Soldering the shunt on the BBS02 for more amps...

[LikeToRideMyBike]

There doesn't seem to be a thread explaining in detail how to increase the amperage of the BBSXX motors by adding solder to the shunt. I'm assuming either the black or the gray prong plugs is the shunt... Where exactly is the solder added?

And I've read that you use just a spot of solder... Does the amount of solder you add matter?

thanks all!

 

[alfantastic]

There doesn't seem to be a thread explaining in detail how to increase the amperage of the BBSXX motors by adding solder to the shunt. I'm assuming either the black or the gray prong plugs is the shunt... Where exactly is the solder added?

And I've read that you use just a spot of solder... Does the amount of solder you add matter?

thanks all!

I know it's your call, but I personally wouldn't be soldering the shunt on a BBSxx controller. They're not like your normal rectangle box style controllers. and are easily blown through misuse.

Have you tried releasing all the power via a programming cable? Changing the 'Keep Current' setting to 100%, provides a significant improvement from factory settings.

 

[spinningmagnets]

Here's a thread that might have some useful info on soldering shunts, do's and don'ts. Personally, I don't recommend it for the BBS02 if it is using a true 52V X 25A

https://endless-sphere.com/forums/viewtopic.php?f=2&t=44784#p652132

 

[Ykick]

Soldering shunts' never a good idea on hub motor controllers. Let alone a BBS02.

25A is the most peak current that should ever be drawn and even that for only a short period of time while not lugging the motor.

It's very hard to tell if/when you're lugging these BB motors.

15A is the most continuous current I'd pull for long periods of time.

 

[LikeToRideMyBike]

Here's a thread that might have some useful info on soldering shunts, do's and don'ts. Personally, I don't recommend it for the BBS02 if it is using a true 52V X 25A

https://endless-sphere.com/forums/viewtopic.php?f=2&t=44784#p652132

I looked through this thread, but I haven't seen anything that looks like these shunts inside of the BBS02. It must look different than the shunts that are in the external hub controllers.

I'm surprised no one has explained on here how to do this, since they use to come from Bafang with extra solder to make them 30 amps. Even before they added 3 extra mosfets, and the 3077's. https://endless-sphere.com/forums/viewtopic.php?f=28&t=79837&p=1180294#p1180294

It's got to be safer now more than ever to solder the shunt, and an aquarium temperature gauge installed in the controller would be a necessary precaution.

 

[spinningmagnets]

I believe the shunt in hidden under the potting, but the controllers that came from the factory that are capable of 30A peaks have a certain resistor changed to a different Ohms value. That is the proper way to raise the max amps of a controller. Again, do as you please, but...I cannot recommend the BBS02 be run at over 25A (for other readers who are following this, or find it in a search)

 

[Samd]

My thoughts are about the nylon gears copping the backlash.
If there was a way to increase the amps but reduce the shock due to WOT at low speed takeoff maybe it'd work...

 

[LikeToRideMyBike]

I believe the shunt in hidden under the potting, but the controllers that came from the factory that are capable of 30A peaks have a certain resistor changed to a different Ohms value. That is the proper way to raise the max amps of a controller. Again, do as you please, but...I cannot recommend the BBS02 be run at over 25A (for other readers who are following this, or find it in a search)

Hmmm, I saw on the first link you posted that people were soldering on things to change the ohms. Is this what you are referring to:

https://endless-sphere.com/forums/viewtopic.php?f=2&t=44784#p652140

 

[LyonNightroad]

My thoughts are about the nylon gears copping the backlash.
If there was a way to increase the amps but reduce the shock due to WOT at low speed takeoff maybe it'd work...

I believe there is a setting for this.

 

[spinningmagnets]

LikeToRideMyBike, I don't ever recommend soldering the shunt. I prefer to recommend that builders research and select components that work properly for the task they are give, with an adequate safety margin. That being said, I also enjoy experimenting, and occasionally breaking things to "see how much they can take".

Yes, that is the thread that I was referring to. I haven't soldered a shunt before, but I have read about others who have. If you live where its fairly flat, motors and controllers can often take a temporary peak of amps that are significantly above what they are generally rated at.

The danger is in a system that draws max amps on a long uphill climb, while the controller and motor are not given a "cooling off" phase to help it survive.

 

[LikeToRideMyBike]

LikeToRideMyBike, I don't ever recommend soldering the shunt. I prefer to recommend that builders research and select components that work properly for the task they are give, with an adequate safety margin. That being said, I also enjoy experimenting, and occasionally breaking things to "see how much they can take".

Yes, that is the thread that I was referring to. I haven't soldered a shunt before, but I have read about others who have. If you live where its fairly flat, motors and controllers can often take a temporary peak of amps that are significantly above what they are generally rated at.

The danger is in a system that draws max amps on a long uphill climb, while the controller and motor are not given a "cooling off" phase to help it survive.

thanks spinningmagnets, yeah it's probably not a good idea. ha! And I guess no one who has seen this thread has solders the shunt of their BBS02. They are becoming sort of yesterday's motor so I figured people would be pushing them to their limits after buying a brand new BBSHD. In the thread you posted, I read that someone wrapped copper around the shunt so that it's less permanent, but still gives a boost in amps. Still not a BBS02 though. It's easy to locate the shunt in hub motor controllers. I don't know, maybe someone will chime in later whose had experience with this specific thing just for the sake of experimentation and learning. Just for the sake of, like you say occasionally breaking things to see how much they can take.

 

[Gregory]

.... but I haven't seen anything that looks like these shunts inside of the BBS02. It must look different than the shunts that are in the external hub controllers.

Do you have a picture of the inside of the BBS02? It may not use a solid current shunt resistor at all.
It could use the voltage drop across a MOSFET or a hall effect current sensor (unlikely) to measure current.

 

[LikeToRideMyBike]

.... but I haven't seen anything that looks like these shunts inside of the BBS02. It must look different than the shunts that are in the external hub controllers.

Do you have a picture of the inside of the BBS02? It may not use a solid current shunt resistor at all.
It could use the voltage drop across a MOSFET or a hall effect current sensor (unlikely) to measure current.

 

[Gregory]

Can't see anything there for all the potting.

If there is a current shunt resistor it will be in series with the (low side?) MOSFET source pins and ground
i.e directly in between the black battery wire and the right hand side pins (source) of some of the the MOSFETs.

Otherwise I'd expect they use MOSFET trickery to measure current, and programming changes are required.

 

[gman1971]

Why bother with modifying a perfectly good BBS02? No amount of modding on that BBS02 will ever be a match any powerful hub motor running anything above 2 kW, heck, even the Cyclone 3000W will eat that modified BBS02 for breakfast any day of the week, and do so reliably; even when running @ 36V too... My advice would be to get something else worthy of being hot-rodded then shunt-mod the piss out of it to see how fast you can get it to go, but shunt modding the BBS02 is sort of pointless as its already pretty much maxed out from factory; plus the performance you'll gain will be marginal compared to getting something else.

But hey, its your money... spend it at your own peril.

G.

 

[Sebz]

Why bother with modifying a perfectly good BBS02? No amount of modding on that BBS02 will ever be a match any powerful hub motor running anything above 2 kW, heck, even the Cyclone 3000W will eat that modified BBS02 for breakfast any day of the week, and do so reliably; even when running @ 36V too... My advice would be to get something else worthy of being hot-rodded then shunt-mod the piss out of it to see how fast you can get it to go, but shunt modding the BBS02 is sort of pointless as its already pretty much maxed out from factory; plus the performance you'll gain will be marginal compared to getting something else.

But hey, its your money... spend it at your own peril.

G.

I was reading that post and thinking this is the kind of post I would see Gman write on the electric bike forum..... Then I looked at who wrote it

 

[gman1971]

Why bother with modifying a perfectly good BBS02? No amount of modding on that BBS02 will ever be a match any powerful hub motor running anything above 2 kW, heck, even the Cyclone 3000W will eat that modified BBS02 for breakfast any day of the week, and do so reliably; even when running @ 36V too... My advice would be to get something else worthy of being hot-rodded then shunt-mod the piss out of it to see how fast you can get it to go, but shunt modding the BBS02 is sort of pointless as its already pretty much maxed out from factory; plus the performance you'll gain will be marginal compared to getting something else.

But hey, its your money... spend it at your own peril.

G.

I was reading that post and thinking this is the kind of post I would see Gman write on the electric bike forum..... Then I looked at who wrote it

Yes, I am the same across all forums; but in all seriousness Sebz, why on Earth would you want to ruin a perfectly nice BBS02 to get more power when there are some other options out there that will deliver a lot more power for a lot less investment? I am not even talking C3000W alone, there are DD hub motors that can deliver a lot of power for very cheap...

G.

 

[Sebz]

Why bother with modifying a perfectly good BBS02? No amount of modding on that BBS02 will ever be a match any powerful hub motor running anything above 2 kW, heck, even the Cyclone 3000W will eat that modified BBS02 for breakfast any day of the week, and do so reliably; even when running @ 36V too... My advice would be to get something else worthy of being hot-rodded then shunt-mod the piss out of it to see how fast you can get it to go, but shunt modding the BBS02 is sort of pointless as its already pretty much maxed out from factory; plus the performance you'll gain will be marginal compared to getting something else.

But hey, its your money... spend it at your own peril.

G.

I was reading that post and thinking this is the kind of post I would see Gman write on the electric bike forum..... Then I looked at who wrote it

Yes, I am the same across all forums; but in all seriousness Sebz, why on Earth would you want to ruin a perfectly nice BBS02 to get more power when there are some other options out there that will deliver a lot more power for a lot less investment? I am not even talking C3000W alone, there are DD hub motors that can deliver a lot of power for very cheap...

G.

I would not modify a BBS02.... I think too many people destroyed the 02 with 25amps alone.... the only worthy of modifying is the HD...Eric proved that it could be ridden at 3000W. But if you really want 3000W or more you know what mid drive to start with!

 

[gman1971]

I didn't say it... lol, but yeah, the Cyclone 3000W is a great solution for your eBike need-more-power "problems"...

G.

 

[LikeToRideMyBike]

Thanks guys.

 

[LikeToRideMyBike]

https://endless-sphere.com/forums/viewtopic.php?f=28&t=79837&p=1180294#p1180294

 

[gman1971]

Then go ahead and do it; but hope it holds, b/c some people here will be laughing real hard once it strips...