Help with Bafang Bird bike motor

[Baz the balloon man]

Hi All

Thought to post this before I go at it as its quite common damage on e bikes .

Bought in the Bird bike to sell as spares the motor wire was damaged from a fall finally got round to doing a repair .

Sadly not possible to do a join at the end of the Axel because the small green wire is broken in side the axel.

Never done this before .

I may be able to loosen the PCB and get enough of the green wire to solder to heat shrink ECT not sure if it will gently pull through.

Prefer to try and fit a new cable and plug I think just to gently prise off the plastic collar ? To free the cable

Can any one advise on this before I damage it .

U tube video would help .

I think we should have master class videos from the professionals on here if you guys are up for it . It would be a credit to this site in my opinion.
And very helpful to owners , DIY and traders like me who are starting out.

I want to sell the motor and rim when done .

Very clean and dry compared to Suntours motors which have done around 1000 odd miles .

Any other advise ie where and which type of grease to use when assembling it would be welcome for a professional standard repair .

Cheers
Baz

 

[Sparksandbangs]

That looks a pain to do. It might be one of those where you have to disassemble knowing that it will never go back together again. Then you will have a better idea how to do it next time.

 

[saneagle]

The way I repair them is to buy a motor cable from eBay for £10 or less from AliExpress if you can wait a week. Unsolder the 9 wires on the inside of the motor after marking which is which. Thread through the new cable and solder it.

The tricky bit is to get the cable past the right angle bend in the middle of the motor. You have to arrange the wires at the end of the cable in a tapered shape with one or two of the phase wires longer than the rest. You also need a pair of thin pliers that can reach in and grab those wires, then you can wiggle the whole cable through. I never used grease, but I think a liberal coating of grease on the end of the cable would help a lot.

 

[Sparksandbangs]

I never used grease, but I think a liberal coating of grease on the end of the cable would help a lot.

How about a bit washing up liquid? It is wonder juice for squeezing stuff through tight spaces. Not as messy as grease.

 

[Baz the balloon man]

The way I repair them is to buy a motor cable from eBay for £10 or less from AliExpress if you can wait a week. Unsolder the 9 wires on the inside of the motor after marking which is which. Thread through the new cable and solder it.

The tricky bit is to get the cable past the right angle bend in the middle of the motor. You have to arrange the wires at the end of the cable in a tapered shape with one or two of the phase wires longer than the rest. You also need a pair of thin pliers that can reach in and grab those wires, then you can wiggle the whole cable through. I never used grease, but I think a liberal coating of grease on the end of the cable would help a lot.

Thanks I have a cable ready new one , I will give it a go

 

[Baz the balloon man]

So just confirming unscrew the PCB , unsolder the wires . Pull the old one out .

Then feed a new cable in without taking off the collar round the axel that looks like it’s holding the cable in place ?

 

[Baz the balloon man]

Take a photo of wire positions.

 

[thelarkbox]

Feed a wire then string then para-cord thru first and use pvc tape to attach the cord to the replacement flex using the tape to create a tapered shape with the flex ends.

(para cord can have its inner core threads removed leaving the sleeve only which is strong and flattened thin can be wrapped around the outer flex for extra grip if needed while stil fitting thru the hole)

Once the flex has started to penetrate fully consider adding some silicone sealant to the flex as it enters for seaing.

 

[Baz the balloon man]

Feed a wire then string then para-cord thru first and use pvc tape to attach the cord to the replacement flex using the tape to create a tapered shape with the flex ends.

(para cord can have its inner core threads removed leaving the sleeve only which is strong and flattened thin can be wrapped around the outer flex for extra grip if needed while stil fitting thru the hole)

Once the flex has started to penetrate fully consider adding some silicone sealant to the flex as it enters for seaing.

Thanks very helpful ,

 

[AntonyC]

> master class videos from the professionals

Here you go, and a dab of grease would surely help.

 

[Baz the balloon man]

With the grease I ment the grease around the inner hub casing it seems to be more of a silica rather than say cooper ease or general purpose grease .

When I opened the scrap Suntours motor I thought a silicone seal around the inner outer edge might help stop water getting in if say just fitting a new insert motor .

 

[Nealh]

My go to lube for ease of pulling stuff thru tight spaces is to raid the fridge for a bit of spread , slippery as running on ball bearings (not that I have tried running on them). But you know what I'm getting at.

 

[saneagle]

So just confirming unscrew the PCB , unsolder the wires . Pull the old one out .

Then feed a new cable in without taking off the collar round the axel that looks like it’s holding the cable in place ?

The phase wires are normally soldered to the coils, not the pcb.

 

[Baz the balloon man]

My go to lube for ease of pulling stuff thru tight spaces is to raid the fridge for a bit spread , slippery as running on ball bearings (not that I have tried running on them). But you know what I'm getting at.

LOL guys thanks for all the grease lightning advise I was looking at the Circup and the collar on the axel where the wire comes out and goes to the PCB.

So I take it pull and squeeze the wire through and make sure to seal up the motor to stop water ingress .

I think I have some slush machine lube or Vaseline just in case I need to pull it through with my teeth ie food safe I had a Slush Puppie Franchise 35 years ago and instead of selling the powers that be decided we needed to learn how to fix Slush machines instead of concentrating on Sales just before they sacked them all and used Couriers because every one who got a free machine rental then got stitched up for sugar base with a few chemicals in it ,. Or init!

The American’s are good at this type of closed shop ie agents and distributors.
I just sold my Slush machine’s One from China and one Electrofreez one .
The latter being a money maker when it’s hot .

How about a Pedelechs Meet say at the Ace Cafe I know we are not bikers but good famous venue to boot ?



Thoughts please

 

[Baz the balloon man]

The phase wires are normally soldered to the coils, not the pcb.

I see have not got that far yet !

 

[Baz the balloon man]

LOL guys thanks for all the grease lightning advise I was looking at the Circup and the collar on the axel where the wire comes out and goes to the PCB.

PINCHING THE CABLE

 

[thelarkbox]

LOL guys thanks for all the grease lightning advise I was looking at the Circup and the collar on the axel where the wire comes out and goes to the PCB.

PINCHING THE CABLE

clear the old flex out to see what your dealing with more clearly, it could be a 'shallow' enough pinch to allow a shim to protect the inch or so of sleeve if anny you need to pull through?

and with no flex to damage you could apply some more oomph to any levering up

looks like it was banged on as a friction fit but i could be mis seeing the pic. so levering or pulling from 2x or more equally spaced angles may be needed?

ps im a bodger with grazed knuckles.. no expert.

 

[Baz the balloon man]

A new classification of pedlech is needed just like in 914 when bicycles where made into mop heads

Going forward there must be a new legislation to deal with new technology with a mind to safe riding and e bikes that are safe to ride say engineered to be safe up to say 30mph with long range battery’s that are safe and can be re hat a place of work

Money maker but down side say in Asia. I have been many bike traffic jams in a clunif say ou go on the walk way you are going to pay a months wages as a fine into the pock7of the police man

 

[Baz the balloon man]

clear the old flex out to see what your dealing with more clearly, it could be a 'shallow' enough pinch to allow a shim to protect the inch or so of sleeve if anny you need to pull through?

and with no flex to damage you could apply some more oomph to any levering up

looks like it was banged on as a friction fit but i could be mis seeing the pic. so levering or pulling from 2x or more equally spaced angles may be needed?

ps im a bodger with grazed knuckles.. no expert.

Nor am I

 

[Baz the balloon man]

A new classification of pedlech is needed just like in 914 when bicycles where made into mop heads

Going forward there must be a new legislation to deal with new technology with a mind to safe riding and e bikes that are safe to ride say engineered to be safe up to say 30mph with long range battery’s that are safe and can be re hat a place of work

Money maker but down side say in Asia. I have been many bike traffic jams in a clunif say ou go on the walk way you are going to pay a months wages as a fine into the pock7of the police man

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