There is enough room for 24 A123 26650 cells in a 4S6P configuration, but not enough room for the wiring unless the battery box is lengthened 5mm or so. Probably overkill with 24 cells, but you'd never strain that battery. 720 amps for 10 seconds. That might start the bike.
I may do it.
Maviryk wants $150 for 8 cells, $225 for 12 cells, $300 for 16 cells. I expect he'd charge $375 for 24 cells, and I'm not going to pay that. The new green cells are $188 on eBay for 24 cells. I have some soft copper sheet to make strips from.
Realisticaly, 8 cells is adequate, 12 is plenty, and 16 is insurance. 16 cells on eBay are $140 and will fit in the battery box with room to spare. 15 cells wired 4S4P in a square or nested square pack would be easy to build and allow plenty of room for foam to absorb vibration.
Supposedly these cells don't need the balancing harness and electronics like lithium polymer. Anyone know for sure? I suppose it really doesn't matter since I can't find a balancer for these cells.
Got some more studying to do.