Bafang BBS02 Alert

Discussions related to motors other than hub motors.
This includes R/C motors, botttom bracket, roller and geared drives.
Post Reply
User avatar
Rassy   10 MW

10 MW
Posts: 2019
Joined: Apr 08 2007 10:58am
Location: Eugene, Oregon USA

Bafang BBS02 Alert

Post by Rassy » Oct 12 2017 8:58pm

I know we all have different riding styles and preferences, but I fell into a funny trap this year with the purchase of my sixth BBS02. Namely, I have been unable to find any solution or settings that allow pedaling along with normal throttle usage. At full throttle you can also pedal, but at anything less than full throttle while pedaling there is no throttle response. Stated another way, if you are pedaling in any PAS level, 0 through 9, and attempt to use the throttle there is no throttle response until you get to full throttle. If you aren't pedaling or quit pedaling then there is normal throttle response.

Since I had purchased two of the new versions ,BBS02B, this year, and the one that did not have a dedicated gear sensor worked the same as my previous BBS02s, whereas the one with a dedicated gear sensor had the abnormal pedal/throttle issue, I figured the problem was associated with the dedicated gear sensor.

But now, after several weeks of research including several email exchanges with the vendor, the purchase and use of a controller programming cable, and the purchase and installation of a new controller I am back to square one on why these new BBS02 controllers behave this way, but this does not appear to be limited to the controllers that have the dedicated gear sensor:

Controller on first BBS02B with date/serial 1609270057 and no gear sensor has no pedal/throttle issue;

Controller on second BBS02B with date/serial 1705310074 and a dedicated gear sensor has the pedal/throttle issue; and

Replacement controller installed on second BBS02B with date/serial 1709140337 and no gear sensor has the pedal/throttle issue.

Anyway, even though I usually just pedal with no assist or a fairly low assist I'm not affected too adversely, but I miss being able to get a boost from the throttle unless I also quit pedaling.

My reason for this post is to inform current or perspective purchasers of the new BBS02B to be aware of this potential issue. If anyone can provide more information please do so. I expect the answer may lay in a controller setting we aren't yet aware of since all three of these controllers are firmware version 2.0.1.1.
Last edited by Rassy on Oct 14 2017 5:13pm, edited 1 time in total.
-Rassy-
One Tadpole Trike equipped with a Bafang BBS02
https://endless-sphere.com/forums/viewt ... 28&t=69419
One Delta Trike equipped with a Bafang BBS02
https://endless-sphere.com/forums/viewt ... 0#p1291260

mcollister   1 µW

1 µW
Posts: 1
Joined: Oct 13 2017 9:10pm

Re: Bafang BBS02 Alert

Post by mcollister » Oct 13 2017 9:28pm

Mine behaves this way as well Here is how I understand it:
lets say you are in PAS three (my favorite commute setting) whatever is programmed for the power assist level cannot be exceeded, so either you are supplying some of the energy while pedaling, or the motor supplies the total energy if you are not.
whether you or the motor is supplying the power depends on how fast you are pedaling. Try pedaling more slowly, and you will feel the motor take up the slack. The throttle still works, but is limited by the PAS setting. I don't think it is a malfunction, just how it works. I have no clue how the older ones worked. What are your current PAS settings and how did you arrive at those particular vaiues (some very good 'recipes' out there. I use Karl's special sauce from hackers guide to programming bbs02

Someone PLEASE correct me if the above is total BS, as I have no hard data, just inferences from how mine behaves

User avatar
Rassy   10 MW

10 MW
Posts: 2019
Joined: Apr 08 2007 10:58am
Location: Eugene, Oregon USA

Re: Bafang BBS02 Alert

Post by Rassy » Oct 14 2017 6:07pm

mcollister wrote:
Try pedaling more slowly, and you will feel the motor take up the slack. The throttle still works, but is limited by the PAS setting
If I read your statement correctly you are saying that you can keep pedaling while you are able to use the throttle to run faster. Can you adjust the amount of throttle to match your cadence as you apply some pedal to help you get up a hill that the PAS setting doesn't allow quite enough power for, or do you only get the throttle help when you go to full throttle? Also, what is the date on your controller (first six numbers on the third line)?

Also, you mentioned using Karl's special sauce, which has the Designated Assist Level under Throttle Handle settings set to "9". If your throttle is limited by the PAS setting do you have this setting set to "By Display Command"? If so, what happens when you apply limited throttle as you pedal along in PAS0?

mcollister wrote:
What are your current PAS settings and how did you arrive at those particular values (some very good 'recipes' out there. I use Karl's special sauce from hackers guide to programming bbs02
The purpose of this thread isn't to get into all the fine tuning that can be done, but rather to address the issue of some, if not all, of the 2017 controllers not allowing you to pedal at the same time that you apply a variable throttle, in all 10 PAS levels, 0 through 9. Full throttle works, but it comes on strong with a hard "jerk" on the drive train and doesn't allow you to adjust the throttle to match your desired cadence.

EDIT: I have recently "fixed" a 2017 BBS02 controller that had the pedal/throttle issue:

http://www.endless-sphere.com/forums/vi ... 8c8cc0068a
-Rassy-
One Tadpole Trike equipped with a Bafang BBS02
https://endless-sphere.com/forums/viewt ... 28&t=69419
One Delta Trike equipped with a Bafang BBS02
https://endless-sphere.com/forums/viewt ... 0#p1291260

Post Reply