Battery Vehicle Society

Hey all..

was wondering how to decide which motor to use to replace an existing 249cc motor in a motocross bike?

the max power at the moment is 42hp but i've read that the electric motor doesn't need anywhere near that amount... which left me confused because they mass hasn't changed! it still has to move the same bike! why can people run cars etc on electric motors that have so much less power?

is there some sort of formula i can work out the power i need for my bike?

also i have a list of tech for my conversion, can anyone tell me if i'm missing something or have something in there for no reason? Cheers!!

Motor - obvious!
Batteries - lithium ion, local battery place almost fainted when i asked them for what i needed...
Cooling pump and module
DC/DC converter - wasn't sure about this - do i need it? am not keeping any electrics from the original bike - literally just the frame, forks, suspension, saddle, wheels etc...
Controller - been recomended the Brusa MD95 which looks ok...
Ignition key switch - obvious again
Dash - dials and guages
Main super fuse/fuse mounting box
Plugs and connectors
Circuitbreaker - can anyone recommend one?

thanks for any help!

If you get the opportunity, have a word with Trevor Lees at LMC he's got the motors and has been into motocross bikes a while now I believe he's the UK importer of another one now too

Unlikely to need a water cooler and how are you powering your instrumentation ?