I could probably use that title for a number of things… however here I am of course talking about Voltage
Short story: Broken down $200 craigslisted GS450 becomes [after several months of of grunting, grinding, welding, searching, researching, spending, assembling, and spraypainting,] my pride and joy 72V battery powered Electric Death Machine!
For the technically interested, the drivetrian consists of a D&D Systems separately excited motor powered by a CAN programmable Sevcon controller and 72v, 35Ah of sealed lead acid. Charging is accomplished with 6 individual four stage 7amp constant current “smart” chargers, and a Kelly DC-DC converter is used to provide a 12v signal to the ‘standard’ motorcycle electronics. Regenerative braking is automatically activated with release of the throttle, and can be modulated with a second lever located on the left handlebar (think engine braking and clutch lever on an ICE bike).
The project was ‘finished’ back in April ’09, in time to be ridden to and featured in Santa Barbara’s Green Car Show, However after riding on and off for several months, the SLA batteries spouted their last electrons and are now sitting at an uncomfortable -5v.. It is well known that SLA batteries SUCK anyways (and actually ended up being my performance bottleneck), so I am saving up and hoping to swap in a Lithium pack sometime hopefully this year. Current lithium packs have greater energy density, are lighter, have better discharge characteristics and longer lifespans than sealed lead acid, only problem is they are (as of this writing) ~4x the price (a pack and BMS system for my motorcycle would run around $3k) … A LiFePO4 pack would mean significant gains in terms maximum range and acceleration.
I have most of the parts laying around for an embedded security system, which, initially will require fingerprint authentication to activate ignition (O.K. its not really an ignition, its a primary contactor…) , and eventually will also include GPS and GSM/GPRS communication so that the bike’s location can be queried via cell phone, or alerts can be sent in the event of invalid activation attempts. However I have found my desire to actually implement this diminished as, until I replace the batteries, the bike is unrideable anyways..
More pretty Pictures:
Also be sure to check out http://www.elmoto.net/ , probably the best electric motorcycle resource out there.