Hi! Occasional e-biker, occasional reader, first-time poster. My technical expertise is at the level of "I believe it runs on some form of electricity" and I know the difference between a watt and an amp, but past that point, as a bike tech I'm about capable of adjusting a derailleur. Barely. So please be merciful.
I have an old EV Global Motors SX 36v, the classic Iacocca bike, with SLA which still runs great and which I use for my daily 15-mile round trip commute. It works, barely, for that; I ride it in, charge it, ride it home, repeat. I usually arrive at work with a fluttering erg or two left in the tank but no more. The battery pack is older and undoubtedly at the end of its useful life. It needs to be replaced. My budget is very low.
I would like to convert the bike to LiPo. In fact, I have two 12v 8Ah LiPo battery packs and their charger from a different e-bike which I no longer have. I suspect that this would actually be cheaper than buying new SLAs, because my understanding is that I can keep the existing 500w motor (which still runs strong) and that all I actually need is a new controller, plus whatever mechanical modifications I need to jigger the new battery pack(s) into the old spaces. Looking at the frame, I can easily fit one of the LiPo packs into the oversized downtube on the bike, and swap out packs if I kill one during a ride.
1) Am I basically OK in my approach here, or am I wrong on some fundamental point?
2) What kind of controller do I need?
3) How hard is it to make the swap and rewire the innards?
4) How about the battery terminals? The SLA pack uses a different kind of connection to the bike than the LiPo packs have.
Thanks in advance for help and advice!