Makers like Shorai and Haiji say their relatively new development of vehicle starter batteries using lithium technology that's revolutionised the useability of tools like power drills, screwdrivers and torches have advantages including vastly reduced weight ( important on a bulky overweight steed like a 2-valve K-bike ) and for bike use, double the cranking amperage and triple the re-cycle rate of lead acid types. Plus the much reduced overall size makes for easier handling whilst installing, with more fumble-space for attaching the pos and neg cables.  Current motorcycle application lithiums cost around 200 bucks, similar to a dry battery like the Odyssey.

Anybody out there using one currently ? ( no pun intended ) 

ALAN in s.e. Spain, where winter draws on - temps might fall as low as 20 !

I have been watching these batteries, but at their price I am not ready to buy one for an experiment yet. Would be great if I could borrow one and test it on the bike and the microlight first.

Anybody out there using one currently ? ( no pun intended )

Watt are the downsides? Apart from the known fire risk that Boeing are keen to deny? I have had two Li phone batteries burst so am wary of them.

Most need a specialised charger for maintenance.

Al

Seems to work for this guy.
As for a specialised charger, the bike system does not have one and the claim is LiPo4 batteries do not lose their charge over time.

The only reason I might entertain the idea is if it is more reliable at the same price (if I was that concerned about the weight of a bike, I'd start by getting rid of the pillion footrests and chopping the seat in half). 

Or go on a diet...?