Magic Pie Edge - overheating

[Thingamajig]

Hi all.

Can anybody tell me if there is some sort of overheat protection on the MP Edge motor?

A few times the motor appears to have overheated while riding in hot climates (Hilly area). Throttle sort of just judders and cuts out randomly after hard use.

This is not a charge issue with the battery pack, as it was fairly full on the two seperate occasions this occured. the screen/lights also stay on when the motor cuts power.

When touching the motor by hand it's almost too hot to to leave my hand on it (Not scientific, I know). Leaving it an hour to cool then riding again seems to resolve the issue. Leading me to think either it's overheating and causing damage, or there's some protection mechanism in place.

Just wanted to clarify as i'm contemplating ferrofluiding the hub if it is a heat issue. (Has anyone else done this?)

In terms of controller settings it is still stock, and I was thinking of upping the amps to it but i'm not sure thats wise now. What sort of amperage is safe for these hubs?

Thanks in advance for any help.

[Bikemad]

The controller on the MP Edge definitely incorporates a temperature safety cutoff function to help protect the controller's electronics from excessive heat.

I have never used ferrofluid, so I don't know how much difference it would make to the controller itself, but it should definitely improve the heat dissipation from the stator and windings assembly.

If the excessive heat is being transferred from the windings to the controller via the stator assembly, then ferrofluid should help to reduce the cutting out, but if the heat is being produced mainly by the controller's MOSFETs, then it may not make much of a noticeable difference.

If the motor casing is getting too hot to hold your hand on it, then the stator assembly will obviously be even hotter inside the motor casing.

Alan
 

[Thingamajig]

Thought i'd come back with an update.

I did use ferrofluid on this hub and it dramatically improved this issue. No more overheating at all.

However it does eat up my battery when really pushed hard in the hilly environments, which is understandable as it's only a 500w capable motor being pushed up incredibly steep hills so wont be as efficient as say a 1000w+ counterpart.

Even so though, adding ferrofluid means it doesn't get anywhere near as hot - in fact im fairly confident I could go up and down these hills all day at no risk of the motor getting to cut out temperatures. (In fact I can often leave my hand on it without burns!)

[Peterh70]

How did you put the ferrofluid in your motor?

[Thingamajig]

How did you put the ferrofluid in your motor?

Removed the side plate, injected a small quantity (5-10ml) of ferrofluid into the magnets.

I've seen on some cheaper hubs people would drill a hole into the sideplates of their hub to save time/effort, which I think is crazy as it'll allow all sorts of debris and crap inside the hub.

Using a large gear puller, it's easy to just "push" the opposing sideplate off a hub motor. A more brutal way would be to hammer the axel against a hard surface but I think thats also a bad idea for obvious reasons.