Crankset SLIPPAGE 750 watt Bafang middrive

[rmwac]

Help!!! I'm out on a ride, and my Bafang 750 watt mid drive suddenly began to slip. The crankset and chainring are de-coupled, and I cannot even pedal manually. Spousal unit is on her way to collect me. Probably no fixing it out in the field. Can I get some info on where to begin troubleshooting the unit. The unit is only a few months old with 200 miles on it. Thanks, Rmwac

[Zippy]

Well you better examine it and see what came loose first off.

[Poco Askew]

...The crankset and chainring are de-coupled, and I cannot even pedal manually. ...

Do you mean you are able to pedal but the chainring doesn't turn? Or are you not able to pedal?

[tommie]

Clutch maybe??

[JPLabs]

IF the pedals spin without turning the chainring, that would be the clutch, yes, pretty sure. There's a one-way rotating element which allows the motor to spin without the pedals spinning. If that fails, allowing rotation in both directions, instead of in one direction only, you can't input power via the pedals anymore. Sounds like your situation.

[ykick]

I once had the chain hop off and it behaved this way. At 1st glance I didn't realize the chain had hopped off because it was merely sitting on the motor housing next to the chain ring. I'm old, it was kinda dark, my eyes aren't that great anymore. I walked the damn thing home a short distance and even contacted Luna support before I took a closer look and realized what was actually going on. I'd just assumed the worst from the get go and didn't give it a close enough inspection to realize the simplicity of the problem.

[JPLabs]

Thanks for the chuckle.

I could see that happening easily enough. But hearing of your goof makes a great point. Experienced guys still need to verify the basics.

'Is the PC plugged in?'

Arrrrrrrrrrrrgggggh! Chokes phone. But a necessary question, in fact.

I've spent several minutes panicking before noting my battery is un-plugged, myself. :)

[ykick]

Yes, sometimes our "experience" does get in the way since we know a thing or two because we've seen a thing or two. Easy to jump to conclusions before checking the basics.

[calfee20]

The same thing almost happened to me. The chain jumped between the sprocket and the plastic guard that the BBS02s come with. It made surprisingly little noise and I was sure the clutch had let go. I was getting ready to call someone and then decided to look again and flip the bike over. I noticed the chain before I got the bike upside down.

I totally agree on the eyes comment. I miss things now that I never used to because I need so much more light to compensate for age.