BBS02 750w all weather Iceland noob help, first Build thread

[birtingur]

Hello all

Myfriend and i are building a pair of ebikes from the Bafang middrive kit. I have been reading on the internet for a while and ordered some parts and finally everything has arrived. Here I will document our progress. This is my first build.

This is my bike, Vulcan Carrera. Rather inexpensive hardtail. I have an extra pair of rims with studded tires for the snow and Ice.

Bafang BBS02 750W kit bought from Paul at em3ev.com

It will have a 48V11.6A downtube mounted battery I bought from bmsbattery.com which has the panasonic NCR18650PF cells. I have a plan of sewing some waterproof insulating bag to put over it for the winter rides. I think the heat generated from the internal resistance could be enough to keep it warm in the winter when insulated.

One problem I have are the connections on the battery. I don't know how to connect this to the motor. I have soldered low current connections before. But do I solder the big fat wires to this, or do I try to stick them in the connections and clamp it together?

Another problem I have are the chainstays on the bike are a bit too fat so a part of the motor touches them before it can lock around the BB shell. I am thinking about using a large washer around the bottom bracket on the drive side to move the motor unit around 2mm out. That should give a little bit of clearance. Does anybody have a better idea.


Any help or suggestions would be appreciated.

 

[d8veh]

You can use a spacer from a hollowtech BB.
http://www.ebay.co.uk/sch/i.html?_from=R40&_trksid=p2050601.m570.l1313.TR2.TRC1.A0.H0.Xbottom+bracket+spacer&_nkw=bottom+bracket+spacer&_sacat=0

If there's not room to put the second locknut on the other side, leave it off and wire or Loctite the other one.

 

[Samd]

I can send you a spacer if you like, I have them in the for sale thread. A smaller chainwheel might suit snow climbs anyhow.

Food for thought.

 

[birtingur]

Thanks for the tips. I didn't realize you could find specific bb spacers. But anyway, I found a spacer that works yesterday in my granddads garage after checking all the hardware stores in Iceland.

Now I just need to figure out how to connect the battery.

 

[birtingur]

Ok so I got help from someone who knows electricity. This setup allows me to easily disconnect the battery bracket and add more wires later (for lights and stuff)

It has been difficult to get the motor into the bottom bracket shell on my friends bike so we have been carefully filing the inside of the shell to get it to fit.