Bafang crank engagement broken

Mark Lester

Pedelecer
Jun 16, 2017
42
4
61
uk
That's a seal just like I showed you in the photo above. They're easy to get out, like we told you, but you don't seem to listen. drill or punch a hole in it and hook it out. Simples!

You can get a replacement from your local bearing supplier for about £1.
The photo in that article is indeed of a rubber seal like the picture you have posted of a seal about 1cm deep which I have seen removed on video. The build date on that is january of last year, mine is november and they have a track record of just changing things in secret.
This is a steel washer, originally coated with about 2mm of rubber, secured by a sleeve. It does not, and indeed on none of the photos I have posted ever has had, any grease or sand or gunk or anything else, just bits of rubber that I have dutifully removed so we can see clearly.
If all it was was a rubber bung it would have disintegrated days ago.
I have just taken it to another engineer suggesting we drill holes in this and yank it out. He wasnt amused.
Given that we dont actually have consensus yet on what this is, one of you "sees what you mean now", and that the new part isn't going to be here till next week, and I am total idiot armed with a few spanners, a set of hex keys and a diy drill, we should perhaps just hang on a second.
 

jarob10

Esteemed Pedelecer
Jan 22, 2017
270
83
51
Uk
[QUOTE=" we should perhaps just hang on a second.[/QUOTE]

You're halfway there to its removal

Armed with a small flat blade screwdriver & hammer, rotate the washer in the housing - you'll soon get the sucker out. Controlled aggression required.

Order a couple of replacement dust seals from gbk if you haven't already - they don't come with the clutch
 
D

Deleted member 4366

Guest
If you don't want to take advice, all I can do is wish you good luck and suggest you find engineers that know what a seal is.
 
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Woosh

Trade Member
May 19, 2012
19,568
16,492
Southend on Sea
wooshbikes.co.uk
thank you Fordulike.
 

Mark Lester

Pedelecer
Jun 16, 2017
42
4
61
uk
ok, we're in. it's a washer, you have to get a rubber mallet and a flat head screwdriver and bang away at the outer edge of the washer till it buckles.
The voyage down the axle shaft continues, thanks to absolutely everyone for your moral support during these difficult times.
 
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rich_r

Pedelecer
Jun 23, 2017
89
32
50
North Yorkshire
Excellent. And also reassuring to know that you would also have been able to remove it using the method I suggested of drilling a hole in it and using a screw to pull it would probably have worked too.

Now let's see what was hiding underneath and causing your initial problem!
 

Mark Lester

Pedelecer
Jun 16, 2017
42
4
61
uk
the locking nut is now visible, but it wasnt interested in a pair of long pliers, i have the special spanner tool and a new clutch ring on their way from shenzen but its going to be a few days still.
 

Mark Lester

Pedelecer
Jun 16, 2017
42
4
61
uk
i got the retaining ring off, and removed the plastic cover, and 4 of the 5 screws on the clutch housing proper, and i now have one last bolt that looks like its been drilled against the thread. well it aint moving. this is the last obstacle i think, *sob*. i will clean all the grease off, will penetrating fluid help ?
 

Mark Lester

Pedelecer
Jun 16, 2017
42
4
61
uk
I dropped it off at my friendly car repair guys, he said he'd get it out so here's hoping. Also, I forgot to report that there were no seals between the two locking nuts. Once I got the damned seal thing off the front it was just a very tight locking nut (may be the circlip tool i have now would have done that) and then a second one that came straight off, no intermediate diaphragm things. Just sayin'.
 
D

Deleted member 4366

Guest
The new external seal is an update to the crappy rubber washer that went between the threaded retainers previously. You can get the seal from Greenbikekit.com, or take your assembled motor to your local bearing stockist. They should be able to find one the right size, but make sure that the lip is designed to keep water out, not oil in.
 
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Mark Lester

Pedelecer
Jun 16, 2017
42
4
61
uk
car shop got the 5th bolt out of this large gear wheel. i was expecting the cover/housing of the clutch to just come off now. i cant find any vids of this bit, i will examine and try to lever it out.
 

Mark Lester

Pedelecer
Jun 16, 2017
42
4
61
uk
ok we're in, my rubber mallet did the job. my only problem now is i took the clutch ring out, and now cant remember which direction the bugger goes!
 

Mark Lester

Pedelecer
Jun 16, 2017
42
4
61
uk
i guess the feet want to be pointing against my direction of pedal, which is anti clockwise as we look at it, so the pawls want to be pointing clockwise. btw, as diagnosed, the problem is a sticky pawl. one of them isnt as easy going as the other two. i'm sure its a tiny bit of sand.
 
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Fordulike

Esteemed Pedelecer
Feb 26, 2010
3,802
1,537
i think it wlil go either way, but i am not putting this back together just yet. will bike grease do or do i need to get some special stuff ?.
I wouldn't put any grease on the clutch ring, as it may prevent the pawls from doing their job. Clean it in some solvent, petrol, contact spray etc.., allow to fully dry, then squirt some silicone spray on the pawls.

On the final drive (large and small gear), I used to use this grease.

https://lucasoil.com/products/grease/lucas-x-tra-heavy-duty-grease

Should be fine for your Bafang, as I don't think you cane it off road.
 

Mark Lester

Pedelecer
Jun 16, 2017
42
4
61
uk
i got a new ring. i will clean this one up, its full of this thick grease btw, which yes, doesnt help much.
i am trying to build a touring saloon, off road is anything you could physically get a wheelchair along, e.g. tow paths, decent bridle paths.I put 35mm tyres on but along with the shed load of stuff on the back we're talking about managing 10mph for hours on end on the canal network.