Magic Pie in winter

[vectra_marian]

Hello Everybody,

I live in Canada - Ottawa area. I used to ride my bike between home and work every day inclusive in our heavy winters.
One day I was relocated where we do not have showers and due to my skin allergy I cannot ride anymore.
So I would like to be able to have an electrical bike to go to work without pedaling at all (around 20 km on way) and pedaling when I come back.
1. Winters here could be heavy with temperature usually between -10 to -20 Celsius degree and sometimes -30.
So I would like to know if the MP can withstand those temperatures. what about batteries?

2. the city uses a lot of salt to keep the road clear and "damaged" (keep the road damaged was a joke but is true roads are bad). Cars need a good anti-rust treatment. Externally I will clean the wheal and hub motor but can the salty water get inside the hub? Is the hub waterproof enough?

3. I heard the regenerative breaking can damage the batteries so it will better without. Amepbike dropped this feature because of battery failures. So what about MP? I've seen the regenerative breaking is a very advertised feature but can be disabled if I want?

4. What kind a warranty do I get with MP. I did not find too much on the website and it seems a problem from the forum discussion threads.

5. Reading the specs between MP and ProKit it looks Prokit has a better efficiency than MP. It is true less torque where MP is the winner. So which one is better in winter?

Thanks,
Marian


 

[Sundsvall]

Hi Marian, welcome to the forum.

We here in Sweden suffer with the same kind of winter as you. It’s extremely cold and lots of snow up in the north and lots of salty roads down in the southern of Sweden.

1. There shouldn’t be any problem with the motor, but SLA batteries are useless if the temperature droops below -20°C.
2. The motor housing is made of aluminium, which don’t like salt. The hub is not waterproof and there’s probably some parts inside that don’t like the salty water.
3. To adjust the correct regen, start with zero and slowly increase. I haven't got any problems with it.
4. There’s pretty unusual with MP problems, it’s the controller which have an issue.
5  Something to think about with a winter bike is that it will be better in snow with fwd but it will also increase the risk to fall with a more powerful motor.

Peter

[vectra_marian]

Hi Peter,

Thank you for your answers. This is very helpful.
In fact I am balancing with my choice between GM and Ampebike.
Ampebike claims the hub was tested underwater over 6 hours before first water drop gets inside.
Ampebike does not have all the other features as MP or Prokit (regenerative breaks, reprogram the controller, or to accept 48 volts. etc.). They have two options with geared and direct drive and a fancy cylindrical LiPo battery.

Also Ampebike has a wide hub and it looks I need to use another fork if I will buy their kit.
Their controller is a very simple one which shutdown the current when you are in breaking mode.

So Peter, what battery do you use and what is the range that you achieve without pedaling?

Thank you,
Marian

[Sundsvall]

I don’t believe you can put a hub motor underwater without getting the water inside. I have worked with sealing’s several years and there is no absolutely impermeable sealing without a quite large friction. There’re some pretty expensive, and for a hub motor, large mechanical sealing with a carbon joint washer which have a low friction. This kind of sealing’s should never be dry so they are useless on a bike. If there’s a sealing working fine in rotation it won’t work when it stand still and vice versa. I haven’t looked at these motors though, nor have I seen the test so this is just my opinion. My MP haven’t been out in the rain yet but I have a mini-motor which have been in both rain and deep snow with no problem at all.

My MP is supplied with a 48V 15Ah Ping battery. It gives me a non-pedalling ride for about 45 km.

Peter

[Bikemad]

I don’t believe you can put a hub motor underwater without getting the water inside.

Obviously it's been done, but I wonder how they knew when the "first water drop" actually entered the hub? They must have had two illuminated video camera inside the hub during the test to watch for water ingress at both ends of the axle.

Alan
 

[Sundsvall]

For every drop of water to get inside the motor, the same amount of air must exhale. It is possible that the bearing sealing is the important device which means that all hub motors have the same degree of closeness. Even if there were several hours before they got water inside the motor, the bearings don’t like water either and will in the long term give up. I’m not so impressed by these kinds of tests because they are not realistic. A propeller shaft on a boat motor is impermeable but shouldn’t be driven out of the water.

Peter

[Trond]

I live in Oslo, Norway. I got salt in the hub after just 150km last winter. Had to replace bearings in the hub and clean the hub inside. Bought better ball bearings and filled with extra grease. Sealed with cillicon as well. Hope it is sealed well enough now.