Exiting New Things

[cwah]

Aaaah... I wanted to buy it but didn't because I'd use too much power...

But just tell me it has more torque than the BPM and I'll buy 2 of them for a nice dual drive at 3KW

 

[hech]

the xiongda XD (strictly legal, not like badged BPMs) has two internal gears, the higher ratio (8) for climbing hills, the lower ratio (4) for flat roads. Maximum power output is about 500W.Very effective at climbing 10% hills and ideal for light assist.
A rocker switch lets you select low or high gear, or automatic, the controller then decides when.
the supplied controller is rather conservative, rated 15A.
I would like to see it tested with a 20A or 25A sensored controller.

A curious though wimpy hub motor for those more concerned with their assets than their freedom, what point then in upping the amps and going illegitimate.?

 

[patpatbut]

Slightly off topic.

I just found out my SWXB clone is from Xiongda. Of course it is not double speed version but it is still running fine.

Pat

 

[amigafan2003]

100kgs, 10% hill, 25.5km per hour (15mph) requires 880W at the wheels.
The input power (required of the battery) is = 880W / divided by the yield
If you run the motor at 80% efficiency: 1,100W or 40A @ 37V
That XD motor may do it.

A normal motor that can do 15mph with 500w will just create heat when it meets a 10% hill and it'll stall out. This motor can change down a gear to go up the hill and will run efficiently instead of creating heat but still only use 500w - the speed will drop to 8mph or so though. Then when it gets flat again the gears will change up and that 500w will now be used to propel the bike at 15mph.

Just think of it like a normal bike with a normal rider - you don't put out more power when going up a hill - you just change down a gear and go slower, even though your power remains the same. When you get to the flat, you change up and you go faster - even though your power remains the same.

 

[Deleted member 4366]

A curious though wimpy hub motor for those more concerned with their assets than their freedom, what point then in upping the amps and going illegitimate.?

It's not illegitimate to increase the current to a motor. There's no legal limit to the current as long as it's safe and the motor's rated at 250w.

 

[hoppy]

It's not illegitimate to increase the current to a motor. There's no legal limit to the current as long as it's safe and the motor's rated at 250w.

Interesting! So which legal motor can safely take the most amps?

 

[Deleted member 4366]

The "250w" Bafang BPM and CST, the Ezee Mk2 and the Heinzman readily spring to mind.

 

[hoppy]

The "250w" Bafang BPM and CST, the Ezee Mk2 and the Heinzman readily spring to mind.

Could they safely go to say 40 amps at 48 volts legally?

 

[hech]

250w limited means hubs are the limited, lesser option. Putting some gearing in it like this one enables altogether different possibilities, for example getting up steep hills without having to go into psycho-drive!

 

[Deleted member 4366]

Could they safely go to say 40 amps at 48 volts legally?

30 amps and 64v is doable.

 

[cwah]

30 amps and 64v is doable.

Can you try this config on your new motor

 

[Deleted member 4366]

I reckon 20 amps would be about the maximum. i don't know yet whether it goes with a bang when it changes direction going from low speed to high speed mode.

 

[Geebee]

I reckon 20 amps would be about the maximum. i don't know yet whether it goes with a bang when it changes direction going from low speed to high speed mode.

One would hope there would be soft start on change

 

[Deleted member 4366]

Yes, and I'm still hoping to win the lottery. So it looks like we're both optimists.

 

[trex]

I reckon 20 amps would be about the maximum. i don't know yet whether it goes with a bang when it changes direction going from low speed to high speed mode.

the controller powers down before changing direction.

 

[Artstu]

That sounds really bad to me, perhaps it's not as bad as it sounds? I presume there will be quite a loss of momentum each time you pass between gears. But I guess all of this is unknown at this stage.

 

[trex]

it only has two gears, motor only changes down once at the beginning of the hill. No worse than your bike.

 

[drsolly]

That does look very interesting. I'm looking forward to reading your review of it!

 

[1boris]

Have you tested your new 2 speed motor now D8veh?.Is this a chinese copy of the Panasonic hub motor used on KTM erace P?

 

[Deleted member 4366]

Have you tested your new 2 speed motor now D8veh?.Is this a chinese copy of the Panasonic hub motor used on KTM erace P?

Yes, I've tested it. I love it apart from the noise it makes. It sounds a bit crappy, but functionally, it's better than the Panasonic Erace P. The climbing power is immense, especially when you run it at 48v like the Panasonic. I've ordered another five, so there might be one or two going spare for forum members. Get you name down now if you want one.