit of statorade, but my battery and controller aren't up to snuff

I'm personally pushing 60kph :) But it's pretty scary at those speeds even with the best tires I could find and pretty good disc brakes, so I'm generally at 20mph or under.

I'm planning a 4kWh battery eventually... but not yet.

It's a super budget build for now - a BTwin Rockrider 520 with a battery from salvaged modem packs and an overvolted KunTeng controller and a hub motor. It's super fun though and I've done over a 1000km on it which is very nice.

Re:BYD has reportedly received 10 GWh of orders from Tesla f... by jacquesm on Thursday October 21, 2021 @10:31PM (#28953138)
That's one very mean bike. I think I have enough steel in one leg to keep me off rides like that but consider me impressed that you are taking that into traffic. Is this street legal where you live? You'll be doing wheelies if you are not careful :)

How much does the whole thing weigh? Mine is at 29 Kg, and that's with only a 500Wh pack, I figure about 6 Kg/KWh so by the time I'm done building the new pack it will be around 40 Kg in total or so.

Re:BYD has reportedly received 10 GWh of orders from Tesla f... by sudosysgen on Thursday October 21, 2021 @10:42PM (#28953193)
Well, any bike will do wheelies if you have the knack for it :) But if you're wondering, no it doesn't do power wheelies - I can definitely feel the weight shifting back though.

I haven't weighed it yet, but:

The bike itself is 15kg. The battery weights 48g per cell, so at 140 cells (14s10p) that would be 6.7kg, but I'll round up to 7.5kg for the wiring, mounting, etc...

The motor and controller and screen are around 11kg or so. The hub motor is very very heavy!

Summing it all up it's around 35kg. Sounds about right from hauling it around.

It's not technically street legal, no. But I'm far from the worst offender - a lot of people ride what's basically a 125cc with a hub motor on the end, and they're sold everywhere, so I'm never going to get in trouble for it.

Re:BYD has reportedly received 10 GWh of orders from Tesla f... by jacquesm on Thursday October 21, 2021 @11:03PM (#28953294)
Very neat, and nice to have a fairly high voltage setup like that, mine is only 36V nominal so it needs pretty fat wiring to not lose a bunch of power on the way to the motor (that was the first thing I fixed, the difference was noticable, both in range and in power).

35 Kg is doable, as long as that battery doesn't run dry!

Mine really isn't pleasant if you end up without assist, it's doable but I really hate it, especially uphill. Can't wait until I have that pack ready, but I'm not going to hurry it, I'd hate for it to fail halfway or so, and that's a lot of tinkering to be done still (and a lot of welds...). But the batteries are already here, the balancer as well, I have a BMS from a scrapped pack and a good idea of what the housing should look like, if my test pack works I'm off to the races, then it is mostly straight up assembly and otherwise I'll need to re-think the way the BMS is hooked up.

Re:BYD has reportedly received 10 GWh of orders from Tesla f... by sudosysgen on Thursday October 21, 2021 @11:34PM (#28953464)
I've actually pedaled without the battery but with the motor in place.

Let me tell you, the added weight is nothing... On a hub motor when you don't have a connected battery, say because the BMS tripped as you ran dry, the motor converts a signficant amount of your kinetic energy into electrical energy and then to heat. You can really feel it cogging. I could swear the two weeks I ran it without a batteris saw my thighs get significantly bigger!

Thankfully in my city there are plentiful subway stations with elevators, so when I did run dry once, I was able to pedal my bike into the subway and take it home.

Re:BYD has reportedly received 10 GWh of orders from Tesla f... by jacquesm on Thursday October 21, 2021 @11:44PM (#28953531)
You've found a nice way to add a workout I think :) Mine is simply un-driveable for any distance without support, it's not a hub motor but a mid motor and there is a whole pile of gears that are driven as well as the motor itself. It's like trying to sail with the anchor out.