New Pie Order Option???

[respawned]

So which option would be faster in top speed, Magic Pie with external controller or 1000 watt 48v motor with same controller?

[Bikemad]

Hi andto the forum.

If you're after speed, the 1000 watt 48v HBS motor should be slightly faster than the existing Magic Pie's using the same external controller, but if you require more torque for improved acceleration and hill climbing, then the Magic Pie might be the better option, even though it is heavier.

I think the speed difference is mainly due to the different number of magnets and poles used in each motor, but the torque is greatly affected by the diameter of the motor. (A larger diameter motor housing should provide more torque)

Alan
 

[respawned]

Thank you Bikemad That makes sense, I plan on running two motors so torque should be enough. There are no restrictions where I live so I was hoping to have something that can get to 50kmph fairly quickly and then maintain that with a bit to spare for hills.

[Bikemad]

I plan on running two motors so torque should be enough. There are no restrictions where I live so I was hoping to have something that can get to 50kmph fairly quickly and then maintain that with a bit to spare for hills.

Wayne had a top speed of around 52km/h (~32mph), but you will need a battery capable of supplying the required Amps, and don't forget that each motor will need to have its own controller.


Check out this post for more details

A large chainwheel would also be a good idea if you want your legs to keep up and provide assistance at that sort of speed!

Alan
 

[respawned]

About two controllers, would I need to install some diodes between the battery and controllers when using regen to prevent current going from controller to controller? Or is that not an issue?

EDIT: Forgot to mention, for battery I'm planning on using lipo with 14S 3P at 15ah, I found some with a 5C max charge rate. Thanks again for your help, I may have another question or two before I buy but I will keep those for a new thread.

[Bikemad]

About two controllers, would I need to install some diodes between the battery and controllers when using regen to prevent current going from controller to controller? Or is that not an issue?

Diodes are not required between the two controllers, as the regen current will usually flow straight to the battery.

If you had separate regen for front and rear, it would be possible for the current being generated by one motor on regen to go directly to the other motor, but only if the throttle was still being operated. Even this scenario would not cause a problem, because the motor being powered would only draw the amount of current that it actually required, and any surplus current being generated by the other motor would still go to the battery.

With the throttle released, no current would flow to either motor during single (or dual) regen operation.

Alan
 

[respawned]

That makes sense, thanks. This project is really getting me excited, cant wait!