Something worth checking on your BBS01 or BBS02 during maintenance...

Fordulike

Esteemed Pedelecer
Feb 26, 2010
3,802
1,537
During an axle/final drive gear strip down to find the cause of another problem, I came across two issues that might be worth checking, if you ever do some big maintenance on your BBS01 or BBS02. I am not sure if this applies to the BBSHD, as I think it is different internally. Maybe someone could advise if this applies to that model or not.

For a while now, I've had an intermittent problem with the PAS, where every now and again it would cut power whilst pedaling. It was so infrequent, that it wasn't too much bother, although sometimes slightly irritating. On stripping down, I noticed that the PAS disc had a split on its outer edge. I assume that this is what was causing the intermittent functioning of the pedal assist.

PAS disc.jpg

To remove the PAS disc, there is a circlip. After taking the circlip off, the disc simply lifts off. Underneath, there are 5 screws holding the thing together.

I found all 5 screws to be very loose (sorry i didn't get a picture), so I removed them all, cleaned the area and screws up and screwed them back tight after applying threadlocker.
I had the same issue with a previous axle assembly, but had forgotten to check when I fitted my new one.

It's also well documented on various forums, that they don't tighten these screws very well at the factory. I'm also assuming that the raised heads of the screws may have caused my PAS disc to crack. I can't be sure, but anyone with a BBS01 or BBS02, please check at some stage, even if you are not having any issues.