48V BBS02 at 36V?

[tomjasz]

You can push it harder on lower voltage , but it can't run any faster than what physics allows. Rough rule of thumb is 20% slower on 36V as opposed to 48V.

Well interesting. I have a few CA3's and shunts to do temporary testing. My 48V battery pulls 500w to run 14MPH, my 36V bikes pull 500W to do 13MPH.

 

[harryS]

Well interesting. I have a few CA3's and shunts to do temporary testing. My 48V battery pulls 500w to run 14MPH, my 36V bikes pull 500W to do 13MPH.

I rediscovered that once, doing battery mileage tests. It's the same amount of work for the the two batteries. This was back when my wife asked me how could I ride the same bike path day after day? I would run science experiments during the rides. Now she rides with me almost every day and that makes it interesting.

 

[Gionnirocket]

I rediscovered that once, doing battery mileage tests. It's the same amount of work for the the two batteries. This was back when my wife asked me how could I ride the same bike path day after day? I would run science experiments during the rides. Now she rides with me almost every day and that makes it interesting.

Too funny... I often find myself doing the same.
Lately I see if I can do the same 18 or 24 mile round trip and return with a smaller drop in no load voltage.
Though I think your latter pass time is much better.

@Thomas
Very good... we got you thinking. See, not so silly after all

But I think we've lost BCBeaver

 

[tomjasz]

See, not so silly after all

Still silly. I just don't get why we amateurs would even attempt these sorts of adventures. Over 5 years of support I've had more than a few fellas get creative and then claim warranty replacements for the controller they buggered. Another reason I never sell BMS boards. To easy for the uninformed to bugger. Once any modifications are made the 1-year warranty is a vapor!

 

[BCBeaver]

I have 2 11s5p battery packs that I got for free. They were new but the BMS in both had s*it the bed. That is the only reason I'm wondering about under volting a 48v motor (I have a Bbs02b on a bike that hasn't moved in a year so it's time change it up). I realize overvolting will let the smoke out of electronics not designed for more voltage but low voltage never lets out the smoke. Trying to get the same power with less voltage can let out the smoke if you run your current too high.

Including these packs I have about 250 matched Samsung cells so now I'm thinking I might build one big ass pack at 48V. I'd be building it to run a Tongsheng mid drive up front of a recumbent bike. With 2 front chainrings I could make it fly yet still be able to climb hills with a load on.

My goal is to be able to get 300km out of one charge. There are rail trails and logging roads through the BC southern interior between my house and Christina lake. It's a trip I drive fairly often but I'd like to be able to ride it in a day.

 

[BCBeaver]

Too funny... I often find myself doing the same.
Lately I see if I can do the same 18 or 24 mile round trip and return with a smaller drop in no load voltage.
Though I think your latter pass time is much better.

@Thomas
Very good... we got you thinking. See, not so silly after all

But I think we've lost BCBeaver

Didn't lose me, I've just been busy AF lately. All these people with free time is keeping the e bike store hopping. That combined with my electrical engineering gig and I haven't had time to much lately.