front sprocket chainring removal Bafang (correction WEBO 250 watt motor)

[bbrruno]

Can anyone tell me how to remove the front sprocket—the front chainring—on a Bafang BBS01? It’s a recent bike; I don’t know the motor code.? It's a 250 watt motor. It’s not secured with bolts or screws. It’s threaded in place, and there’s an internal locking ring with four notches. I bought a tool on AliExpress with four protrusions, but apparently that’s for the left side, and it’s way too small. So I need a larger tool like that. My first question is, is it true that I just need to turn that inner retaining ring to the right—clockwise—and it will automatically come loose? It’s very tight. Do I just keep turning until it comes loose, or is there something else I need to keep in mind? Do I need a special tool?

 

[mrmojorising]

Can you take a picture of it? All BBS mid drive motors use chainrings that are mounted on with five bolts, so it's not clear what you have on hand. It definitely shouldn't be on so tight that you feel like it will break something trying to loosen it

 

[bbrruno]

 

[mrmojorising]

Ah ok, thanks. This is not a bafang drive, it appears to be a BEWO 250W mid drive. I haven't personally used one of these drives before, but I believe you're right about it being reverse threaded.

Looks like there was a similar thread here about trying to locate an appropriate tool: Looking for this tool to remove my front chainring on a bewo middrive

 

[mrmojorising]

I found another thread Here which mentions it's a left hand thread (clockwise to loosen) too

 

[bbrruno]

Thank you for your correction and instructions!

 

[bbrruno]

A dealer just told methat the retaining ring is under very high tension, so you can't remove it with normal tools. You need a special tool that actually holds the retaining ring in place, which allows you to loosen the sprocket. If you were to simply use a lever of, say, one and a half meters, you would destroy the inside. So that is the information I received. Now, the thing is, there are no drawings to be found on the internet. Is there anyone who might have more info about this motor? (Weno WB-M01) Can you open it up further? Once the sprocket is removed, is it easy to go further to lubricate the inner gears? Does anyone know if I can just unscrew the cover, after removing the crank on the other side, and just pull it out to lubricate?

 

[mrmojorising]

It seems like someone did successfully remove the crank case cover for lubrication without needing to remove the chainring, so you could give that a go: Bewo, New Crank-drive Motor

Looks like they just removed those six bolts through the chainring and the whole assembly came off