BBS-02 Power Output Fluctuations?

John L.

Member
Okay, so after 6 months I'm generally loving my Bafang outfitted Surly Ogre. It has been reliable and stout, flattening hills and turning them into opportunities to ride rather than something to be dreaded. I can tow my fully loaded cargo trailer with no problem. Battery life has been very good. Really nothing major to complain about.

My question is this: is it normal for the power output of the BBS-02 to fluctuate slightly during hill-climbs? Sometimes (usually in PAS 1), I'll be pedaling steadily at a moderate cadence in a low gear on a slight incline. I'm not traveling near the speed limit of the motor. Neither my pedal cadence nor the hill changes, but I feel a temporary slight decrease in power output from the motor. It usually lasts a few seconds, and then I can feel the power output increase back to where it was before. The LED readout will show the wattage used by the motor decrease during these episodes. The motor doesn't completely cut off, but power output decreases. I've chalked it up to the controller easing up in order to avoid overheating the motor (I'm a heavy rider, BTW). I'm wondering if this is normal or an issue with the controller?
 

Woody

New Member
I've noticed the same thing, not only with my 8FUN but with another ebike as well. Sorry though, I don't know what causes it to do that.

I've also noticed that your thread has 38 views and not a single reply from anyone except myself, another new member.
 

RoyL

Active Member
Think this is a feature of the standard bafang controller programming, i notice it on all PAS levels. If you read on Endless sphere its discussed there.
 

flymeaway

Well-Known Member
is it normal for the power output of the BBS-02 to fluctuate

Hi John,

I have 3 bikes with BBS02 drives, with total miles ridden over 6,000. I only have one with the C965 LCD and when I'm riding the watt output is constantly changing. I don't notice any significant fluctuation even as the meter shows power fluctuations.

Court J.
 

John L.

Member
Thanks for the feedback, everybody. It would appear to be a normal part of the Bafang controller programming. Court, I agree with your observation about the watt output, and sometimes it is too minor to notice, but there are times when the fluctuation of power is noticeable in the pedals (to me, anyway). I also have the C965, and I noticed the "feel" of the power fluctuation long before I checked the wattage output on the display. It sometimes can be a hindrance to maintaining a nice, smooth cadence. As I mentioned, I am generally very happy with the product, but it is an issue that I'm curious about. As Roy suggests, I may do a bit more research on Endless Sphere.