DIY Fix for BBS02/BBSHD Pedal/Throttle Issue

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fechter   100 GW

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Re: DIY Fix for BBS02/BBSHD Pedal/Throttle Issue

Post by fechter » Jun 19 2018 8:05am

thetrevdev wrote:
Jun 18 2018 9:32pm
I just installed my first BBSHD yesterday. While a blast I am finding it difficult to control speed.
Can you describe how it is supposed to work?
I haven't installed my disc brake sensors yet so I am avoiding PAS > 0.
I am pedaling in PAS 0 and trying to manually control the assist but it is jerky and feels like 100% throttle.
I assumed this is just the way it is. Is this related to the issue you are discussing here? I have nothing to compare this to and don't know how it is supposed to work.
That sounds like mine was. It's possible there are some settings in the programming that might help, but I tried a lot of things with no success. To disable the PAS, I found all you need to do is unplug the PAS sensor inside the controller housing. This makes it pretty easy to put back later. I ran like that for about a year until I installed the fix.

You could try the higher PAS settings without using the throttle and see how it works. Just remember to pedal backwards to instantly stop the motor.
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Re: DIY Fix for BBS02/BBSHD Pedal/Throttle Issue

Post by thetrevdev » Jun 19 2018 8:28pm

That was really helpful. I didn't know you can pedal backwards to stop the motor in pedal assist.
After trying pedal assist on my commute it confirmed I really just want to use throttle to control my level of assist. I don't to worry about managing my gears when coming to a stop or worrying about power being applied when pedaling slow around obstacles etc. I will consider unplugging my PAS sensor.

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Re: DIY Fix for BBS02/BBSHD Pedal/Throttle Issue

Post by fechter » Jun 20 2018 2:05pm

Unplugging the PAS sensor is pretty easy. I recommend unplugging the battery first before working on anything. The hardest part is just removing the crank arm and chain ring to get access to the controller screws. My bike has a 30T chain ring, so much easier.
Remove the 3 screws holding the controller on and carefully pull it away from the motor. Unplug the PAS sensor (black connector). The plug may be stuck in with potting, but it comes out pretty easy. Be careful to avoid pinching any wires when placing the cover back on.

Down the road, you can consider doing the fix described in this thread. Having both PAS and throttle working is nice. If I set the PAS level to 0, it behaves the same as unplugging the PAS sensor and I use that for technical off road stuff.
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Re: DIY Fix for BBS02/BBSHD Pedal/Throttle Issue

Post by thetrevdev » Jun 20 2018 2:32pm

Thank you! That is so helpful!

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Re: DIY Fix for BBS02/BBSHD Pedal/Throttle Issue

Post by thetrevdev » Jun 20 2018 11:14pm

Do I disconnect the entire 4 pin connector or the grey wire wire in the connector?

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Re: DIY Fix for BBS02/BBSHD Pedal/Throttle Issue

Post by fechter » Jun 20 2018 11:19pm

thetrevdev wrote:
Jun 20 2018 11:14pm
Do I disconnect the entire 4 pin connector or the grey wire wire in the connector?
You can just unplug the whole connector as far as I know. When I did it, I cut the grey wire, but it seems you get the same result by unplugging the whole thing, which is a lot easier to put back later.
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Re: DIY Fix for BBS02/BBSHD Pedal/Throttle Issue

Post by DaDo.Bzz » Jun 30 2018 6:30pm

Just installed new controller HD. ( just a note, Luna is sending controller removed from a complete kit - it has broken connector - that locking part which holds connector in place - I dont find this professional from Luna!)

Also has spotted strange behaviour of throttle. It just turns on on full throtle. Throttle overrided PAS with old controller.

This must be a change in firmware, any chance to program old firmware using programming cable?

Anyway I had an issue that motor suddenly went on low power and also not smooth, after while it turned off. But I was able to turn it on again, but with low power and not smooth again. I have found one melted anderson connector. Anybody had similar experience? Anybody want old controller HD? I think fault was just in that melted connector and it lost contact.
LMX 81, 16S6P 60A
BBS02 on Cannondale Rz 120
BBSHD on CTM Scroll, XTR Di2, 700Wh 52V
Slovakia, Bratislava

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fechter   100 GW

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Re: DIY Fix for BBS02/BBSHD Pedal/Throttle Issue

Post by fechter » Jul 01 2018 10:12am

DaDo.Bzz wrote:
Jun 30 2018 6:30pm
This must be a change in firmware, any chance to program old firmware using programming cable?

Anyway I had an issue that motor suddenly went on low power and also not smooth, after while it turned off. But I was able to turn it on again, but with low power and not smooth again. I have found one melted anderson connector. Anybody had similar experience? Anybody want old controller HD? I think fault was just in that melted connector and it lost contact.
No, only Bafang has the firmware and they aren't sharing. The firmware gets flashed using a different connector that's located on the board.

Haven't heard of any phase wire connections going bad before. Possibly it wasn't plugged in all the way or one of the contacts wasn't fully seated.
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Re: DIY Fix for BBS02/BBSHD Pedal/Throttle Issue

Post by DaDo.Bzz » Jul 02 2018 2:45am

Hello Fechter

Yes, could be there was loose contact so it melted.

Anyway I did a ride yesterday with new controller and it is really bad. It is lalmost like on/off when you pedalling (to be precise throttle is active on 1000 - 1550 W) - high consumption then and also high stress when pedalling with low assistance. Omg, how they could broke something what worked well?!

Other observation. Looks to me also low voltage protection works different. With old controller it start to ramp down overall power while you were closer to cut of voltage. Now nothing and my bms came to play and turnedoff everything including light while I was downhilling in 50kmh- scary!
Had to go with phone light as looks like bms went active just after plugging the charger.
LMX 81, 16S6P 60A
BBS02 on Cannondale Rz 120
BBSHD on CTM Scroll, XTR Di2, 700Wh 52V
Slovakia, Bratislava

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fechter   100 GW

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Re: DIY Fix for BBS02/BBSHD Pedal/Throttle Issue

Post by fechter » Jul 02 2018 8:18am

The low voltage cutoff is programmable with the Bafang software. Sounds like it is set too low and the BMS is cutting off first.

If you have the Bafang software and programming cable, you may be able to read the settings from the old controller and copy them to the new one. You may see some improvement by simply changing some of the settings, but I don't know exactly what needs to be changed.

Bafang really screwed up when they did that version of firmware. Yours sounds exactly like mine was before I did the fix. You could do the fix or unplug the PAS sensor and run throttle only.
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Re: DIY Fix for BBS02/BBSHD Pedal/Throttle Issue

Post by bhaaf » Jul 02 2018 12:59pm

I received a new BBSHD controller from Luna the other day. It had the throttle problem but a friend put the “fletcher” fix on it. Now it’s nice and smooth.

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Re: DIY Fix for BBS02/BBSHD Pedal/Throttle Issue

Post by DaDo.Bzz » Jul 03 2018 7:58pm

Hello Fechter.

Yes, I copied exactly same setting to new controller and was surprised when controller didnt cut off motor.

Your tweak is great, just not sure if I wanna again dismantle it from bike and get to wires. Bloody bafang, did they even test it before releasing this new firmware?!
LMX 81, 16S6P 60A
BBS02 on Cannondale Rz 120
BBSHD on CTM Scroll, XTR Di2, 700Wh 52V
Slovakia, Bratislava

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Re: DIY Fix for BBS02/BBSHD Pedal/Throttle Issue

Post by gburb » Aug 26 2018 11:20pm

I've resorted to unplugging the pas on the new controllers. The newest issue I'm running into is I've never bothered with the speed sensor. I don't run a display (bypassed) so ive always just clipped the speed sensor off. With these new controllers, if it experiences an error 21 (not sensing magnet at speed sensor) then it will shut the motor down. It has never done that with the 6 or so motors I've had before. It would be awesome if I could now somehow bypass the speed sensor (short a couple of wires or something). Anyone know how I might accomplish that?

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fechter   100 GW

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Re: DIY Fix for BBS02/BBSHD Pedal/Throttle Issue

Post by fechter » Aug 27 2018 12:25pm

gburb wrote:
Aug 26 2018 11:20pm
I've resorted to unplugging the pas on the new controllers. The newest issue I'm running into is I've never bothered with the speed sensor. I don't run a display (bypassed) so ive always just clipped the speed sensor off. With these new controllers, if it experiences an error 21 (not sensing magnet at speed sensor) then it will shut the motor down. It has never done that with the 6 or so motors I've had before. It would be awesome if I could now somehow bypass the speed sensor (short a couple of wires or something). Anyone know how I might accomplish that?
See this topic:
viewtopic.php?f=28&t=90821&p=1406842#p1406842
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Re: DIY Fix for BBS02/BBSHD Pedal/Throttle Issue

Post by banzai » Oct 17 2018 3:55pm

About the transistor to be used, I have a MPSA06 and a MPSA14, can any of them replace the others listed in previous post?

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fechter   100 GW

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Re: DIY Fix for BBS02/BBSHD Pedal/Throttle Issue

Post by fechter » Oct 17 2018 6:16pm

Mpsa14 should work fine. Just double check the pin out. Some may have the legs arranged differently.
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Re: DIY Fix for BBS02/BBSHD Pedal/Throttle Issue

Post by banzai » Oct 19 2018 3:56pm

Thanks. Just got a second new controller, 36v500w, marked october 2018, think that best way is remove pot from the area where cables are welded to board, the zone where cables enter the controller is a mess and I fear that if I remove the pot there it will be impossible to have it waterproof again unless I buy the Magic Rubber compound. Do you have info if Bafang reverted the firmware mode? Maybe will test once "as is"...

Another thing, are you aware if there are posts im this forum about modifying a 750w with a 500w controller? Searched but could not find. Here in italy a few ppl did it, to have less rpm and less heat when climbing step hills.

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fechter   100 GW

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Re: DIY Fix for BBS02/BBSHD Pedal/Throttle Issue

Post by fechter » Oct 20 2018 6:41pm

Definitely test it before digging into it. I haven't run across any 500W versions. Not sure, but you may be able to reprogram it to be the same as the 750W.
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Re: DIY Fix for BBS02/BBSHD Pedal/Throttle Issue

Post by espresso » Oct 21 2018 7:55am

I see that the Domino throttle has a micro switch built in. Couldn't this be used to switch off the PAS as soon as the throttle is activated?

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fechter   100 GW

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Re: DIY Fix for BBS02/BBSHD Pedal/Throttle Issue

Post by fechter » Oct 21 2018 12:21pm

espresso wrote:
Oct 21 2018 7:55am
I see that the Domino throttle has a micro switch built in. Couldn't this be used to switch off the PAS as soon as the throttle is activated?
Yes. It should work perfectly and not require cutting into anything.
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Re: DIY Fix for BBS02/BBSHD Pedal/Throttle Issue

Post by Alan B » Oct 25 2018 12:01am

espresso wrote:
Oct 21 2018 7:55am
I see that the Domino throttle has a micro switch built in. Couldn't this be used to switch off the PAS as soon as the throttle is activated?
Nice solution.

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Re: DIY Fix for BBS02/BBSHD Pedal/Throttle Issue

Post by sanjuro » Oct 27 2018 7:13am

espresso wrote:
Oct 21 2018 7:55am
I see that the Domino throttle has a micro switch built in. Couldn't this be used to switch off the PAS as soon as the throttle is activated?
can you link where i can buy that throttle from please

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Re: DIY Fix for BBS02/BBSHD Pedal/Throttle Issue

Post by JPLabs » Oct 27 2018 2:09pm

To use this throttle switch, we need to break out the PAS wire inside the motor, and switch that, right?

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Re: DIY Fix for BBS02/BBSHD Pedal/Throttle Issue

Post by fechter » Oct 27 2018 3:39pm

JPLabs wrote:
Oct 27 2018 2:09pm
To use this throttle switch, we need to break out the PAS wire inside the motor, and switch that, right?
You need to just tap into the black and grey wires on the PAS connector. The switch closes when you open the throttle so we want to ground the grey signal line.
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Re: DIY Fix for BBS02/BBSHD Pedal/Throttle Issue

Post by JPLabs » Oct 27 2018 6:25pm

Ok, thanks!

I just got my first new-style controller, and I'm not liking the throttle wheelies at all. I'll unplug for now.

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