Over volting BBS02

[SPYDER]

Hi everyone. I've searched on the net for a definitive answer to the question of whether it is possible to run a 36V BBS02 at 48V. Most people say no but a few say yes, but I've not found someone who has actually done it. Re-programming the Low voltage cutoff should pose no problem AFAIK.
What makes me think it is possible is the difference in chainwheel speed (cadence) between the two versions. The 36V is often quoted around 80rpm whereas the 48v varieties are given as around 110rpm. Are they using the same winding?

 

[Deleted member 4366]

There's not really much point in over-volting a crank drive unless you don't pedal. In the normal pedal range, it'll be less efficient than it was a 36v and with more power so it will most likely overheat. Crank-drives can't shed heat very easily like a hub-motor can.

Also, when you over-volt a hub-motor, you can enjoy the extra speed, but having a crank spin faster than you can pedal is not going to be much fun.

 

[Fordulike]

I think you'll end up getting an over voltage error on the display. What are you after, more torque, more speed or both?

 

[Nealh]

The software I don't think will allow the lvc to be reset that high and any how error 07 will show preventing operation.
I tried 12s lipo and no go.

 

[Paul chef]

I was wondering about this earlier, as the bfang 500w comes in 36v or 48v
Being a large guy who needs assistance to go uphill which one would be of more benefit?
But the batteries with the 36v seem to be higher in ah than the 48v ones so I was thinking if I went for 36v motor would a 48v with a high ah battery work with it

 

[anotherkiwi]

You will need a motor with an external controller. I will over volt the GSM to 12S to up the cadence a little, at the moment I spin too fast for it. Even then I will need to use a 48V controller to have a reasonable LVC of 3.45 V per cell which is kind of low for LiPo but not in the danger zone (3.2 V)

 

[Fordulike]

I was wondering about this earlier, as the bfang 500w comes in 36v or 48v
Being a large guy who needs assistance to go uphill which one would be of more benefit?
But the batteries with the 36v seem to be higher in ah than the 48v ones so I was thinking if I went for 36v motor would a 48v with a high ah battery work with it

You can reprogram the BBSxx series of controllers. Unless already tweaked for performance, they usually come factory set for eco usage. A programming cable can unlock extra torque and speed.

 

[Nealh]

I was wondering about this earlier, as the bfang 500w comes in 36v or 48v
Being a large guy who needs assistance to go uphill which one would be of more benefit?
But the batteries with the 36v seem to be higher in ah than the 48v ones so I was thinking if I went for 36v motor would a 48v with a high ah battery work with it

They indeed do but both have different controllers and software, BBS02 controller doesn't fit BBS01 as I said you will get 07 error and won't work, try it yourself hook up 12s lipo and you go nowhere.

 

[SPYDER]

Thanks everyone for your replies. The reason for my enquiry is that I have a chance at a 36V BBS02 but already have a 48V battery. I think I'll pass on it and resurrect the Q128c plan. Thanks again.

 

[Paul chef]

You can reprogram the BBSxx series of controllers. Unless already tweaked for performance, they usually come factory set for eco usage. A programming cable can unlock extra torque and speed.

Sorry to hijack the thread
Now seen a bbs 02 750w with 17ah battery comes with 46T chainwheel with an option of changing it to 44, 48, 52 chainwheel ?
I understand the 44 will be better for uphill and 52 for speed should I stick with 46 ?

 

[Fordulike]

Sorry to hijack the thread
Now seen a bbs 02 750w with 17ah battery comes with 46T chainwheel with an option of changing it to 44, 48, 52 chainwheel ?
I understand the 44 will be better for uphill and 52 for speed should I stick with 46 ?

If it were me, I'd go with the 44T. BBSxx's are happiest when the motor is spinning fast, so the 44T will put the least stress on the internals. The 44T will still get you to 30mph with an 11T cog on the cassette and 26" wheel.

If you find that the stock Bafang chainring gives you chainline issues, then you may have to go for something like a 42T Bling Ring. Link below:

https://www.brightonebikes.co.uk/store/c11/Lekkie®_Bling_Rings.html

 

[anotherkiwi]

44 for a 28" wheel, 46-48 for a 26" wheel and 52 for 24-20" wheel.

 

[Nealh]

You don't say what terrain usage but what ever a gearing that
allow you to spin easiest will be best.

 

[Paul chef]

You don't say what terrain usage but what ever a gearing that
allow you to spin easiest will be best.

Main use will be cycle paths some road with the occasional long steep hill