Bafang BBSO2 grinding noise

[Eric Hirst]

I have a Bafang BBSO2 conversion which suddenly started making a bad grinding noise. Maybe a couple hundred
miles on the motor, mainly dirt roads. I'm looking for guidance on where I should look to try to fix it. The noise happens any time the engine is running under any load, and doesn't happen when I coast or when I pedal with the engine off.

I've uploaded 21 second video to New video by Eric Hirst. Thanks in advance for any recommendations. So far I haven't even started taking the motor off the bike.

I'm also waiting to hear back from the vendor on this, but they usually take a couple days to respond.

-Eric

 

[Chalo]

My first guess is a bungled gear. They're no fun to get to, but they are available and replaceable.

There are online walkthroughs and tutorials to check out. Here's one:

Replacing A Peanut Buttered Nylon Primary Reduction Gear On The BBS02

It took several years for BMC to realize that Nylon planetary gears in their larger geared hubs like the Mac motors could not take the kind of loads that people were dumping into them. Eventually t…

electricbike-blog.com

 

[amberwolf]

I moved your thread from Forum Rules and Features (wierd place to post a problem thread) into Ebike Troubleshooting (the correct place to put it).

 

[Eric Hirst]

I moved your thread from Forum Rules and Features (wierd place to post a problem thread) into Ebike Troubleshooting (the correct place to put it).

Oops thank you for fixing that. My noob mistake.