What is the most efficient way to charge a battery with an engine?

[BioHazard]

Wow, that's a lot more efficient than I thought for belt drives. Thanks for the tips bob, you sound like somebody that would be fun to sit down and have a beer with. 

[mobile_bob]

a V drive can be pretty darned efficient but you must follow the engineering supplied by the manufacture.

lots of folks think they know better including the oems engineering depts.

usually it is a series of compromises, wherein if the oem can shave even a dime off a high sales volume end product
by going with a smaller pulley he will do so,  even if it means the lifespan of the drive is reduced.

reduce the lifespan by ~20% and save the oem a million dollars?  hmmm
is it any wonder why things don't last as they should?

bob g