Thoughts on this donor bike, battery setup?

any thoughts on this donor bike? i will do 3X EV battery on top tube and then two on either side of top tube. and a mid motor mebe 3kW to 7.5? battery is 12"x7"x6". i think my legs (im short) will not hit the two batteries over the top tube. i dunno... found an example of it but not sure about his battery size.

No experience with them, but I wouldn't trust the strength of a a Chinese folding bike frame for anything more than casual pedaling. Not worth it to me to risk catastrophic frame failure going 30 mph, over a simple, but strong triangle frame. On the other hand, if you need a folder, then there may be designs that are stronger than others.

i need it to be able to stick two batteries below the top tube without hitting bottom tube (none in this case) and yes it will go faster than 30 mebe 50... ty for the safety reminder though. ill need to think on that.

Lot of better frames for ebike.

yeh but i need to fit 6kwH of batteries on there 3x 12by7by6...

Which means your frame needs to be even stronger than you think. Strapping too much battery weight to ordinary bikes seldom works well. Its a lot of cargo weight, and often calls for cargo bikes. Ordinary frames seldom stiff enough from side to side. Wobble develops that limits speed to very slow riding.

Better off to start with a decently stiff DH type mtb frame, then spread battery all over it. Some on a rear rack, some in the frame, and more on the handlebars. That's the only real solution if a cargo bike won't work.

Best way to carry a lot of battery is to get out the welder, and start modifying a steel bike. I built this one specifically to carry 40000 wh. For most rides, 2000 wh in the two frame bags was plenty, but I could pack more in the saddlebags when needed. So most rides carried all the weight in the center.

dogman dan said:

Which means your frame needs to be even stronger than you think. Strapping too much battery weight to ordinary bikes seldom works well. Its a lot of cargo weight, and often calls for cargo bikes. Ordinary frames seldom stiff enough from side to side. Wobble develops that limits speed to very slow riding.

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yeh, i agree. though in my defense, its 80-100lb in batteries and im only like 130-140lb. how about after getting all the batteries and motor in the final positions, i try to reinforce the frame with a DIY down tube? problem is I dont know how to weld or bend pipes or cut pipes. I mean I can cut pipes but dont have tools.

err on a side note, I want to use this bike as also exploring long long range ebike shop where I take good quality used EV batteries and put them into bikes and ebike kits for others to buy who dont want to wire BMS and do battery mounting framing etc. it be a niche market for folks with long commutes or who want to do cruising and not worry about battery life. Something like 2kwH-6kwH.

bakaneko ,

If you do not have a welder, or live in a house or have a shop where you can make/modify your own steel bike frame ...
Then just make your life easier by buying a e-bike specific frame.
I am not sure which one will work with a Big Block / 3000 kw mid -drive motor like what you have .
You will have to e-mail/call the seller of the frame to have them tell you if your motor would work on their frame. ( only buy from a vendor that you can call and talk to , as many people have had problems with internet sales with no after sales service )
I would use/buy a different frame than that folding frame you have .

I mean do you know if it will fit 3x EV batteries that are 12x6x7. I can see one on top but would the other two fit inside. I can modify it. I can learn to weld. Just wondering if there is a sizable or niche market for massive range ebikes (legal and "off road"). either way, I want to do this.

Research the Yuba Mundo Bike.

Yuba used to sell just the frame, perhaps they still do . Around $ 600 USD.
You could buy just the frame and use most of the parts off the folding bike you have.
Advantages for a frame like the Mundo, or like Dogman Dan's is plenty of space for large battery packs and long wheelbase for better stability at higher speeds .

Remember you'll get tired of a heavy heavy bike. It gets old. And I'm 240 lbs.