# Bafang - What Were You Thinking?



## Old & Slow (May 3, 2020)

As a first time mid-motor installer, I read numerous posts and watched YouTube videos. So most of the process was expected challenges, however their were the unexpected as well. Chief among the unexpected was the battery-motor interface. I was expecting a simple quick connect because I'd purchased the motor and battery in a package deal.

Here's the initial battery and motor leads:








The battery has an XT60 male, while the motor has an Anderson color coded connector. Why, I asked, after all these years haven't the motor and battery manufactures agreed on a common connector?

Included in my kit was this monstrous interconnect solution to mate the Anderson to XT60:








You can see it's just shy of 4-feet long:









Why wasn't a simple short interconnect provided, given that there is no agreed on common connector? Found a 4-inch solution on Amazon:
https://smile.amazon.com/gp/product/B08GPXTY8H/ref=ppx_yo_dt_b_asin_title_o00_s00?ie=UTF8&psc=1
And an even shorter solution on eBay for $1 more.

Why did Bafang decide to bring the motor wires out the bottom instead of the top??? In harms way?








That single wire going over my BB is to the speed sensor, to short to reach going between BB and motor. That and the universal SS magnet wouldn't fit my flat spokes. So I kludged this until I can acquire a better magnet.









Not all bad, I was told to expect, in the manual, that with my 73mm BB that the lock ring wouldn't fit. Perfect fit:








I suspect that Bafang made a running change to the BB shaft length to accommodate 73mm BBs. I added the nuts you see so I could tighten the Y bracket to the motor housing w/o bending the bracket.

Another pleasant surprise was the 42T narrow-wide chainring:









Even with this absurd chainline going to my 9-speed cassette, I have yet to have the chain derail:









So adding the plusses and minuses, I'm probably ahead. Finished install:


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## PierreR (May 17, 2012)

There should have been two 5mm shims in your kit to accommodate the 73 mm bottom bracket shell to non drive motor mount. 

Why can't you mount your speed sensor out where the spokes are mostly round? 

As far as the incorrect lead connectors goes the importer should have corrected that for you or asked you which kind you wanted. Most people shorten the leads anyway so soldering is necessary. 

Bafang totally has their head of their ass on the chainring deal for sure. 

Wires out the bottom is because the Bafang units are only water resistant, not water proof. You have to do some mods and smear some bear sht to make them water proof. You get water inside one of them and they will do all sorts of funny things depending on where the water is.


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## Old & Slow (May 3, 2020)

PierreR said:


> There should have been two 5mm shims in your kit to accommodate the 73 mm bottom bracket shell to non drive motor mount.


Cool! Likely I overlooked those, will have to check.



> Why can't you mount your speed sensor out where the spokes are mostly round?


Tried that. The aluminum spokes are too fat in the round portion for that magnet. Will also lengthen the sensor wire so I can route it between the motor and BB.



> As far as the incorrect lead connectors goes the importer should have corrected that for you or asked you which kind you wanted. Most people shorten the leads anyway so soldering is necessary.


I've got 5 pairs of XT60's on order for a winter project. So the Amazon adapter is to get me to winter.



> Wires out the bottom is because the Bafang units are only water resistant, not water proof. You have to do some mods and smear some bear sht to make them water proof. You get water inside one of them and they will do all sorts of funny things depending on where the water is.


Sound like the bottom wires are a drain. Another winter to do. May have to come back to this for ideas on where to apply bear sht. Not now.

Do you know anything about the walk control? I see the walk symbol, but as soon as I release the button (-?) it goes back to PAS. Ended up setting PAS 1 and using the throttle.

Thank you so much. I've learned so much from reading your post.


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## blcman (Feb 1, 2007)

The walk mode is accessed by pressing and holding the negative button. It takes about 1 to 2 seconds to start working. It's very slow so I did as you have done and programed PAS 1 to a low value (1 I believe) and use the throttle also.
Also if that chainline doesn't work out for you I would advise getting a Lekkie ring (19 mm offset) or the Luna Eclipse ring (21 mm offset). I think yours is about 9 mm offset. You just have to make sure there room on the chainstay for that much offset. I had to do some grinding on mine to make it work.


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## Old & Slow (May 3, 2020)

blcman said:


> The walk mode is accessed by pressing and holding the negative button. It takes about 1 to 2 seconds to start working. It's very slow so I did as you have done and programed PAS 1 to a low value (1 I believe) and use the throttle also.
> Also if that chainline doesn't work out for you I would advise getting a Lekkie ring (19 mm offset) or the Luna Eclipse ring (21 mm offset). I think yours is about 9 mm offset. You just have to make sure there room on the chainstay for that much offset. I had to do some grinding on mine to make it work.


Thanks for those offset number . . . another winter project.


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## PierreR (May 17, 2012)

Old & Slow, file or grind out the magnet a bit to accommodate the spokes and be done with it.

XT 60's are light for that project. XT 90's non spark are better


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## PierreR (May 17, 2012)

Old & Slow, two more things I just thought of. Make sure you use dielectric grease on your connections and make sure you torque the crank arms to 25 ft lb or they will come loose and will damage the crank arm just enough that it will not stay tight. I have seen this problem with two other Bafang conversions where I did not do the work but inspired the project.


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## dundundata (May 15, 2009)

i soldered my own XT90 connectors, XT60 would be good too. Bafang is definitely a DIY project!


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